fix #124

pom.xml

@@ -603,7 +603,7 @@
     <dependency>
       <groupId>org.codelibs.solr</groupId>
       <artifactId>solrlib</artifactId>
-      <version>1.1.2</version>
+      <version>1.2.0-SNAPSHOT</version>
     </dependency>
     <dependency>
       <groupId>org.codelibs.sastruts</groupId>

src/main/java/jp/sf/fess/Constants.java

@@ -19,6 +19,7 @@ package jp.sf.fess;
 import java.util.regex.Pattern;
 
 import org.codelibs.core.CoreLibConstants;
+import org.codelibs.core.util.StringUtil;
 
 public class Constants extends CoreLibConstants {
     public static final int MAJOR_VERSION = 9;
@@ -35,10 +36,6 @@ public class Constants extends CoreLibConstants {
 
     public static final String WEB_API_VERSION = "5";
 
-    public static final String EMPTY_STRING = "";
-
-    public static final String[] EMPTY_STRINGS = new String[0];
-
     public static final String TRUE = "true";
 
     public static final String FALSE = "false";
@@ -188,7 +185,7 @@ public class Constants extends CoreLibConstants {
 
     public static final String SUPPORTED_SEARCH_NONE = "n";
 
-    public static final String DEFAULT_IGNORE_FAILURE_TYPE = "";
+    public static final String DEFAULT_IGNORE_FAILURE_TYPE = StringUtil.EMPTY;
 
     public static final String DEFAULT_FAILURE_COUNT = "-1";
 

src/main/java/jp/sf/fess/action/AppletAction.java

@@ -25,8 +25,8 @@ import jp.sf.fess.form.AppletForm;
 import jp.sf.fess.helper.SystemHelper;
 
 import org.apache.commons.lang.StringEscapeUtils;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.util.RequestUtil;
@@ -90,7 +90,7 @@ public class AppletAction {
 
         final String url = RequestUtil.getRequest().getHeader("REFERER");
         if (StringUtil.isBlank(url)) {
-            referrer = "";
+            referrer = StringUtil.EMPTY;
         } else {
             referrer = StringEscapeUtils.escapeJavaScript(url);
         }

src/main/java/jp/sf/fess/action/IndexAction.java

@@ -79,6 +79,7 @@ import org.apache.commons.io.IOUtils;
 import org.apache.commons.lang.StringEscapeUtils;
 import org.apache.commons.lang.StringUtils;
 import org.codelibs.core.util.DynamicProperties;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
 import org.codelibs.solr.lib.exception.SolrLibQueryException;
 import org.seasar.framework.beans.util.Beans;
@@ -86,7 +87,6 @@ import org.seasar.framework.container.annotation.tiger.Binding;
 import org.seasar.framework.container.annotation.tiger.BindingType;
 import org.seasar.framework.util.InputStreamUtil;
 import org.seasar.framework.util.OutputStreamUtil;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.taglib.S2Functions;
@@ -1107,8 +1107,7 @@ public class IndexAction {
         if (!labelTypeItems.isEmpty()
                 && !indexForm.fields.containsKey(LABEL_FIELD)) {
             final String defaultLabelValue = crawlerProperties.getProperty(
-                    Constants.DEFAULT_LABEL_VALUE_PROPERTY,
-                    Constants.EMPTY_STRING);
+                    Constants.DEFAULT_LABEL_VALUE_PROPERTY, StringUtil.EMPTY);
             if (StringUtil.isNotBlank(defaultLabelValue)) {
                 final String[] values = defaultLabelValue.split("\n");
                 if (values != null && values.length > 0) {

src/main/java/jp/sf/fess/action/LoginAction.java

@@ -39,7 +39,7 @@ import jp.sf.fess.util.ComponentUtil;
 import org.apache.struts.Globals;
 import org.codelibs.core.crypto.CachedCipher;
 import org.codelibs.sastruts.core.SSCConstants;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.util.RequestUtil;

src/main/java/jp/sf/fess/action/MobileAction.java

@@ -43,7 +43,7 @@ import org.apache.commons.lang.StringUtils;
 import org.codelibs.core.util.DynamicProperties;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.util.RequestUtil;

src/main/java/jp/sf/fess/action/admin/CrawlAction.java

@@ -30,6 +30,7 @@ import jp.sf.fess.form.admin.CrawlForm;
 import jp.sf.fess.helper.SystemHelper;
 
 import org.codelibs.core.util.DynamicProperties;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
 import org.seasar.struts.annotation.ActionForm;
@@ -71,7 +72,7 @@ public class CrawlAction implements Serializable {
         crawlForm.crawlingThreadCount = crawlerProperties.getProperty(
                 Constants.CRAWLING_THREAD_COUNT_PROPERTY, "5");
         crawlForm.mobileTranscoder = crawlerProperties.getProperty(
-                Constants.MOBILE_TRANSCODER_PROPERTY, Constants.EMPTY_STRING);
+                Constants.MOBILE_TRANSCODER_PROPERTY, StringUtil.EMPTY);
         crawlForm.searchLog = crawlerProperties.getProperty(
                 Constants.SEARCH_LOG_PROPERTY, Constants.TRUE);
         crawlForm.userInfo = crawlerProperties.getProperty(
@@ -83,7 +84,7 @@ public class CrawlAction implements Serializable {
         crawlForm.webApiJson = crawlerProperties.getProperty(
                 Constants.WEB_API_JSON_PROPERTY, Constants.TRUE);
         crawlForm.defaultLabelValue = crawlerProperties.getProperty(
-                Constants.DEFAULT_LABEL_VALUE_PROPERTY, "");
+                Constants.DEFAULT_LABEL_VALUE_PROPERTY, StringUtil.EMPTY);
         crawlForm.appendQueryParameter = crawlerProperties.getProperty(
                 Constants.APPEND_QUERY_PARAMETER_PROPERTY, Constants.FALSE);
         crawlForm.supportedSearch = crawlerProperties.getProperty(
@@ -112,7 +113,7 @@ public class CrawlAction implements Serializable {
                 Constants.PURGE_BY_BOTS_PROPERTY,
                 Constants.DEFAULT_PURGE_BY_BOTS);
         crawlForm.notificationTo = crawlerProperties.getProperty(
-                Constants.NOTIFICATION_TO_PROPERTY, Constants.EMPTY_STRING);
+                Constants.NOTIFICATION_TO_PROPERTY, StringUtil.EMPTY);
         if (redirect) {
             return "index?redirect=true";
         } else {
@@ -252,7 +253,7 @@ public class CrawlAction implements Serializable {
 
     public List<Map<String, String>> getMobileTranscoderItems() {
         final List<Map<String, String>> mobileTranscoderList = new ArrayList<Map<String, String>>();
-        mobileTranscoderList.add(createItem("-", Constants.EMPTY_STRING));
+        mobileTranscoderList.add(createItem("-", StringUtil.EMPTY));
         mobileTranscoderList.add(createItem(MessageResourcesUtil.getMessage(
                 RequestUtil.getRequest().getLocale(),
                 "labels.mobile_transcoder_google"),

src/main/java/jp/sf/fess/action/admin/DesignAction.java

@@ -36,10 +36,10 @@ import jp.sf.fess.helper.SystemHelper;
 import org.apache.commons.io.FileUtils;
 import org.apache.commons.io.IOUtils;
 import org.codelibs.core.util.DynamicProperties;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
 import org.seasar.framework.util.FileUtil;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.util.ResponseUtil;
@@ -211,7 +211,7 @@ public class DesignAction implements Serializable {
         final File jspFile = getJspFile(jspType);
 
         if (designForm.content == null) {
-            designForm.content = "";
+            designForm.content = StringUtil.EMPTY;
         }
 
         try {

src/main/java/jp/sf/fess/action/admin/DocumentAction.java

@@ -45,7 +45,7 @@ import org.codelibs.solr.lib.SolrGroupManager;
 import org.codelibs.solr.lib.SolrLibConstants;
 import org.codelibs.solr.lib.policy.QueryType;
 import org.codelibs.solr.lib.policy.impl.StatusPolicyImpl;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.taglib.S2Functions;

src/main/java/jp/sf/fess/action/admin/FavoriteLogAction.java

@@ -33,7 +33,7 @@ import org.apache.commons.io.IOUtils;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.util.RequestUtil;
 import org.seasar.struts.util.ResponseUtil;

src/main/java/jp/sf/fess/action/admin/FileAuthenticationAction.java

@@ -37,8 +37,8 @@ import jp.sf.fess.util.FessBeans;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;
 import org.seasar.struts.util.MessageResourcesUtil;
@@ -77,7 +77,7 @@ public class FileAuthenticationAction extends BsFileAuthenticationAction {
                 .commonColumnDateConverter().excludes("searchParams", "mode")
                 .execute();
         if ("-1".equals(fileAuthenticationForm.port)) {
-            fileAuthenticationForm.port = "";
+            fileAuthenticationForm.port = StringUtil.EMPTY;
         }
     }
 

src/main/java/jp/sf/fess/action/admin/LogAction.java

@@ -40,7 +40,7 @@ import jp.sf.fess.util.ComponentUtil;
 
