--- a/langtools/src/share/classes/com/sun/tools/javac/file/ZipFileIndexArchive.java	Mon Jan 10 14:57:59 2011 -0800
+++ b/langtools/src/share/classes/com/sun/tools/javac/file/ZipFileIndexArchive.java	Mon Jan 10 15:08:31 2011 -0800
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2005, 2009, Oracle and/or its affiliates. All rights reserved.
+ * Copyright (c) 2005, 2011, Oracle and/or its affiliates. All rights reserved.
  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
  *
  * This code is free software; you can redistribute it and/or modify it
@@ -42,6 +42,7 @@
 import com.sun.tools.javac.file.JavacFileManager.Archive;
 import com.sun.tools.javac.file.RelativePath.RelativeDirectory;
 import com.sun.tools.javac.file.RelativePath.RelativeFile;
+import com.sun.tools.javac.util.Assert;
 import com.sun.tools.javac.util.List;
 
 /**
@@ -146,7 +147,7 @@
         @Override
         public InputStream openInputStream() throws IOException {
             if (inputStream == null) {
-                assert entry != null; // see constructor
+                Assert.checkNonNull(entry); // see constructor
                 inputStream = new ByteArrayInputStream(zfIndex.read(entry));
             }
             return inputStream;