Review Request: 7193406 - Clean-up JDK Build Warnings in java.util, java.io

[Dan Xu]

Please review the fix of CR 7193406 at 
http://cr.openjdk.java.net/~dxu/7193406/webrev/.

It cleans up warnings in the following java files.
   src/share/classes/java/io/FilePermission.java
   src/share/classes/java/util/ArrayDeque.java
   src/share/classes/java/util/Arrays.java
   src/share/classes/java/util/Collections.java
   src/share/classes/java/util/HashMap.java
   src/share/classes/java/util/JumboEnumSet.java
   src/share/classes/java/util/PriorityQueue.java
   src/share/classes/java/util/PropertyResourceBundle.java
   src/share/classes/java/util/jar/JarVerifier.java
   src/share/classes/java/util/jar/Pack200.java
   src/share/classes/sun/util/PreHashedMap.java



And it enables fatal warning flag in the following make file.

   make/java/jar/Makefile


In FilePermission.java file, I make one change to its method signature,

   public Enumeration elements()  ==> public Enumeration<Permission>
   elements()


I am not sure whether it will cause an issue of backward compatibility. 
Please advise. Thanks!

- Dan