 import org.apache.commons.codec.binary.Base64;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.util.ResponseUtil;

src/main/java/jp/sf/fess/action/admin/SearchListAction.java

@@ -40,7 +40,7 @@ import org.codelibs.solr.lib.SolrGroup;
 import org.codelibs.solr.lib.SolrGroupManager;
 import org.codelibs.solr.lib.policy.QueryType;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.taglib.S2Functions;

src/main/java/jp/sf/fess/action/admin/SearchLogAction.java

@@ -34,9 +34,9 @@ import jp.sf.fess.helper.SystemHelper;
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.util.RequestUtil;
 import org.seasar.struts.util.ResponseUtil;
@@ -60,7 +60,7 @@ public class SearchLogAction extends BsSearchLogAction {
     public String search() {
         final Map<String, String> searchParams = searchLogForm.searchParams;
         if (!searchParams.containsKey("startPage")) {
-            searchParams.put("startPage", Constants.EMPTY_STRING);
+            searchParams.put("startPage", StringUtil.EMPTY);
         }
         Beans.copy(searchParams, searchLogPager)
                 .excludes(CommonConstants.PAGER_CONVERSION_RULE).execute();

src/main/java/jp/sf/fess/action/admin/StatsAction.java

@@ -32,7 +32,7 @@ import jp.sf.fess.service.StatsService;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 

src/main/java/jp/sf/fess/action/admin/SystemAction.java

@@ -45,7 +45,7 @@ import org.codelibs.solr.lib.SolrGroupManager;
 import org.codelibs.solr.lib.SolrLibConstants;
 import org.codelibs.solr.lib.policy.QueryType;
 import org.codelibs.solr.lib.policy.impl.StatusPolicyImpl;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.util.RequestUtil;

src/main/java/jp/sf/fess/action/admin/SystemInfoAction.java

@@ -29,6 +29,7 @@ import jp.sf.fess.form.admin.SystemInfoForm;
 import jp.sf.fess.helper.SystemHelper;
 
 import org.codelibs.core.util.DynamicProperties;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 
@@ -118,9 +119,9 @@ public class SystemInfoAction implements Serializable {
             final Object value) {
         final Map<String, String> map = new HashMap<String, String>(2);
         map.put(Constants.ITEM_LABEL, label != null ? label.toString()
-                : Constants.EMPTY_STRING);
+                : StringUtil.EMPTY);
         map.put(Constants.ITEM_VALUE, value != null ? value.toString()
-                : Constants.EMPTY_STRING);
+                : StringUtil.EMPTY);
         return map;
     }
 }

src/main/java/jp/sf/fess/action/admin/WebAuthenticationAction.java

@@ -37,9 +37,9 @@ import jp.sf.fess.util.FessBeans;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;
 import org.seasar.struts.util.MessageResourcesUtil;
@@ -78,7 +78,7 @@ public class WebAuthenticationAction extends BsWebAuthenticationAction {
                 .commonColumnDateConverter().excludes("searchParams", "mode")
                 .execute();
         if ("-1".equals(webAuthenticationForm.port)) {
-            webAuthenticationForm.port = "";
+            webAuthenticationForm.port = StringUtil.EMPTY;
         }
     }
 

src/main/java/jp/sf/fess/action/admin/WizardAction.java

@@ -44,9 +44,9 @@ import jp.sf.fess.util.ComponentUtil;
 
 import org.apache.commons.lang.StringUtils;
 import org.codelibs.core.util.DynamicProperties;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.robot.util.CharUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
@@ -167,17 +167,13 @@ public class WizardAction implements Serializable {
                     wConfig.setDepth(Integer.parseInt(wizardForm.depth));
                 }
                 wConfig.setExcludedDocUrls(getDefaultString(
-                        "default.config.web.excludedDocUrls",
-                        Constants.EMPTY_STRING));
+                        "default.config.web.excludedDocUrls", StringUtil.EMPTY));
                 wConfig.setExcludedUrls(getDefaultString(
-                        "default.config.web.excludedUrls",
-                        Constants.EMPTY_STRING));
+                        "default.config.web.excludedUrls", StringUtil.EMPTY));
                 wConfig.setIncludedDocUrls(getDefaultString(
-                        "default.config.web.includedDocUrls",
-                        Constants.EMPTY_STRING));
+                        "default.config.web.includedDocUrls", StringUtil.EMPTY));
                 wConfig.setIncludedUrls(getDefaultString(
-                        "default.config.web.includedUrls",
-                        Constants.EMPTY_STRING));
+                        "default.config.web.includedUrls", StringUtil.EMPTY));
                 wConfig.setIntervalTime(getDefaultInteger(
                         "default.config.web.intervalTime",
                         Constants.DEFAULT_INTERVAL_TIME_FOR_WEB));
@@ -217,16 +213,14 @@ public class WizardAction implements Serializable {
                 }
                 fConfig.setExcludedDocPaths(getDefaultString(
                         "default.config.file.excludedDocPaths",
-                        Constants.EMPTY_STRING));
+                        StringUtil.EMPTY));
                 fConfig.setExcludedPaths(getDefaultString(
-                        "default.config.file.excludedPaths",
-                        Constants.EMPTY_STRING));
+                        "default.config.file.excludedPaths", StringUtil.EMPTY));
                 fConfig.setIncludedDocPaths(getDefaultString(
                         "default.config.file.includedDocPaths",
-                        Constants.EMPTY_STRING));
+                        StringUtil.EMPTY));
                 fConfig.setIncludedPaths(getDefaultString(
-                        "default.config.file.includedPaths",
-                        Constants.EMPTY_STRING));
+                        "default.config.file.includedPaths", StringUtil.EMPTY));
                 fConfig.setIntervalTime(getDefaultInteger(
                         "default.config.file.intervalTime",
                         Constants.DEFAULT_INTERVAL_TIME_FOR_FS));

src/main/java/jp/sf/fess/action/admin/dict/SynonymAction.java

@@ -23,7 +23,6 @@ import java.util.Map;
 
 import javax.annotation.Resource;
 
-import jp.sf.fess.Constants;
 import jp.sf.fess.crud.CommonConstants;
 import jp.sf.fess.crud.CrudMessageException;
 import jp.sf.fess.crud.util.SAStrutsUtil;
@@ -37,10 +36,10 @@ import jp.sf.fess.service.SynonymService;
 import org.apache.commons.lang3.StringUtils;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;
@@ -337,8 +336,8 @@ public class SynonymAction {
 
             }
         } else {
-            synonymItem = new SynonymItem(0, Constants.EMPTY_STRINGS,
-                    Constants.EMPTY_STRINGS);
+            synonymItem = new SynonymItem(0, StringUtil.EMPTY_STRINGS,
+                    StringUtil.EMPTY_STRINGS);
         }
 
         final String[] newInputs = splitLine(synonymForm.inputs);
@@ -351,7 +350,7 @@ public class SynonymAction {
 
     private String[] splitLine(final String value) {
         if (StringUtil.isBlank(value)) {
-            return Constants.EMPTY_STRINGS;
+            return StringUtil.EMPTY_STRINGS;
         }
         final String[] values = value.split("[\r\n]");
         final List<String> list = new ArrayList<String>(values.length);

src/main/java/jp/sf/fess/action/admin/dict/UserDictAction.java

@@ -22,7 +22,6 @@ import java.util.Map;
 
 import javax.annotation.Resource;
 
-import jp.sf.fess.Constants;
 import jp.sf.fess.crud.CommonConstants;
 import jp.sf.fess.crud.CrudMessageException;
 import jp.sf.fess.crud.util.SAStrutsUtil;
@@ -35,10 +34,10 @@ import jp.sf.fess.service.UserDictService;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.codelibs.sastruts.core.exception.SSCActionMessagesException;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;
@@ -337,9 +336,8 @@ public class UserDictAction {
 
             }
         } else {
-            userDictItem = new UserDictItem(0, Constants.EMPTY_STRING,
-                    Constants.EMPTY_STRING, Constants.EMPTY_STRING,
-                    Constants.EMPTY_STRING);
+            userDictItem = new UserDictItem(0, StringUtil.EMPTY,
+                    StringUtil.EMPTY, StringUtil.EMPTY, StringUtil.EMPTY);
         }
 
         userDictItem.setNewToken(userDictForm.token);

src/main/java/jp/sf/fess/annotation/CronExpression.java

@@ -21,6 +21,7 @@ import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.Arg;
 import org.seasar.struts.annotation.Msg;
 import org.seasar.struts.annotation.Validator;
@@ -41,13 +42,13 @@ public @interface CronExpression {
      * 
      * @return
      */
-    Arg arg0() default @Arg(key = "");
+    Arg arg0() default @Arg(key = StringUtil.EMPTY);
 
     /**
      * a target name for this validation
      * 
      * @return
      */
-    String target() default "";
+    String target() default StringUtil.EMPTY;
 
 }

src/main/java/jp/sf/fess/annotation/UriType.java

@@ -21,6 +21,7 @@ import java.lang.annotation.Retention;
 import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.Arg;
 import org.seasar.struts.annotation.Msg;
 import org.seasar.struts.annotation.Validator;
@@ -44,13 +45,13 @@ public @interface UriType {
      * 
      * @return
      */
-    Arg arg0() default @Arg(key = "");
+    Arg arg0() default @Arg(key = StringUtil.EMPTY);
 
