fix #20

pom.xml

@@ -452,7 +452,7 @@
     <dependency>
       <groupId>commons-codec</groupId>
       <artifactId>commons-codec</artifactId>
-      <version>1.6</version>
+      <version>1.9</version>
     </dependency>
     <dependency>
       <groupId>commons-collections</groupId>
@@ -483,7 +483,7 @@
     <dependency>
       <groupId>commons-io</groupId>
       <artifactId>commons-io</artifactId>
-      <version>2.2</version>
+      <version>2.4</version>
     </dependency>
     <dependency>
       <groupId>commons-lang</groupId>
@@ -785,7 +785,7 @@
     <dependency>
       <groupId>org.apache.pdfbox</groupId>
       <artifactId>pdfbox</artifactId>
-      <version>1.8.2</version>
+      <version>1.8.3</version>
     </dependency>
     <dependency>
       <groupId>org.apache.poi</groupId>