1 files changed, 0 insertions, 128 deletions
diff --git a/qpid/java/common/src/main/java/org/apache/qpid/util/concurrent/BooleanLatch.java b/qpid/java/common/src/main/java/org/apache/qpid/util/concurrent/BooleanLatch.java
deleted file mode 100644
index 0e4a07594f..0000000000
--- a/qpid/java/common/src/main/java/org/apache/qpid/util/concurrent/BooleanLatch.java
+++ /dev/null
@@ -1,128 +0,0 @@
-package org.apache.qpid.util.concurrent;
-/*
- * 
- * Licensed to the Apache Software Foundation (ASF) under one
- * or more contributor license agreements.  See the NOTICE file
- * distributed with this work for additional information
- * regarding copyright ownership.  The ASF licenses this file
- * to you under the Apache License, Version 2.0 (the
- * "License"); you may not use this file except in compliance
- * with the License.  You may obtain a copy of the License at
- * 
- *   http://www.apache.org/licenses/LICENSE-2.0
- * 
- * Unless required by applicable law or agreed to in writing,
- * software distributed under the License is distributed on an
- * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
- * KIND, either express or implied.  See the License for the
- * specific language governing permissions and limitations
- * under the License.
- * 
- */
-
-
-import java.util.concurrent.locks.AbstractQueuedSynchronizer;
-
-/**
- * A BooleanLatch is like a set of traffic lights, where threads can wait at a red light until another thread gives
- * the green light. When threads arrive at the latch it is initially red. They queue up until the green signal is
- * given, at which point they can all acquire the latch in shared mode and continue to run concurrently. Once the latch
- * is signalled it cannot be reset to red again.
- *
- * <p/> The latch uses a {@link java.util.concurrent.locks.AbstractQueuedSynchronizer} to implement its synchronization.
- * This has two internal states, 0 which means that the latch is blocked, and 1 which means that the latch is open.
- *
- * <p/><table id="crc"><caption>CRC Card</caption>
- * <tr><th> Responsibilities <th> Collaborations
- * <tr><td> Block threads until a go signal is given.
- * </table>
- *
- * @todo Might be better to use a countdown latch to count down from 1. Its await method can throw interrupted
- *       exception which makes the possibility of interruption more explicit, and provides a reminder to recheck the
- *       latch condition before continuing.
- */
-public class BooleanLatch
-{
-    /** Holds the synchronizer that provides the thread queueing synchronization. */
-    private final Sync sync = new Sync();
-
-    /**
-     * Tests whether or not the latch has been signalled, that is to say that, the light is green.
-     *
-     * <p/>This method is non-blocking.
-     *
-     * @return <tt>true</tt> if the latch may be acquired; the light is green.
-     */
-    public boolean isSignalled()
-    {
-        return sync.isSignalled();
-    }
-
-    /**
-     * Waits on the latch until the signal is given and the light is green. If the light is already green then the
-     * latch will be acquired and the thread will not have to wait.
-     *
-     * <p/>This method will block until the go signal is given or the thread is otherwise interrupted. Before carrying
-     * out any processing threads that return from this method should confirm that the go signal has really been given
-     * on this latch by calling the {@link #isSignalled()} method.
-     */
-    public void await()
-    {
-        sync.acquireShared(1);
-    }
-
-    /**
-     * Releases any threads currently waiting on the latch. This flips the light to green allowing any threads that
-     * were waiting for this condition to now run.
-     *
-     * <p/>This method is non-blocking.
-     */
-    public void signal()
-    {
-        sync.releaseShared(1);
-    }
-
-    /**
-     * Implements a thread queued synchronizer. The internal state 0 means that the queue is blocked and the internl
-     * state 1 means that the queue is released and that all waiting threads can acquire the synchronizer in shared
-     * mode.
-     */
-    private static class Sync extends AbstractQueuedSynchronizer
-    {
-        /**
-         * Attempts to acquire this synchronizer in shared mode. It may be acquired once it has been released.
-         *
-         * @param ignore This parameter is ignored.
-         *
-         * @return 1 if the shared acquisition succeeds and -1 if it fails.
-         */
-        protected int tryAcquireShared(int ignore)
-        {
-            return isSignalled() ? 1 : -1;
-        }
-
-        /**
-         * Releases the synchronizer, setting its internal state to 1.
-         *
-         * @param ignore This parameter is ignored.
-         *
-         * @return <tt>true</tt> always.
-         */
-        protected boolean tryReleaseShared(int ignore)
-        {
-            setState(1);
-
-            return true;
-        }
-
-        /**
-         * Tests if the synchronizer is signalled. It is signalled when its internal state it 1.
-         *
-         * @return <tt>true</tt> if the internal state is 1, <tt>false</tt> otherwise.
-         */
-        boolean isSignalled()
-        {
-            return getState() != 0;
-        }
-    }
-}