     /**
      * a target name for this validation
      * 
      * @return
      */
-    String target() default "";
+    String target() default StringUtil.EMPTY;
 
 }

src/main/java/jp/sf/fess/api/json/JsonApiManager.java

@@ -46,7 +46,7 @@ import jp.sf.fess.util.WebApiUtil;
 
 import org.apache.commons.lang.StringEscapeUtils;
 import org.codelibs.core.CoreLibConstants;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.util.RequestUtil;
 import org.seasar.struts.util.ResponseUtil;
 import org.slf4j.Logger;
@@ -98,7 +98,7 @@ public class JsonApiManager extends BaseApiManager implements WebApiManager {
             processFavoritesRequest(request, response, chain);
             break;
         default:
-            writeJsonResponse(99, Constants.EMPTY_STRING, "Not found.");
+            writeJsonResponse(99, StringUtil.EMPTY, "Not found.");
             break;
         }
     }
@@ -106,7 +106,7 @@ public class JsonApiManager extends BaseApiManager implements WebApiManager {
     protected void processSearchRequest(final HttpServletRequest request,
             final HttpServletResponse response, final FilterChain chain) {
         int status = 0;
-        String errMsg = Constants.EMPTY_STRING;
+        String errMsg = StringUtil.EMPTY;
         String query = null;
         final StringBuilder buf = new StringBuilder(1000);
         request.setAttribute(Constants.SEARCH_LOG_ACCESS_TYPE,
@@ -302,7 +302,7 @@ public class JsonApiManager extends BaseApiManager implements WebApiManager {
     protected void processLabelRequest(final HttpServletRequest request,
             final HttpServletResponse response, final FilterChain chain) {
         int status = 0;
-        String errMsg = Constants.EMPTY_STRING;
+        String errMsg = StringUtil.EMPTY;
         final StringBuilder buf = new StringBuilder(255);
         try {
             final List<Map<String, String>> labelTypeItems = ComponentUtil
@@ -343,7 +343,7 @@ public class JsonApiManager extends BaseApiManager implements WebApiManager {
             final HttpServletResponse response, final FilterChain chain) {
 
         int status = 0;
-        String errMsg = Constants.EMPTY_STRING;
+        String errMsg = StringUtil.EMPTY;
         final StringBuilder buf = new StringBuilder(255);
         try {
             chain.doFilter(new WebApiRequest(request, SUGGEST_API),
@@ -427,7 +427,7 @@ public class JsonApiManager extends BaseApiManager implements WebApiManager {
             final HttpServletResponse response, final FilterChain chain) {
 
         int status = 0;
-        String errMsg = Constants.EMPTY_STRING;
+        String errMsg = StringUtil.EMPTY;
         final StringBuilder buf = new StringBuilder(255);
         try {
             chain.doFilter(new WebApiRequest(request, ANALYSIS_API),
@@ -517,7 +517,7 @@ public class JsonApiManager extends BaseApiManager implements WebApiManager {
             final HttpServletResponse response, final FilterChain chain) {
 
         int status = 0;
-        String errMsg = Constants.EMPTY_STRING;
+        String errMsg = StringUtil.EMPTY;
         final StringBuilder buf = new StringBuilder(255);
         try {
             chain.doFilter(new WebApiRequest(request, HOT_SEARCH_WORD_API),
@@ -656,7 +656,7 @@ public class JsonApiManager extends BaseApiManager implements WebApiManager {
     }
 
     protected String escapeCallbackName(final String callbackName) {
-        return callbackName.replaceAll("[^0-9a-zA-Z_\\$\\.]", "");
+        return callbackName.replaceAll("[^0-9a-zA-Z_\\$\\.]", StringUtil.EMPTY);
     }
 
     protected String escapeJson(final Object obj) {

src/main/java/jp/sf/fess/api/xml/XmlApiManager.java

@@ -45,7 +45,7 @@ import jp.sf.fess.util.WebApiUtil;
 
 import org.apache.commons.lang.StringEscapeUtils;
 import org.codelibs.core.CoreLibConstants;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.util.ResponseUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
@@ -86,7 +86,7 @@ public class XmlApiManager extends BaseApiManager implements WebApiManager {
             processAnalysisRequest(request, response, chain);
             break;
         default:
-            writeXmlResponse(-1, Constants.EMPTY_STRING, "Not found.");
+            writeXmlResponse(-1, StringUtil.EMPTY, "Not found.");
             break;
         }
 
@@ -95,7 +95,7 @@ public class XmlApiManager extends BaseApiManager implements WebApiManager {
     protected void processSearchRequest(final HttpServletRequest request,
             final HttpServletResponse response, final FilterChain chain) {
         int status = 0;
-        String errMsg = Constants.EMPTY_STRING;
+        String errMsg = StringUtil.EMPTY;
         final StringBuilder buf = new StringBuilder(1000);
         String query = null;
         request.setAttribute(Constants.SEARCH_LOG_ACCESS_TYPE,
@@ -255,7 +255,7 @@ public class XmlApiManager extends BaseApiManager implements WebApiManager {
     protected void processLabelRequest(final HttpServletRequest request,
             final HttpServletResponse response, final FilterChain chain) {
         int status = 0;
-        String errMsg = Constants.EMPTY_STRING;
+        String errMsg = StringUtil.EMPTY;
         final StringBuilder buf = new StringBuilder(255);
         try {
             final List<Map<String, String>> labelTypeItems = ComponentUtil
@@ -291,7 +291,7 @@ public class XmlApiManager extends BaseApiManager implements WebApiManager {
             final HttpServletResponse response, final FilterChain chain) {
 
         int status = 0;
-        String errMsg = Constants.EMPTY_STRING;
+        String errMsg = StringUtil.EMPTY;
         final StringBuilder buf = new StringBuilder(255);
         try {
             chain.doFilter(new WebApiRequest(request, SUGGEST_API),
@@ -371,7 +371,7 @@ public class XmlApiManager extends BaseApiManager implements WebApiManager {
             final HttpServletResponse response, final FilterChain chain) {
 
         int status = 0;
-        String errMsg = Constants.EMPTY_STRING;
+        String errMsg = StringUtil.EMPTY;
         final StringBuilder buf = new StringBuilder(255);
         try {
             chain.doFilter(new WebApiRequest(request, ANALYSIS_API),

src/main/java/jp/sf/fess/crud/action/admin/BsBrowserTypeAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsCrawlingSessionAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsDataCrawlingConfigAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsFailureUrlAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsFavoriteLogAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsFileAuthenticationAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsFileCrawlingConfigAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsJobLogAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsLabelTypeAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsOverlappingHostAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsPathMappingAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsRequestHeaderAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsRoleTypeAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsScheduledJobAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsSearchLogAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsUserInfoAction.java

@@ -36,7 +36,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsWebAuthenticationAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/crud/action/admin/BsWebCrawlingConfigAction.java

@@ -35,7 +35,7 @@ import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.sastruts.core.annotation.Token;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.ActionForm;
 import org.seasar.struts.annotation.Execute;
 import org.seasar.struts.exception.ActionMessagesException;

src/main/java/jp/sf/fess/db/exentity/DataCrawlingConfig.java

@@ -36,7 +36,7 @@ import org.apache.http.auth.UsernamePasswordCredentials;
 import org.apache.http.impl.auth.BasicScheme;
 import org.apache.http.impl.auth.DigestScheme;
 import org.apache.http.impl.auth.NTLMScheme;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.robot.client.S2RobotClientFactory;
 import org.seasar.robot.client.http.Authentication;
 import org.seasar.robot.client.http.HcHttpClient;
@@ -298,12 +298,13 @@ public class DataCrawlingConfig extends BsDataCrawlingConfig implements
                     final String domain = paramMap.get(S2ROBOT_WEB_AUTH + "."
                             + webAuthName + ".domain");
                     credentials = new NTCredentials(username,
-                            password == null ? "" : password,
-                            workstation == null ? "" : workstation,
-                            domain == null ? "" : domain);
+                            password == null ? StringUtil.EMPTY : password,
+                            workstation == null ? StringUtil.EMPTY
+                                    : workstation,
+                            domain == null ? StringUtil.EMPTY : domain);
                 } else {
                     credentials = new UsernamePasswordCredentials(username,
-                            password == null ? "" : password);
+                            password == null ? StringUtil.EMPTY : password);
                 }
 
                 basicAuthList.add(new AuthenticationImpl(authScope,
@@ -362,7 +363,8 @@ public class DataCrawlingConfig extends BsDataCrawlingConfig implements
                     }
 
                     final SmbAuthentication smbAuth = new SmbAuthentication();
-                    smbAuth.setDomain(domain == null ? "" : domain);
+                    smbAuth.setDomain(domain == null ? StringUtil.EMPTY
+                            : domain);
                     smbAuth.setServer(hostname);
                     if (StringUtil.isNotBlank(port)) {
                         try {
@@ -372,7 +374,8 @@ public class DataCrawlingConfig extends BsDataCrawlingConfig implements
                         }
                     }
                     smbAuth.setUsername(username);
-                    smbAuth.setPassword(password == null ? "" : password);
+                    smbAuth.setPassword(password == null ? StringUtil.EMPTY
+                            : password);
                     smbAuthList.add(smbAuth);
                 }
             }

src/main/java/jp/sf/fess/db/exentity/FailureUrl.java

@@ -22,6 +22,8 @@ import jp.sf.fess.Constants;
 import jp.sf.fess.db.bsentity.BsFailureUrl;
 import jp.sf.fess.util.ComponentUtil;
 
