Creating a branch for experimenting with some ideas for JMS client.rajith_jms_client

git-svn-id: https://svn.apache.org/repos/asf/qpid/branches/rajith_jms_client@1128369 13f79535-47bb-0310-9956-ffa450edef68

1 files changed, 75 insertions, 0 deletions

diff --git a/qpid/java/client/src/main/java/org/apache/qpid/client/failover/FailoverNoopSupport.java b/qpid/java/client/src/main/java/org/apache/qpid/client/failover/FailoverNoopSupport.java
new file mode 100644
index 0000000000..51cc94965a
--- /dev/null
+++ b/qpid/java/client/src/main/java/org/apache/qpid/client/failover/FailoverNoopSupport.java
@@ -0,0 +1,75 @@
+/*
+ *  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.
+ *
+ *
+ */
+
+package org.apache.qpid.client.failover;
+
+import org.apache.qpid.client.AMQConnection;
+
+/**
+ * FailoverNoopSupport is a {@link FailoverSupport} implementation that does not really provide any failover support
+ * at all. It wraps a {@link FailoverProtectedOperation} but should that operation throw {@link FailoverException} this
+ * support class simply re-raises that exception as an IllegalStateException. This support wrapper should only be
+ * used where the caller can be certain that the failover protected operation cannot acutally throw a failover exception,
+ * for example, because the caller already holds a lock preventing that condition from arising.
+ *
+ * <p><table id="crc"><caption>CRC Card</caption>
+ * <tr><th> Responsibilities <th> Collaborations
+ * <tr><td> Perform a fail-over protected operation raising providing no handling of fail-over conditions.
+ * </table>
+ */
+public class FailoverNoopSupport<T, E extends Exception> implements FailoverSupport<T, E>
+{
+    /** The protected operation that is to be retried in the event of fail-over. */
+    FailoverProtectedOperation<T, E> operation;
+
+    /** The connection on which the fail-over protected operation is to be performed. */
+    AMQConnection connection;
+
+    /**
+     * Creates an automatic retrying fail-over handler for the specified operation.
+     *
+     * @param operation The fail-over protected operation to wrap in this handler.
+     */
+    public FailoverNoopSupport(FailoverProtectedOperation<T, E> operation, AMQConnection con)
+    {
+        this.operation = operation;
+        this.connection = con;
+    }
+
+    /**
+     * Delegates to another continuation which is to be provided with fail-over handling.
+     *
+     * @return The return value from the delegated to continuation.
+     * @throws E Any exception that the delegated to continuation may raise.
+     */
+    public T execute() throws E
+    {
+        try
+        {
+            return operation.execute();
+        }
+        catch (FailoverException e)
+        {
+            throw new IllegalStateException("Fail-over interupted no-op failover support. "
+                + "No-op support should only be used where the caller is certain fail-over cannot occur.", e);
+        }
+    }
+}