--- /dev/null	Mon May 24 04:14:34 2010
+++ new/test/java/util/zip/GZIP/GZIPInputStreamRead.java	Mon May 24 04:14:32 2010
@@ -0,0 +1,100 @@
+/*
+ * Copyright 2010 Sun Microsystems, Inc.  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
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ */
+
+/* @test
+ * @bug 4691425
+ * @summary Test the read and write of GZIPInput/OutputStream, including
+ *          concatenated .gz inputstream
+ */
+
+import java.io.*;
+import java.util.*;
+import java.util.zip.*;
+
+public class GZIPInputStreamRead {
+    public static void main(String[] args) throws Throwable {
+        Random rnd = new Random();
+        for (int i = 1; i < 100; i++) {
+            int members = rnd.nextInt(10) + 1;
+
+            ByteArrayOutputStream srcBAOS = new ByteArrayOutputStream();
+            ByteArrayOutputStream dstBAOS = new ByteArrayOutputStream();
+            for (int j = 0; j < members; j++) {
+                byte[] src = new byte[rnd.nextInt(8192) + 1];
+                rnd.nextBytes(src);
+                srcBAOS.write(src);
+   
+                GZIPOutputStream gzos = new GZIPOutputStream(dstBAOS);
+                gzos.write(src);
+                gzos.close();
+	    }                
+            byte[] srcBytes = srcBAOS.toByteArray();
+            byte[] dstBytes = dstBAOS.toByteArray();
+            // try different size of buffer to read the
+            // GZIPInputStream
+            /* just for fun when running manually
+            for (int j = 1; j < 10; j++) {
+                test(srcBytes, dstBytes, j);
+            }
+            */
+            for (int j = 0; j < 10; j++) {
+                int readBufSZ = rnd.nextInt(2048) + 1;
+                test(srcBytes,
+                     dstBytes,
+                     readBufSZ,
+                     512);    // the defualt buffer size
+                test(srcBytes,
+                     dstBytes,
+                     readBufSZ,
+                     rnd.nextInt(4096) + 1);
+            }
+        }
+    }
+
+    private static void test(byte[] src, byte[] dst,
+                             int readBufSize, int gzisBufSize)
+        throws Throwable
+    {
+        GZIPInputStream gzis = new GZIPInputStream(
+                                   new ByteArrayInputStream(dst),
+                                   gzisBufSize);
+        byte[] result = new byte[src.length + 10];
+        byte[] buf = new byte[readBufSize];
+        int n = 0;
+        int off = 0;
+
+        while ((n = gzis.read(buf, 0, buf.length)) != -1) {
+            System.arraycopy(buf, 0, result, off, n);
+            off += n;
+            // no range check, if overflow, let it fail
+        }
+        if (off != src.length || gzis.available() != 0 ||
+            !Arrays.equals(src, Arrays.copyOf(result, off))) {
+            throw new RuntimeException(
+                "GZIPInputStream reading failed! " +
+                ", src.len=" + src.length +
+                ", read=" + off);
+        }
+        gzis.close();
+    }
+}