+import org.codelibs.core.util.StringUtil;
+
 /**
  * The entity of FAILURE_URL.
  * <p>
@@ -50,7 +52,7 @@ public class FailureUrl extends BsFailureUrl {
         if (crawlingConfig != null) {
             return crawlingConfig.getName();
         }
-        return Constants.EMPTY_STRING;
+        return StringUtil.EMPTY;
     }
 
     public String getFileConfigName() {
@@ -59,7 +61,7 @@ public class FailureUrl extends BsFailureUrl {
         if (crawlingConfig != null) {
             return crawlingConfig.getName();
         }
-        return Constants.EMPTY_STRING;
+        return StringUtil.EMPTY;
     }
 
     public String getDataConfigName() {
@@ -68,6 +70,6 @@ public class FailureUrl extends BsFailureUrl {
         if (crawlingConfig != null) {
             return crawlingConfig.getName();
         }
-        return Constants.EMPTY_STRING;
+        return StringUtil.EMPTY;
     }
 }

src/main/java/jp/sf/fess/db/exentity/FileCrawlingConfig.java

@@ -31,8 +31,8 @@ import jp.sf.fess.service.FileAuthenticationService;
 import jp.sf.fess.util.ComponentUtil;
 import jp.sf.fess.util.ParameterUtil;
 
+import org.codelibs.core.util.StringUtil;
 import org.seasar.framework.container.SingletonS2Container;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.robot.client.S2RobotClientFactory;
 import org.seasar.robot.client.smb.SmbAuthentication;
 import org.seasar.robot.client.smb.SmbClient;
@@ -254,7 +254,7 @@ public class FileCrawlingConfig extends BsFileCrawlingConfig implements
                 final Map<String, String> map = ParameterUtil.parse(fileAuth
                         .getParameters());
                 final String domain = map.get("domain");
-                smbAuth.setDomain(domain == null ? "" : domain);
+                smbAuth.setDomain(domain == null ? StringUtil.EMPTY : domain);
                 smbAuth.setServer(fileAuth.getHostname());
                 smbAuth.setPort(fileAuth.getPort());
                 smbAuth.setUsername(fileAuth.getUsername());

src/main/java/jp/sf/fess/db/exentity/LabelType.java

@@ -21,7 +21,7 @@ import java.util.List;
 
 import jp.sf.fess.db.bsentity.BsLabelType;
 
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 /**
  * The entity of LABEL_TYPE.

src/main/java/jp/sf/fess/db/exentity/SearchLog.java

@@ -21,7 +21,7 @@ import java.text.SimpleDateFormat;
 import jp.sf.fess.Constants;
 import jp.sf.fess.db.bsentity.BsSearchLog;
 
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 /**
  * The entity of SEARCH_LOG.

src/main/java/jp/sf/fess/db/exentity/WebAuthentication.java

@@ -30,7 +30,7 @@ import org.apache.http.auth.UsernamePasswordCredentials;
 import org.apache.http.impl.auth.BasicScheme;
 import org.apache.http.impl.auth.DigestScheme;
 import org.apache.http.impl.auth.NTLMScheme;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.robot.RobotSystemException;
 import org.seasar.robot.client.http.Authentication;
 import org.seasar.robot.client.http.impl.AuthenticationImpl;
@@ -101,12 +101,12 @@ public class WebAuthentication extends BsWebAuthentication {
             final String workstation = parameterMap.get("workstation");
             final String domain = parameterMap.get("domain");
             return new NTCredentials(getUsername(), getPassword(),
-                    workstation == null ? "" : workstation, domain == null ? ""
-                            : domain);
+                    workstation == null ? StringUtil.EMPTY : workstation,
+                    domain == null ? StringUtil.EMPTY : domain);
         }
 
         return new UsernamePasswordCredentials(getUsername(),
-                getPassword() == null ? "" : getPassword());
+                getPassword() == null ? StringUtil.EMPTY : getPassword());
     }
 
 }

src/main/java/jp/sf/fess/db/exentity/WebCrawlingConfig.java

@@ -31,7 +31,7 @@ import jp.sf.fess.service.WebAuthenticationService;
 import jp.sf.fess.util.ParameterUtil;
 
 import org.seasar.framework.container.SingletonS2Container;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.robot.client.S2RobotClientFactory;
 import org.seasar.robot.client.http.Authentication;
 import org.seasar.robot.client.http.HcHttpClient;

src/main/java/jp/sf/fess/dict/DictionaryManager.java

@@ -28,7 +28,7 @@ import org.seasar.extension.timer.TimeoutTarget;
 import org.seasar.extension.timer.TimeoutTask;
 import org.seasar.framework.container.annotation.tiger.DestroyMethod;
 import org.seasar.framework.container.annotation.tiger.InitMethod;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

src/main/java/jp/sf/fess/dict/synonym/SynonymFile.java

@@ -35,6 +35,7 @@ import jp.sf.fess.dict.DictionaryFile;
 
 import org.apache.commons.io.FileUtils;
 import org.apache.commons.io.IOUtils;
+import org.codelibs.core.util.StringUtil;
 
 public class SynonymFile extends DictionaryFile<SynonymItem> {
     private static final String SYNONYM = "synonym";
@@ -131,8 +132,8 @@ public class SynonymFile extends DictionaryFile<SynonymItem> {
     @Override
     public synchronized void delete(final SynonymItem item) {
         final SynonymItem synonymItem = item;
-        synonymItem.setNewInputs(new String[0]);
-        synonymItem.setNewOutputs(new String[0]);
+        synonymItem.setNewInputs(StringUtil.EMPTY_STRINGS);
+        synonymItem.setNewOutputs(StringUtil.EMPTY_STRINGS);
         SynonymUpdater updater = null;
         try {
             updater = new SynonymUpdater(file, synonymItem);

src/main/java/jp/sf/fess/dict/userdict/UserDictFile.java

@@ -36,6 +36,7 @@ import jp.sf.fess.dict.DictionaryFile;
 import org.apache.commons.io.FileUtils;
 import org.apache.commons.io.IOUtils;
 import org.apache.lucene.analysis.ja.util.CSVUtil;
+import org.codelibs.core.util.StringUtil;
 
 public class UserDictFile extends DictionaryFile<UserDictItem> {
     private static final String USERDICT = "userDict";
@@ -133,7 +134,7 @@ public class UserDictFile extends DictionaryFile<UserDictItem> {
     @Override
     public synchronized void delete(final UserDictItem item) {
         final UserDictItem userDictItem = item;
-        userDictItem.setNewToken(Constants.EMPTY_STRING);
+        userDictItem.setNewToken(StringUtil.EMPTY);
         UserDictUpdater updater = null;
         try {
             updater = new UserDictUpdater(file, userDictItem);
@@ -155,7 +156,7 @@ public class UserDictFile extends DictionaryFile<UserDictItem> {
             String line = null;
             while ((line = reader.readLine()) != null) {
                 // Remove comments
-                line = line.replaceAll("#.*$", "");
+                line = line.replaceAll("#.*$", StringUtil.EMPTY);
 
                 // Skip empty lines or comment lines
                 if (line.trim().length() == 0) {

src/main/java/jp/sf/fess/ds/impl/AbstractDataStoreImpl.java

@@ -31,8 +31,8 @@ import jp.sf.fess.helper.SystemHelper;
 import jp.sf.fess.taglib.FessFunctions;
 import jp.sf.fess.util.ComponentUtil;
 
+import org.codelibs.core.util.StringUtil;
 import org.seasar.framework.util.OgnlUtil;
-import org.seasar.framework.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -124,7 +124,7 @@ public abstract class AbstractDataStoreImpl implements DataStore {
     protected Object convertValue(final String template,
             final Map<String, String> paramMap) {
         if (StringUtil.isEmpty(template)) {
-            return Constants.EMPTY_STRING;
+            return StringUtil.EMPTY;
         }
 
         try {

src/main/java/jp/sf/fess/ds/impl/CsvDataStoreImpl.java

@@ -38,8 +38,8 @@ import jp.sf.orangesignal.csv.CsvConfig;
 import jp.sf.orangesignal.csv.CsvReader;
 
 import org.apache.commons.io.IOUtils;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.framework.container.SingletonS2Container;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.robot.RobotCrawlAccessException;
 import org.seasar.robot.RobotMultipleCrawlAccessException;
 import org.slf4j.Logger;
@@ -214,7 +214,7 @@ public class CsvDataStoreImpl extends AbstractDataStoreImpl {
                     String key = null;
                     String value = list.get(i);
                     if (value == null) {
-                        value = Constants.EMPTY_STRING;
+                        value = StringUtil.EMPTY;
                     }
                     if (headerList != null && headerList.size() > i) {
                         key = headerList.get(i);

src/main/java/jp/sf/fess/ds/impl/DatabaseDataStoreImpl.java

@@ -32,7 +32,7 @@ import jp.sf.fess.db.exentity.DataCrawlingConfig;
 import jp.sf.fess.ds.DataStoreException;
 import jp.sf.fess.ds.IndexUpdateCallback;
 
