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

Dan Xu dan.xu at oracle.com
Wed Aug 29 19:11:01 UTC 2012

On 08/29/2012 08:27 AM, Joe Darcy wrote:

Hello,

On 8/29/2012 1:48 AM, Rémi Forax wrote: On 08/29/2012 08:33 AM, Kurchi Subhra Hazra wrote:

Thanks for cleaning up those spaces Dan. The changes look fine. Sorry for the extra trouble!

- Kurchi On 8/28/12 10:22 PM, Dan Xu wrote: It is funny. :) I have searched all source codes under jdk and removed spaces for the similar cases.

Please review the new version of change at, http://cr.openjdk.java.net/~dxu/7193406/webrev.03/. Thanks for your comment! -Dan Hi Dan, In PreHashedMap, the code should be Map.Entry that = (Map.Entry)ob; so the @SuppressWarnings is not needed anymore. And in java.util.Arrays, asList() should not be annotated with @SuppressWarnings because it is already annotated with SafeVarargs, so the compiler should not report the varargs warning. I have CC to compiler-dev to be sure that this is a compiler error. cheers, Rémi I've spoken to Stuart about this last point. The @SafeVarargs covers uses of Array.asList and covers the declaration of the asList method itself. However, it does not cover calls to the constructor inside the asList method, a constructor which itself is not @SafeVarargs. Solutions include * @SuppressWarnings("varargs") on the asList method * @SuppressWarnings("varargs") on new temporary variable for that purpose (with possible class file size consequences) * @SafeVarargs on the ArrayList constructor Regards, -Joe The first change to the PreHashedMap is right, and I will update my fix.

For the second comment, as Joe mentioned, it is necessary. Otherwise, the compiler will give the following warnings.

../../../src/share/classes/java/util/Arrays.java:2837: warning:
[varargs] Varargs method could cause heap pollution from
non-reifiable varargs parameter a
         return new ArrayList<>(a);
                                ^
../../../src/share/classes/java/util/Arrays.java:2837: warning:
[varargs] Varargs method could cause heap pollution from
non-reifiable varargs parameter a
         return new ArrayList<>(a);

                            ^

The first and second options works fine. But if I follow the third option to add @SafeVarargs on the ArrayList constructor, I get the following error.

../../../src/share/classes/java/util/Arrays.java:2849: error:
Invalid SafeVarargs annotation. Method ArrayList(E[]) is not a
varargs method.
         ArrayList(E[] array) {
         ^
   where E is a type-variable:
     E extends Object declared in class ArrayList

So I tried further to change the constructor to a varargs method and add the @SafeVarargs annotation, but the compiler still gives me warnings like this,

../../../src/share/classes/java/util/Arrays.java:2837: warning:
[varargs] Varargs method could cause heap pollution from
non-reifiable varargs parameter a
         return new ArrayList<>(a);
                                ^
../../../src/share/classes/java/util/Arrays.java:2837: warning:
[varargs] Varargs method could cause heap pollution from
non-reifiable varargs parameter a
         return new ArrayList<>(a);
                                ^
../../../src/share/classes/java/util/Arrays.java:2852: warning:
[varargs] Varargs method could cause heap pollution from
non-reifiable varargs parameter array
             a = array;
                 ^
3 warnings

I think the current change is good for this one. Thanks for your comments.

-Dan

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