1 files changed, 188 insertions, 0 deletions
diff --git a/qpid/java/amqp-1-0-common/src/main/java/org/apache/qpid/amqp_1_0/codec/AbstractDescribedTypeWriter.java b/qpid/java/amqp-1-0-common/src/main/java/org/apache/qpid/amqp_1_0/codec/AbstractDescribedTypeWriter.java
new file mode 100644
index 0000000000..6977a40902
--- /dev/null
+++ b/qpid/java/amqp-1-0-common/src/main/java/org/apache/qpid/amqp_1_0/codec/AbstractDescribedTypeWriter.java
@@ -0,0 +1,188 @@
+/*
+ *
+ * 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.amqp_1_0.codec;
+
+import java.nio.ByteBuffer;
+
+public abstract class AbstractDescribedTypeWriter<V> implements ValueWriter<V>
+{
+    private int _length;
+    private Registry _registry;
+    private static final int LARGE_COMPOUND_THRESHOLD_COUNT = 10;
+    private ValueWriter _delegate;
+    private static final byte DESCRIBED_TYPE = (byte)0;
+
+    public AbstractDescribedTypeWriter(final Registry registry)
+    {
+        _registry = registry;
+    }
+
+    enum State {
+        FORMAT_CODE,
+        DESCRIPTOR,
+        DESCRIBED,
+        DONE
+    }
+
+    private State _state = State.FORMAT_CODE;
+
+    public int writeToBuffer(ByteBuffer buffer)
+    {
+        final int length = _length;
+
+        if(length == -1)
+        {
+            writeFirstPass(buffer);
+        }
+        else
+        {
+
+            State state = _state;
+
+            switch(state)
+            {
+                case FORMAT_CODE:
+                    if(buffer.hasRemaining())
+                    {
+                        buffer.put(DESCRIBED_TYPE);
+                        state = State.DESCRIPTOR;
+                        _delegate = createDescriptorWriter();
+                    }
+                    else
+                    {
+                        break;
+                    }
+
+                case DESCRIPTOR:
+                    if(buffer.hasRemaining())
+                    {
+                        _delegate.writeToBuffer(buffer);
+                        if(_delegate.isComplete())
+                        {
+                            state = State.DESCRIBED;
+                            _delegate = createDescribedWriter();
+                        }
+                        else
+                        {
+                            break;
+                        }
+                    }
+                case DESCRIBED:
+                    if(buffer.hasRemaining())
+                    {
+                        _delegate.writeToBuffer(buffer);
+                        if(_delegate.isComplete())
+                        {
+                            state = State.DONE;
+                            _delegate = null;
+                        }
+                        else
+                        {
+                            break;
+                        }
+                    }
+
+            }
+
+            _state = state;
+
+        }
+
+        return _length;
+    }
+
+    private void writeFirstPass(ByteBuffer buffer)
+    {
+
+        int length = 1;
+        State state = State.FORMAT_CODE;
+
+        ValueWriter descriptorWriter = createDescriptorWriter();
+        if(buffer.hasRemaining())
+        {
+            buffer.put(DESCRIBED_TYPE);
+            state = State.DESCRIPTOR;
+            _delegate = descriptorWriter;
+        }
+        length += descriptorWriter.writeToBuffer(buffer);
+
+        ValueWriter describedWriter = createDescribedWriter();
+
+        if(descriptorWriter.isComplete())
+        {
+            state = State.DESCRIBED;
+            _delegate = describedWriter;
+        }
+
+        length += describedWriter.writeToBuffer(buffer);
+
+        if(describedWriter.isComplete())
+        {
+            _delegate = null;
+            state = State.DONE;
+        }
+
+        _state = state;
+        _length = length;
+    }
+
+    public void setValue(V value)
+    {
+        _length = -1;
+        _delegate = null;
+        _state = State.FORMAT_CODE;
+        onSetValue(value);
+    }
+
+    public void setRegistry(Registry registry)
+    {
+        _registry = registry;
+    }
+
+    protected Registry getRegistry()
+    {
+        return _registry;
+    }
+
+    protected abstract void onSetValue(final V value);
+
+    protected abstract void clear();
+
+    protected abstract ValueWriter createDescribedWriter();
+
+    protected abstract Object getDescriptor();
+
+    protected final ValueWriter createDescriptorWriter()
+    {
+        return getRegistry().getValueWriter(getDescriptor());
+    }
+
+    public boolean isComplete()
+    {
+        return _state == State.DONE;
+    }
+
+    public boolean isCacheable()
+    {
+        return false;
+    }
+}
+\ No newline at end of file