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

src/main/java/jp/sf/fess/entity/GeoInfo.java

@@ -16,7 +16,7 @@
 
 package jp.sf.fess.entity;
 
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.Mask;
 import org.seasar.struts.annotation.Maxbytelength;
 

src/main/java/jp/sf/fess/entity/SearchQuery.java

@@ -21,7 +21,7 @@ import java.util.List;
 
 import jp.sf.fess.Constants;
 
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 public class SearchQuery {
     private String query;

src/main/java/jp/sf/fess/exec/Crawler.java

@@ -53,6 +53,7 @@ import jp.sf.fess.util.ResourceUtil;
 
 import org.codelibs.core.CoreLibConstants;
 import org.codelibs.core.util.DynamicProperties;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.solr.lib.SolrGroup;
 import org.codelibs.solr.lib.SolrGroupManager;
 import org.codelibs.solr.lib.policy.QueryType;
@@ -72,7 +73,6 @@ import org.seasar.framework.container.servlet.SingletonS2ContainerInitializer;
 import org.seasar.framework.mock.servlet.MockHttpServletRequestImpl;
 import org.seasar.framework.mock.servlet.MockHttpServletResponseImpl;
 import org.seasar.framework.mock.servlet.MockServletContextImpl;
-import org.seasar.framework.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -362,7 +362,7 @@ public class Crawler implements Serializable {
             }
 
             final FileTemplateLoader loader = new FileTemplateLoader(new File(
-                    ResourceUtil.getMailTemplatePath("")));
+                    ResourceUtil.getMailTemplatePath(StringUtil.EMPTY)));
             final Handlebars handlebars = new Handlebars(loader);
 
             try {

src/main/java/jp/sf/fess/form/admin/StatsForm.java

@@ -22,7 +22,7 @@ import java.util.Map;
 
 import jp.sf.fess.Constants;
 
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.annotation.IntegerType;
 
 public class StatsForm implements Serializable {

src/main/java/jp/sf/fess/form/admin/WebCrawlingConfigForm.java

@@ -24,7 +24,7 @@ import jp.sf.fess.Constants;
 import jp.sf.fess.crud.form.admin.BsWebCrawlingConfigForm;
 import jp.sf.fess.util.ComponentUtil;
 
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 public class WebCrawlingConfigForm extends BsWebCrawlingConfigForm implements
         Serializable {

src/main/java/jp/sf/fess/helper/CrawlingSessionHelper.java

@@ -39,7 +39,7 @@ import org.apache.solr.client.solrj.response.FacetField;
 import org.apache.solr.client.solrj.response.QueryResponse;
 import org.codelibs.solr.lib.SolrGroup;
 import org.seasar.framework.container.SingletonS2Container;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

src/main/java/jp/sf/fess/helper/FileTypeHelper.java

@@ -3,7 +3,7 @@ package jp.sf.fess.helper;
 import java.util.HashMap;
 import java.util.Map;
 
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 public class FileTypeHelper {
     protected String fieldName = "filetype_s";

src/main/java/jp/sf/fess/helper/HotSearchWordHelper.java

@@ -34,7 +34,7 @@ import jp.sf.fess.db.exbhv.pmbean.HotSearchWordPmb;
 
 import org.seasar.dbflute.jdbc.CursorHandler;
 import org.seasar.framework.container.annotation.tiger.InitMethod;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 public class HotSearchWordHelper {
 

src/main/java/jp/sf/fess/helper/LabelTypeHelper.java

@@ -34,7 +34,7 @@ import jp.sf.fess.service.LabelTypeService;
 
 import org.seasar.framework.container.SingletonS2Container;
 import org.seasar.framework.container.annotation.tiger.InitMethod;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

src/main/java/jp/sf/fess/helper/OpenSearchHelper.java

@@ -28,7 +28,7 @@ import jp.sf.fess.FessSystemException;
 import org.apache.commons.io.IOUtils;
 import org.seasar.framework.container.annotation.tiger.InitMethod;
 import org.seasar.framework.util.FileUtil;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.util.ServletContextUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

src/main/java/jp/sf/fess/helper/SystemHelper.java

@@ -43,13 +43,13 @@ import jp.sf.fess.util.ResourceUtil;
 
 import org.apache.commons.lang.LocaleUtils;
 import org.apache.commons.lang.StringUtils;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.solr.lib.SolrGroup;
 import org.codelibs.solr.lib.policy.QueryType;
 import org.codelibs.solr.lib.policy.StatusPolicy;
 import org.seasar.framework.container.SingletonS2Container;
 import org.seasar.framework.container.annotation.tiger.InitMethod;
 import org.seasar.framework.util.FileUtil;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.robot.util.CharUtil;
 import org.seasar.struts.util.MessageResourcesUtil;
 import org.seasar.struts.util.RequestUtil;
@@ -470,7 +470,7 @@ public class SystemHelper implements Serializable {
     }
 
     public String generateDocId(final Map<String, Object> map) {
-        return UUID.randomUUID().toString().replace("-", "");
+        return UUID.randomUUID().toString().replace("-", StringUtil.EMPTY);
     }
 
     public String abbreviateLongText(final String str) {

src/main/java/jp/sf/fess/helper/ViewHelper.java

@@ -39,7 +39,7 @@ import jp.sf.fess.helper.UserAgentHelper.UserAgentType;
 
 import org.apache.commons.lang.StringUtils;
 import org.codelibs.core.util.DynamicProperties;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.framework.util.URLUtil;
 import org.seasar.robot.util.CharUtil;
 import org.seasar.struts.taglib.S2Functions;
@@ -121,7 +121,7 @@ public class ViewHelper implements Serializable {
 
     public String getContentDescription(final Map<String, Object> document) {
         final HttpServletRequest request = RequestUtil.getRequest();
-        final String[] queries = request == null ? new String[0]
+        final String[] queries = request == null ? StringUtil.EMPTY_STRINGS
                 : (String[]) request.getAttribute(Constants.HIGHLIGHT_QUERIES);
         int size;
         if (browserTypeHelper.isMobile()) {
@@ -138,11 +138,12 @@ public class ViewHelper implements Serializable {
             }
         }
 
-        return "";
+        return StringUtil.EMPTY;
     }
 
     protected String removeEmTag(final String str) {
-        return str.replaceAll("<em>", "").replaceAll("</em>", "");
+        return str.replaceAll("<em>", StringUtil.EMPTY).replaceAll("</em>",
+                StringUtil.EMPTY);
     }
 
     protected String highlight(final String content, final String[] queries) {
@@ -281,8 +282,7 @@ public class ViewHelper implements Serializable {
 
         if (browserTypeHelper.isMobile()) {
             final String mobileTrasncoder = crawlerProperties.getProperty(
-                    Constants.MOBILE_TRANSCODER_PROPERTY,
-                    Constants.EMPTY_STRING);
+                    Constants.MOBILE_TRANSCODER_PROPERTY, StringUtil.EMPTY);
             if (Constants.GOOGLE_MOBILE_TRANSCODER.equals(mobileTrasncoder)) {
                 return getGoogleMobileTranscoderLink(appendQueryParameter(
                         document, url));

src/main/java/jp/sf/fess/helper/WebFsIndexHelper.java

@@ -35,9 +35,9 @@ import jp.sf.fess.solr.IndexUpdater;
 import jp.sf.fess.util.ComponentUtil;
 
 import org.codelibs.core.util.DynamicProperties;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.solr.lib.SolrGroup;
 import org.seasar.framework.container.SingletonS2Container;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.robot.S2Robot;
 import org.seasar.robot.S2RobotContext;
 import org.seasar.robot.service.DataService;
@@ -183,9 +183,9 @@ public class WebFsIndexHelper implements Serializable {
                     .setDelayMillisForWaitingNewUrl(intervalTime);
 
             final String includedUrlsStr = webCrawlingConfig.getIncludedUrls() != null ? webCrawlingConfig
-                    .getIncludedUrls() : "";
+                    .getIncludedUrls() : StringUtil.EMPTY;
             final String excludedUrlsStr = webCrawlingConfig.getExcludedUrls() != null ? webCrawlingConfig
-                    .getExcludedUrls() : "";
+                    .getExcludedUrls() : StringUtil.EMPTY;
 
             // num of threads
             final S2RobotContext robotContext = s2Robot.getRobotContext();
@@ -299,10 +299,10 @@ public class WebFsIndexHelper implements Serializable {
 
             final String includedPathsStr = fileCrawlingConfig
                     .getIncludedPaths() != null ? fileCrawlingConfig
-                    .getIncludedPaths() : "";
+                    .getIncludedPaths() : StringUtil.EMPTY;
             final String excludedPathsStr = fileCrawlingConfig
                     .getExcludedPaths() != null ? fileCrawlingConfig
-                    .getExcludedPaths() : "";
+                    .getExcludedPaths() : StringUtil.EMPTY;
 
