support openjdk8/11

.travis.yml

@@ -5,11 +5,7 @@ language: java
 matrix:
   include:
     - jdk: openjdk8
-    - jdk: openjdk9
-      before_install:
-        - rm "${JAVA_HOME}/lib/security/cacerts"
-        - ln -s /etc/ssl/certs/java/cacerts "${JAVA_HOME}/lib/security/cacerts"
-    - jdk: openjdk10
+    - jdk: openjdk11
       before_install:
         - rm "${JAVA_HOME}/lib/security/cacerts"
         - ln -s /etc/ssl/certs/java/cacerts "${JAVA_HOME}/lib/security/cacerts"

src/main/java/org/codelibs/fess/indexer/IndexUpdater.java

@@ -106,7 +106,6 @@ public class IndexUpdater extends Thread {
         // nothing
     }
 
-    @Override
     @PreDestroy
     public void destroy() {
         if (!finishCrawling) {