ISPN-3592 Avoid the DirectoryImplementor list() method to return null…

… elements in the returned array
infinispan · Oct 6, 2013 · 838a1ae · 838a1ae
1 parent cc6f8c9
commit 838a1ae
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Showing 2 changed files with 14 additions and 4 deletions.
diff --git a/lucene/lucene-v3/src/main/java/org/infinispan/lucene/InfinispanDirectory.java b/lucene/lucene-v3/src/main/java/org/infinispan/lucene/InfinispanDirectory.java
@@ -143,8 +143,13 @@ public InfinispanDirectory(Cache<?, ?> cache) {
     */
    public String[] list() {
       ensureOpen();
-      Set<String> filesList = fileOps.getFileList();
-      return filesList.toArray(new String[filesList.size()]);
+      Set<String> files = fileOps.getFileList();
+      //Careful! if you think you can optimize this array allocation, think again.
+      //The _files_ are a concurrent structure, its size could vary in parallel:
+      //the array population and dimensioning need to be performed atomically
+      //to avoid trailing null elements in the returned array.
+      String[] array = files.toArray(new String[0]);
+      return array;
    }
 
    /**

diff --git a/lucene/lucene-v3/src/main/java/org/infinispan/lucene/impl/DirectoryImplementor.java b/lucene/lucene-v3/src/main/java/org/infinispan/lucene/impl/DirectoryImplementor.java
@@ -51,8 +51,13 @@ public DirectoryImplementor(Cache<?, ?> metadataCache, Cache<?, ?> chunksCache,
      }
 
     String[] list() {
-       final Set<String> filesList = fileOps.getFileList();
-       return filesList.toArray(new String[filesList.size()]);
+       final Set<String> files = fileOps.getFileList();
+       //Careful! if you think you can optimize this array allocation, think again.
+       //The _files_ are a concurrent structure, its size could vary in parallel:
+       //the array population and dimensioning need to be performed atomically
+       //to avoid trailing null elements in the returned array.
+       final String[] array = files.toArray(new String[0]);
+       return array;
     }
 
     boolean fileExists(final String name) {