             // num of threads
             final S2RobotContext robotContext = s2Robot.getRobotContext();

src/main/java/jp/sf/fess/helper/impl/CookieUserInfoHelperImpl.java

@@ -30,7 +30,7 @@ import jp.sf.fess.Constants;
 import jp.sf.fess.helper.SearchLogHelper;
 import jp.sf.fess.helper.UserInfoHelper;
 
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.robot.util.LruHashMap;
 import org.seasar.struts.util.RequestUtil;
 import org.seasar.struts.util.ResponseUtil;
@@ -80,7 +80,7 @@ public class CookieUserInfoHelperImpl implements UserInfoHelper {
     }
 
     protected String getId() {
-        return UUID.randomUUID().toString().replace("-", "");
+        return UUID.randomUUID().toString().replace("-", StringUtil.EMPTY);
     }
 
     protected void updateUserSessionId(final String userCode) {
@@ -137,7 +137,7 @@ public class CookieUserInfoHelperImpl implements UserInfoHelper {
                 return queryId;
             }
         }
-        return Constants.EMPTY_STRING;
+        return StringUtil.EMPTY;
     }
 
     @Override
@@ -150,7 +150,7 @@ public class CookieUserInfoHelperImpl implements UserInfoHelper {
                 return urls;
             }
         }
-        return new String[0];
+        return StringUtil.EMPTY_STRINGS;
     }
 
     private Map<String, String[]> getResultDocIdsCache(final HttpSession session) {

src/main/java/jp/sf/fess/helper/impl/H2DatabaseHelperImpl.java

@@ -19,6 +19,7 @@ package jp.sf.fess.helper.impl;
 import jp.sf.fess.helper.DatabaseHelper;
 import jp.sf.fess.util.ResourceUtil;
 
+import org.codelibs.core.util.StringUtil;
 import org.h2.tools.DeleteDbFiles;
 import org.h2.tools.RunScript;
 import org.slf4j.Logger;
@@ -30,11 +31,11 @@ public class H2DatabaseHelperImpl implements DatabaseHelper {
 
     public String databaseName = "robot";
 
-    public String databasePath = ResourceUtil.getDbPath("");
+    public String databasePath = ResourceUtil.getDbPath(StringUtil.EMPTY);
 
     public String user = "sa";
 
-    public String password = "";
+    public String password = StringUtil.EMPTY;
 
     public String sqlFilePath = ResourceUtil.getClassesPath("sql/robot.ddl");
 

src/main/java/jp/sf/fess/helper/impl/QueryHelperImpl.java

@@ -45,10 +45,9 @@ import jp.sf.fess.util.QueryUtil;
 import jp.sf.fess.util.SearchParamMap;
 
 import org.apache.commons.lang.StringUtils;
-import org.codelibs.core.CoreLibConstants;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.framework.container.annotation.tiger.Binding;
 import org.seasar.framework.container.annotation.tiger.BindingType;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.struts.util.RequestUtil;
 
 public class QueryHelperImpl implements QueryHelper, Serializable {
@@ -175,7 +174,7 @@ public class QueryHelperImpl implements QueryHelper, Serializable {
 
         final SearchQuery searchQuery = buildQuery(q);
         if (!searchQuery.queryExists()) {
-            return searchQuery.query(Constants.EMPTY_STRING);
+            return searchQuery.query(StringUtil.EMPTY);
         }
 
         if (browserTypeHelper == null && roleQueryHelper == null
@@ -251,7 +250,7 @@ public class QueryHelperImpl implements QueryHelper, Serializable {
                 fieldLogMap);
         String solrQuery;
         if (q == null || "()".equals(q)) {
-            solrQuery = Constants.EMPTY_STRING;
+            solrQuery = StringUtil.EMPTY;
             // } else if (q.startsWith("(") && q.endsWith(")")) {
             // solrQuery = q.substring(1, q.length() - 1);
         } else {
@@ -447,7 +446,7 @@ public class QueryHelperImpl implements QueryHelper, Serializable {
             searchQueryBuf.append(queryBuf.toString());
             operator = _AND_;
         } else {
-            operator = Constants.EMPTY_STRING;
+            operator = StringUtil.EMPTY;
         }
         if (!notOperatorList.isEmpty()) {
             final String q = searchQueryBuf.toString();
@@ -773,7 +772,7 @@ public class QueryHelperImpl implements QueryHelper, Serializable {
         final String q = buildFacetQueryInternal(query);
         String solrQuery;
         if (q == null || "()".equals(q)) {
-            solrQuery = Constants.EMPTY_STRING;
+            solrQuery = StringUtil.EMPTY;
         } else {
             solrQuery = unbracketQuery(q);
         }
@@ -784,7 +783,7 @@ public class QueryHelperImpl implements QueryHelper, Serializable {
         final List<QueryPart> queryPartList = splitQuery(query, null, null,
                 null);
         if (queryPartList.isEmpty()) {
-            return "";
+            return StringUtil.EMPTY;
         }
 
         final StringBuilder queryBuf = new StringBuilder(255);
@@ -870,7 +869,7 @@ public class QueryHelperImpl implements QueryHelper, Serializable {
             searchQueryBuf.append(queryBuf.toString());
             operator = _AND_;
         } else {
-            operator = Constants.EMPTY_STRING;
+            operator = StringUtil.EMPTY;
         }
         if (!notOperatorList.isEmpty()) {
             final String q = searchQueryBuf.toString();
@@ -967,7 +966,7 @@ public class QueryHelperImpl implements QueryHelper, Serializable {
     @Override
     public String buildOptionQuery(final SearchParamMap optionMap) {
         if (optionMap == null) {
-            return CoreLibConstants.EMPTY_STRING;
+            return StringUtil.EMPTY;
         }
 
         final StringBuilder buf = new StringBuilder();
@@ -1047,7 +1046,7 @@ public class QueryHelperImpl implements QueryHelper, Serializable {
             for (final String nq : nqs) {
                 if (StringUtil.isNotBlank(nq)) {
                     buf.append(' ');
-                    String split = CoreLibConstants.EMPTY_STRING;
+                    String split = StringUtil.EMPTY;
                     final List<QueryPart> partList = splitQuery(nq, null, null,
                             null);
                     for (final QueryPart part : partList) {
@@ -1438,7 +1437,7 @@ public class QueryHelperImpl implements QueryHelper, Serializable {
                     if (StringUtil.isNotBlank(param)) {
                         newValues[i] = param;
                     } else {
-                        newValues[i] = CoreLibConstants.EMPTY_STRING;
+                        newValues[i] = StringUtil.EMPTY;
                     }
                 } else {
                     newValues[i] = value;

src/main/java/jp/sf/fess/helper/impl/RoleQueryHelperImpl.java

@@ -34,7 +34,7 @@ import jp.sf.fess.helper.SystemHelper;
 
 import org.codelibs.core.crypto.CachedCipher;
 import org.codelibs.sastruts.core.SSCConstants;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.util.RequestUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

src/main/java/jp/sf/fess/helper/impl/SearchLogHelperImpl.java

@@ -40,8 +40,8 @@ import jp.sf.fess.service.UserInfoService;
 import jp.sf.fess.util.ComponentUtil;
 import jp.sf.fess.util.FessBeans;
 
+import org.codelibs.core.util.StringUtil;
 import org.seasar.framework.container.SingletonS2Container;
-import org.seasar.framework.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -73,10 +73,10 @@ public class SearchLogHelperImpl extends SearchLogHelper {
     protected void processSearchLogQueue(final Queue<SearchLog> queue) {
         final List<SearchLog> searchLogList = new ArrayList<SearchLog>();
         final String value = crawlerProperties.getProperty(
-                Constants.PURGE_BY_BOTS_PROPERTY, Constants.EMPTY_STRING);
+                Constants.PURGE_BY_BOTS_PROPERTY, StringUtil.EMPTY);
         String[] botNames;
         if (StringUtil.isBlank(value)) {
-            botNames = new String[0];
+            botNames = StringUtil.EMPTY_STRINGS;
         } else {
             botNames = value.split(",");
         }

src/main/java/jp/sf/fess/helper/impl/TomcatManagementHelperImpl.java

@@ -35,7 +35,7 @@ import org.apache.http.auth.UsernamePasswordCredentials;
 import org.apache.http.client.methods.HttpGet;
 import org.apache.http.impl.client.DefaultHttpClient;
 import org.seasar.framework.util.InputStreamUtil;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

src/main/java/jp/sf/fess/job/CrawlJob.java

@@ -37,7 +37,7 @@ import jp.sf.fess.util.InputStreamThread;
 import org.apache.commons.lang.StringUtils;
 import org.apache.commons.lang.SystemUtils;
 import org.seasar.framework.container.SingletonS2Container;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

src/main/java/jp/sf/fess/job/JobScheduler.java

@@ -43,7 +43,7 @@ import org.seasar.dbflute.cbean.EntityRowHandler;
 import org.seasar.framework.container.SingletonS2Container;
 import org.seasar.framework.container.annotation.tiger.DestroyMethod;
 import org.seasar.framework.container.annotation.tiger.InitMethod;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

src/main/java/jp/sf/fess/pager/StatsPager.java

@@ -24,7 +24,7 @@ import java.util.List;
 
 import jp.sf.fess.Constants;
 
