[PATCH] JDK-8054565: FilterOutputStream.close may throw IOException if called twice and underlying flush or close fails

[Nathan Clement]

Hi,

My apologies - the page http://openjdk.java.net/contribute/ gave me the impression that I could send the diff as an attachment.  I've included it inline below.

Regards,

Nathan

diff --git a/src/share/classes/java/io/FilterOutputStream.java b/src/share/classes/java/io/FilterOutputStream.java
--- a/src/share/classes/java/io/FilterOutputStream.java
+++ b/src/share/classes/java/io/FilterOutputStream.java
@@ -47,6 +47,11 @@
      * The underlying output stream to be filtered.
      */
     protected OutputStream out;
+    
+    /**
+     * Whether this stream has already been closed or not
+     */
+    protected boolean closed = false;
 
     /**
      * Creates an output stream filter built on top of the specified
@@ -154,8 +159,11 @@
      */
     @SuppressWarnings("try")
     public void close() throws IOException {
-        try (OutputStream ostream = out) {
-            flush();
+        if (!closed) {
+            closed = true;
+            try (OutputStream ostream = out) {
+                flush();
+            }
         }
     }
 }
diff --git a/test/java/io/FilterOutputStream/CloseTwiceTest.java b/test/java/io/FilterOutputStream/CloseTwiceTest.java
new file mode 100644
--- /dev/null
+++ b/test/java/io/FilterOutputStream/CloseTwiceTest.java
@@ -0,0 +1,88 @@
+/*
+ * Copyright (c) 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
+ * 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package java.io.FilterOutputStream;
+
+import java.io.BufferedOutputStream;
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.lang.String;
+import java.util.zip.Deflater;
+import java.util.zip.DeflaterOutputStream;
+
+/**
+ * @test
+ * @bug 8054565
+ * @summary Test that closing a FilterOutputStream twice does not cause 
+ *    an exception when the underlying stream throws an exception when
+ *    close is called before flush.
+ */
+
+public class CloseTwiceTest
+{
+    /**
+     * This stream simulates a OracleBlobOutputStream which will throw
+     * an exception if flush is called after close.
+     */
+    static class MockBlobOutputStream extends ByteArrayOutputStream
+    {
+        private boolean closed;
+
+        @Override
+        public void flush() throws IOException
+        {
+            if (closed) {
+                throw new IOException("Stream closed");
+            }
+        }
+
+        @Override
+        public void close() throws IOException
+        {
+            closed = true;
+        }
+    }
+
+    public static void main( final String[] args ) throws Exception
+    {
+        try( InputStream bis = new ByteArrayInputStream( "Hello".getBytes() );
+             OutputStream outStream = new MockBlobOutputStream();
+             BufferedOutputStream bos = new BufferedOutputStream( outStream );
+             DeflaterOutputStream deflaterStream = new DeflaterOutputStream(
+                 bos, new Deflater( 3 ) ) )
+        {
+            int len = 0;
+            final byte[] buf = new byte[1024];
+            while ((len = bis.read(buf)) >= 0)
+            {
+                if ( len > 0 )
+                {
+                    deflaterStream.write(buf,0,len);
+                }
+            }
+        }
+    }
+}


> Date: Thu, 4 Dec 2014 09:40:24 -0500
> From: roger.riggs at oracle.com
> To: core-libs-dev at openjdk.java.net
> Subject: Re: [PATCH] JDK-8054565: FilterOutputStream.close may throw	IOException if called twice and underlying flush or close fails
> 
> Hi Nathan,
> 
> This list removes attachments.
> Can the diff's be inlined in the email?
> 
> Thanks, Roger
> 
> On 12/4/2014 1:18 AM, Nathan Clement wrote:
> > Hi,
> >
> > Here is my suggested fix for the FilterOuputStream issue in JDK-8054565.  I have been running this fix in my applications for several weeks (by adding it to the bootstrap classpath) and it solves my issue.  The fix creates a new member field to remember whether close has already been called on the stream, and if so, close() does nothing.
> >
> > Attached is the output from hg diff -g
> >
> > This is my first attempt at a patch for OpenJDK, so please let me know if I need to change anything.
> >
> > Thanks,
> >
> > Nathan
> >   		 	   		
>