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Diffstat (limited to 'qpid/java/common/src/main/java/org/apache/mina/filter/codec/OurCumulativeProtocolDecoder.java')
| -rw-r--r-- | qpid/java/common/src/main/java/org/apache/mina/filter/codec/OurCumulativeProtocolDecoder.java | 197 |
1 files changed, 0 insertions, 197 deletions
diff --git a/qpid/java/common/src/main/java/org/apache/mina/filter/codec/OurCumulativeProtocolDecoder.java b/qpid/java/common/src/main/java/org/apache/mina/filter/codec/OurCumulativeProtocolDecoder.java deleted file mode 100644 index 3f7e206cb4..0000000000 --- a/qpid/java/common/src/main/java/org/apache/mina/filter/codec/OurCumulativeProtocolDecoder.java +++ /dev/null @@ -1,197 +0,0 @@ -/* - * 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.mina.filter.codec; - -import org.apache.mina.common.ByteBuffer; -import org.apache.mina.common.IoSession; - -/** - * A {@link ProtocolDecoder} that cumulates the content of received - * buffers to a <em>cumulative buffer</em> to help users implement decoders. - * <p> - * If the received {@link ByteBuffer} is only a part of a message. - * decoders should cumulate received buffers to make a message complete or - * to postpone decoding until more buffers arrive. - * <p> - * Here is an example decoder that decodes CRLF terminated lines into - * <code>Command</code> objects: - * <pre> - * public class CRLFTerminatedCommandLineDecoder - * extends CumulativeProtocolDecoder { - * - * private Command parseCommand(ByteBuffer in) { - * // Convert the bytes in the specified buffer to a - * // Command object. - * ... - * } - * - * protected boolean doDecode(IoSession session, ByteBuffer in, - * ProtocolDecoderOutput out) - * throws Exception { - * - * // Remember the initial position. - * int start = in.position(); - * - * // Now find the first CRLF in the buffer. - * byte previous = 0; - * while (in.hasRemaining()) { - * byte current = in.get(); - * - * if (previous == '\r' && current == '\n') { - * // Remember the current position and limit. - * int position = in.position(); - * int limit = in.limit(); - * try { - * in.position(start); - * in.limit(position); - * // The bytes between in.position() and in.limit() - * // now contain a full CRLF terminated line. - * out.write(parseCommand(in.slice())); - * } finally { - * // Set the position to point right after the - * // detected line and set the limit to the old - * // one. - * in.position(position); - * in.limit(limit); - * } - * // Decoded one line; CumulativeProtocolDecoder will - * // call me again until I return false. So just - * // return true until there are no more lines in the - * // buffer. - * return true; - * } - * - * previous = current; - * } - * - * // Could not find CRLF in the buffer. Reset the initial - * // position to the one we recorded above. - * in.position(start); - * - * return false; - * } - * } - * </pre> - * - * @author The Apache Directory Project (mina-dev@directory.apache.org) - * @version $Rev: 619823 $, $Date: 2008-02-08 10:09:37 +0000 (Fri, 08 Feb 2008) $ - */ -public abstract class OurCumulativeProtocolDecoder extends ProtocolDecoderAdapter { - - private static final String BUFFER = OurCumulativeProtocolDecoder.class - .getName() - + ".Buffer"; - - /** - * Creates a new instance. - */ - protected OurCumulativeProtocolDecoder() { - } - - /** - * Cumulates content of <tt>in</tt> into internal buffer and forwards - * decoding request to {@link #doDecode(IoSession, ByteBuffer, ProtocolDecoderOutput)}. - * <tt>doDecode()</tt> is invoked repeatedly until it returns <tt>false</tt> - * and the cumulative buffer is NOT compacted after decoding ends. - * - * @throws IllegalStateException if your <tt>doDecode()</tt> returned - * <tt>true</tt> not consuming the cumulative buffer. - */ - public void decode(IoSession session, ByteBuffer in, - ProtocolDecoderOutput out) throws Exception { - boolean usingSessionBuffer = true; - ByteBuffer buf = (ByteBuffer) session.getAttribute(BUFFER); - // If we have a session buffer, append data to that; otherwise - // use the buffer read from the network directly. - if (buf != null) { - buf.put(in); - buf.flip(); - } else { - buf = in; - usingSessionBuffer = false; - } - - for (;;) { - int oldPos = buf.position(); - boolean decoded = doDecode(session, buf, out); - if (decoded) { - if (buf.position() == oldPos) { - throw new IllegalStateException( - "doDecode() can't return true when buffer is not consumed."); - } - - if (!buf.hasRemaining()) { - break; - } - } else { - break; - } - } - - - // if there is any data left that cannot be decoded, we store - // it in a buffer in the session and next time this decoder is - // invoked the session buffer gets appended to - if (buf.hasRemaining()) { - storeRemainingInSession(buf, session); - } else { - if (usingSessionBuffer) - removeSessionBuffer(session); - } - } - - /** - * Implement this method to consume the specified cumulative buffer and - * decode its content into message(s). - * - * @param in the cumulative buffer - * @return <tt>true</tt> if and only if there's more to decode in the buffer - * and you want to have <tt>doDecode</tt> method invoked again. - * Return <tt>false</tt> if remaining data is not enough to decode, - * then this method will be invoked again when more data is cumulated. - * @throws Exception if cannot decode <tt>in</tt>. - */ - protected abstract boolean doDecode(IoSession session, ByteBuffer in, - ProtocolDecoderOutput out) throws Exception; - - /** - * Releases the cumulative buffer used by the specified <tt>session</tt>. - * Please don't forget to call <tt>super.dispose( session )</tt> when - * you override this method. - */ - public void dispose(IoSession session) throws Exception { - removeSessionBuffer(session); - } - - private void removeSessionBuffer(IoSession session) { - ByteBuffer buf = (ByteBuffer) session.removeAttribute(BUFFER); - if (buf != null) { - buf.release(); - } - } - - private void storeRemainingInSession(ByteBuffer buf, IoSession session) { - ByteBuffer remainingBuf = ByteBuffer.allocate(buf.capacity()); - remainingBuf.setAutoExpand(true); - remainingBuf.order(buf.order()); - remainingBuf.put(buf); - session.setAttribute(BUFFER, remainingBuf); - } -} |