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 import com.ibm.icu.text.SimpleDateFormat;
 

src/main/java/jp/sf/fess/screenshot/ScreenShotManager.java

@@ -37,7 +37,7 @@ import jp.sf.fess.util.ComponentUtil;
 
 import org.apache.commons.io.FileUtils;
 import org.seasar.framework.container.annotation.tiger.InitMethod;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.robot.util.LruHashMap;
 import org.seasar.struts.util.RequestUtil;
 import org.slf4j.Logger;

src/main/java/jp/sf/fess/service/ClickLogService.java

@@ -27,7 +27,6 @@ import java.util.List;
 
 import javax.annotation.Resource;
 
-import jp.sf.fess.Constants;
 import jp.sf.fess.db.cbean.ClickLogCB;
 import jp.sf.fess.db.cbean.SearchLogCB;
 import jp.sf.fess.db.exbhv.ClickLogBhv;
@@ -41,6 +40,7 @@ import jp.sf.orangesignal.csv.CsvWriter;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.core.CoreLibConstants;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.dbflute.cbean.EntityRowHandler;
 
 import com.ibm.icu.text.SimpleDateFormat;
@@ -129,7 +129,7 @@ public class ClickLogService implements Serializable {
                 private void addToList(final List<String> list,
                         final Object value) {
                     if (value == null) {
-                        list.add(Constants.EMPTY_STRING);
+                        list.add(StringUtil.EMPTY);
                     } else if (value instanceof Timestamp) {
                         list.add(sdf.format((Date) value));
                     } else {

src/main/java/jp/sf/fess/service/CrawlingSessionService.java

@@ -29,7 +29,6 @@ import java.util.Set;
 
 import javax.annotation.Resource;
 
-import jp.sf.fess.Constants;
 import jp.sf.fess.FessSystemException;
 import jp.sf.fess.crud.service.BsCrawlingSessionService;
 import jp.sf.fess.db.cbean.CrawlingSessionCB;
@@ -45,11 +44,11 @@ import jp.sf.orangesignal.csv.CsvWriter;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.core.CoreLibConstants;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.dbflute.bhv.DeleteOption;
 import org.seasar.dbflute.cbean.EntityRowHandler;
 import org.seasar.dbflute.cbean.ListResultBean;
 import org.seasar.dbflute.cbean.coption.LikeSearchOption;
-import org.seasar.framework.util.StringUtil;
 
 import com.ibm.icu.text.SimpleDateFormat;
 
@@ -263,7 +262,7 @@ public class CrawlingSessionService extends BsCrawlingSessionService implements
                         private void addToList(final List<String> list,
                                 final Object value) {
                             if (value == null) {
-                                list.add(Constants.EMPTY_STRING);
+                                list.add(StringUtil.EMPTY);
                             } else if (value instanceof Timestamp) {
                                 list.add(sdf.format((Date) value));
                             } else {

src/main/java/jp/sf/fess/service/DatabaseService.java

@@ -115,7 +115,7 @@ import jp.sf.fess.util.ComponentUtil;
 import org.codelibs.core.util.DynamicProperties;
 import org.seasar.dbflute.bhv.DeleteOption;
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

src/main/java/jp/sf/fess/service/FailureUrlService.java

@@ -43,7 +43,7 @@ import org.seasar.dbflute.bhv.DeleteOption;
 import org.seasar.dbflute.cbean.ListResultBean;
 import org.seasar.dbflute.cbean.coption.LikeSearchOption;
 import org.seasar.framework.container.SingletonS2Container;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 public class FailureUrlService extends BsFailureUrlService implements
         Serializable {

src/main/java/jp/sf/fess/service/FavoriteLogService.java

@@ -29,7 +29,6 @@ import java.util.Map;
 
 import javax.annotation.Resource;
 
-import jp.sf.fess.Constants;
 import jp.sf.fess.crud.service.BsFavoriteLogService;
 import jp.sf.fess.db.cbean.FavoriteLogCB;
 import jp.sf.fess.db.cbean.UserInfoCB;
@@ -43,10 +42,10 @@ import jp.sf.orangesignal.csv.CsvWriter;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.core.CoreLibConstants;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.dbflute.bhv.DeleteOption;
 import org.seasar.dbflute.cbean.EntityRowHandler;
 import org.seasar.dbflute.cbean.ListResultBean;
-import org.seasar.framework.util.StringUtil;
 
 import com.ibm.icu.text.SimpleDateFormat;
 
@@ -249,7 +248,7 @@ public class FavoriteLogService extends BsFavoriteLogService implements
                                     .selectEntity(cb);
                             String userCode;
                             if (userInfo == null) {
-                                userCode = Constants.EMPTY_STRING;
+                                userCode = StringUtil.EMPTY;
                             } else {
                                 userCode = userInfo.getCode();
                             }
@@ -269,7 +268,7 @@ public class FavoriteLogService extends BsFavoriteLogService implements
                         private void addToList(final List<String> list,
                                 final Object value) {
                             if (value == null) {
-                                list.add(Constants.EMPTY_STRING);
+                                list.add(StringUtil.EMPTY);
                             } else if (value instanceof Timestamp) {
                                 list.add(sdf.format((Date) value));
                             } else {

src/main/java/jp/sf/fess/service/SearchLogService.java

@@ -48,12 +48,12 @@ import net.arnx.jsonic.JSON;
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
 import org.codelibs.core.CoreLibConstants;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.dbflute.bhv.DeleteOption;
 import org.seasar.dbflute.cbean.EntityRowHandler;
 import org.seasar.dbflute.cbean.ListResultBean;
 import org.seasar.dbflute.cbean.coption.LikeSearchOption;
 import org.seasar.framework.container.SingletonS2Container;
-import org.seasar.framework.util.StringUtil;
 
 import com.ibm.icu.text.SimpleDateFormat;
 
@@ -261,8 +261,8 @@ public class SearchLogService extends BsSearchLogService implements
                     final ListResultBean<SearchFieldLog> fieldLogList = SingletonS2Container
                             .getComponent(SearchFieldLogBhv.class).selectList(
                                     cb);
-                    String query = Constants.EMPTY_STRING;
-                    String solrQuery = Constants.EMPTY_STRING;
+                    String query = StringUtil.EMPTY;
+                    String solrQuery = StringUtil.EMPTY;
                     final List<Map<String, String>> jsonObjList = new ArrayList<Map<String, String>>(
                             fieldLogList.size());
                     for (final SearchFieldLog fieldLog : fieldLogList) {
@@ -308,7 +308,7 @@ public class SearchLogService extends BsSearchLogService implements
                 private void addToList(final List<String> list,
                         final Object value) {
                     if (value == null) {
-                        list.add(Constants.EMPTY_STRING);
+                        list.add(StringUtil.EMPTY);
                     } else if (value instanceof Timestamp) {
                         list.add(sdf.format((Date) value));
                     } else {

src/main/java/jp/sf/fess/service/SearchService.java

@@ -52,7 +52,7 @@ import org.apache.solr.common.util.NamedList;
 import org.codelibs.solr.lib.SolrGroup;
 import org.codelibs.solr.lib.SolrGroupManager;
 import org.codelibs.solr.lib.policy.QueryType;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 public class SearchService implements Serializable {
 

src/main/java/jp/sf/fess/service/SynonymService.java

@@ -31,7 +31,7 @@ import jp.sf.fess.dict.synonym.SynonymItem;
 import jp.sf.fess.pager.SynonymPager;
 
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 public class SynonymService {
     @Resource

src/main/java/jp/sf/fess/service/UserDictService.java

@@ -31,7 +31,7 @@ import jp.sf.fess.dict.userdict.UserDictItem;
 import jp.sf.fess.pager.UserDictPager;
 
 import org.seasar.framework.beans.util.Beans;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 public class UserDictService {
     @Resource

src/main/java/jp/sf/fess/service/UserInfoService.java

@@ -34,7 +34,7 @@ import jp.sf.fess.pager.UserInfoPager;
 
 import org.seasar.dbflute.bhv.DeleteOption;
 import org.seasar.dbflute.bhv.UpdateOption;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 public class UserInfoService extends BsUserInfoService implements Serializable {
 

src/main/java/jp/sf/fess/solr/IndexUpdater.java

@@ -43,7 +43,7 @@ import org.seasar.dbflute.cbean.ListResultBean;
 import org.seasar.framework.container.SingletonS2Container;
 import org.seasar.framework.container.annotation.tiger.Binding;
 import org.seasar.framework.container.annotation.tiger.BindingType;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.robot.S2Robot;
 import org.seasar.robot.db.cbean.AccessResultCB;
 import org.seasar.robot.db.exbhv.AccessResultBhv;

src/main/java/jp/sf/fess/solr/policy/FessStatusPolicy.java

@@ -28,9 +28,9 @@ import jp.sf.fess.util.ComponentUtil;
 import jp.sf.fess.util.ResourceUtil;
 
 import org.codelibs.core.util.DynamicProperties;
+import org.codelibs.core.util.StringUtil;
 import org.codelibs.solr.lib.policy.QueryType;
 import org.codelibs.solr.lib.policy.impl.StatusPolicyImpl;
-import org.seasar.framework.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 
@@ -178,7 +178,7 @@ public class FessStatusPolicy extends StatusPolicyImpl {
             }
 
             final FileTemplateLoader loader = new FileTemplateLoader(new File(
-                    ResourceUtil.getMailTemplatePath("")));
+                    ResourceUtil.getMailTemplatePath(StringUtil.EMPTY)));
             final Handlebars handlebars = new Handlebars(loader);
 
             try {

src/main/java/jp/sf/fess/transformer/AbstractFessFileTransformer.java

@@ -47,9 +47,9 @@ import org.apache.commons.lang.StringUtils;
 import org.apache.tika.metadata.HttpHeaders;
 import org.apache.tika.metadata.TikaMetadataKeys;
 import org.codelibs.core.util.DynamicProperties;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.framework.container.SingletonS2Container;
 import org.seasar.framework.util.SerializeUtil;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.robot.RobotCrawlAccessException;
 import org.seasar.robot.RobotSystemException;
 import org.seasar.robot.client.smb.SmbClient;
@@ -226,7 +226,7 @@ public abstract class AbstractFessFileTransformer extends
         if (StringUtil.isNotBlank(body)) {
             putResultDataBody(dataMap, "content", body);
         } else {
-            putResultDataBody(dataMap, "content", "");
+            putResultDataBody(dataMap, "content", StringUtil.EMPTY);
         }
         final String cache = normalizeContent(content);
         if (enableCache) {
@@ -264,7 +264,7 @@ public abstract class AbstractFessFileTransformer extends
         // created
         putResultDataBody(dataMap, "created", "NOW");
         // TODO anchor
-        putResultDataBody(dataMap, "anchor", "");
+        putResultDataBody(dataMap, "anchor", StringUtil.EMPTY);
         // mimetype
         putResultDataBody(dataMap, "mimetype", mimeType);
         if (fileTypeHelper != null) {
@@ -365,7 +365,7 @@ public abstract class AbstractFessFileTransformer extends
             return null;
         }
 
-        name = name.replaceAll("/+$", "");
+        name = name.replaceAll("/+$", StringUtil.EMPTY);
         final int idx = name.lastIndexOf('/');
         if (idx >= 0) {
             name = name.substring(idx + 1);
@@ -435,7 +435,7 @@ public abstract class AbstractFessFileTransformer extends
     @Override
     protected String getHost(final String url) {
         if (StringUtil.isBlank(url)) {
-            return ""; // empty
+            return StringUtil.EMPTY; // empty
         }
 
         if (url.startsWith("file:////")) {
@@ -458,7 +458,7 @@ public abstract class AbstractFessFileTransformer extends
     @Override
     protected String getSite(final String url, final String encoding) {
         if (StringUtil.isBlank(url)) {
-            return ""; // empty
+            return StringUtil.EMPTY; // empty
         }
 
         if (url.startsWith("file:////")) {

src/main/java/jp/sf/fess/transformer/AbstractFessXpathTransformer.java

@@ -18,10 +18,8 @@ package jp.sf.fess.transformer;
 
 import java.net.URLDecoder;
 
-import jp.sf.fess.Constants;
-
 import org.apache.commons.lang.StringUtils;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.robot.transformer.impl.XpathTransformer;
 
 public abstract class AbstractFessXpathTransformer extends XpathTransformer {
@@ -35,7 +33,7 @@ public abstract class AbstractFessXpathTransformer extends XpathTransformer {
 
     protected String getHost(final String u) {
         if (StringUtil.isBlank(u)) {
-            return Constants.EMPTY_STRING; // empty
+            return StringUtil.EMPTY; // empty
         }
 
         String url = u;
@@ -60,7 +58,7 @@ public abstract class AbstractFessXpathTransformer extends XpathTransformer {
 
     protected String getSite(final String u, final String encoding) {
         if (StringUtil.isBlank(u)) {
-            return Constants.EMPTY_STRING; // empty
+            return StringUtil.EMPTY; // empty
         }
 
         String url = u;
@@ -102,7 +100,7 @@ public abstract class AbstractFessXpathTransformer extends XpathTransformer {
 
     protected String normalizeContent(final String content) {
         if (content == null) {
-            return Constants.EMPTY_STRING; // empty
+            return StringUtil.EMPTY; // empty
         }
         return content.replaceAll("\\s+", " ");
     }

src/main/java/jp/sf/fess/transformer/FessXpathTransformer.java

@@ -52,10 +52,10 @@ import jp.sf.fess.util.ComponentUtil;
 import org.apache.commons.io.IOUtils;
 import org.apache.commons.lang.StringUtils;
 import org.apache.xpath.objects.XObject;
+import org.codelibs.core.util.StringUtil;
 import org.cyberneko.html.parsers.DOMParser;
 import org.seasar.framework.util.OgnlUtil;
 import org.seasar.framework.util.SerializeUtil;
-import org.seasar.framework.util.StringUtil;
 import org.seasar.robot.RobotCrawlAccessException;
 import org.seasar.robot.RobotSystemException;
 import org.seasar.robot.client.fs.ChildUrlsException;
@@ -358,7 +358,7 @@ public class FessXpathTransformer extends AbstractFessXpathTransformer {
     protected String convertValue(final String template,
             final Map<String, Object> paramMap) {
         if (StringUtil.isEmpty(template)) {
-            return Constants.EMPTY_STRING;
+            return StringUtil.EMPTY;
         }
 
         try {
@@ -398,7 +398,7 @@ public class FessXpathTransformer extends AbstractFessXpathTransformer {
 
     String removeCommentTag(final String content) {
         if (content == null) {
-            return "";
+            return StringUtil.EMPTY;
         }
         String value = content;
         int pos = value.indexOf("<!--");

src/main/java/jp/sf/fess/util/ParameterUtil.java

@@ -19,10 +19,9 @@ package jp.sf.fess.util;
 import java.util.HashMap;
 import java.util.Map;
 
-import jp.sf.fess.Constants;
 import jp.sf.fess.FessSystemException;
 
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 
 public class ParameterUtil {
     protected ParameterUtil() {
@@ -45,10 +44,10 @@ public class ParameterUtil {
                                     .substring(pos + 1).trim());
                         } else {
                             paramMap.put(line.substring(0, pos).trim(),
-                                    Constants.EMPTY_STRING);
+                                    StringUtil.EMPTY);
                         }
                     } else {
-                        paramMap.put(line.trim(), Constants.EMPTY_STRING);
+                        paramMap.put(line.trim(), StringUtil.EMPTY);
                     }
                 }
             }

src/main/java/jp/sf/fess/util/QueryResponseList.java

@@ -33,7 +33,7 @@ import org.apache.solr.client.solrj.response.QueryResponse;
 import org.apache.solr.common.SolrDocument;
 import org.apache.solr.common.SolrDocumentList;
 import org.apache.solr.common.util.SimpleOrderedMap;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 

src/main/java/jp/sf/fess/util/ResourceUtil.java

@@ -24,7 +24,7 @@ import java.util.regex.Pattern;
 import javax.servlet.ServletContext;
 
 import org.seasar.framework.container.SingletonS2Container;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.util.ServletContextUtil;
 
 public class ResourceUtil {

src/main/java/jp/sf/fess/util/SearchParamMap.java

@@ -18,6 +18,8 @@ package jp.sf.fess.util;
 
 import java.util.HashMap;
 
+import org.codelibs.core.util.StringUtil;
+
 public class SearchParamMap extends HashMap<String, String[]> {
 
     private static final long serialVersionUID = 1L;
@@ -27,7 +29,7 @@ public class SearchParamMap extends HashMap<String, String[]> {
     @Override
     public String[] get(final Object key) {
         if (CLASS_NAME.equals(key)) {
-            return new String[0];
+            return StringUtil.EMPTY_STRINGS;
         }
         return super.get(key);
     }

src/main/java/jp/sf/fess/validator/CronExpressionChecks.java

@@ -23,7 +23,7 @@ import org.apache.commons.validator.Validator;
 import org.apache.commons.validator.ValidatorAction;
 import org.apache.struts.action.ActionMessages;
 import org.quartz.CronExpression;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.validator.S2FieldChecks;
 
 public class CronExpressionChecks extends S2FieldChecks {

src/main/java/jp/sf/fess/validator/UriTypeChecks.java

@@ -24,7 +24,7 @@ import org.apache.commons.validator.Field;
 import org.apache.commons.validator.Validator;
 import org.apache.commons.validator.ValidatorAction;
 import org.apache.struts.action.ActionMessages;
-import org.seasar.framework.util.StringUtil;
+import org.codelibs.core.util.StringUtil;
 import org.seasar.struts.validator.S2FieldChecks;
 
 public class UriTypeChecks extends S2FieldChecks {