/*
 * Copyright 2011 Steve Coughlan.
 *
 * Licensed 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 com.google.bitcoin.core;

import java.io.IOException;
import java.io.OutputStream;

/**
 * Parent class for header only messages that don't have a payload.
 * Currently this includes getaddr, ping, verack as well as the special bitcoinj class UnknownMessage
 *
 * @author Steve Coughlan
 */
public abstract class EmptyMessage extends Message {

	public EmptyMessage() {
	}

	public EmptyMessage(NetworkParameters params) {
		super(params);
	}

	public EmptyMessage(NetworkParameters params, byte[] msg, int offset) throws ProtocolException {
		super(params, msg, offset);
	}

	@Override
	final protected void bitcoinSerializeToStream(OutputStream stream) throws IOException {
	}

	@Override
	int getMessageSize() {
		return 0;
	}

	/* (non-Javadoc)
	 * @see com.google.bitcoin.core.Message#parse()
	 */
	@Override
	void parse() throws ProtocolException {
	}
}

package com.google.bitcoin.core;

import java.io.IOException;
import java.io.OutputStream;

/**
 * Parent class for header only message that don't have a payload
 * @author git
 *
 */
public abstract class EmptyMessage extends Message {

	public EmptyMessage() {
	}

	public EmptyMessage(NetworkParameters params) {
		super(params);
	}

	public EmptyMessage(NetworkParameters params, byte[] msg, int offset, int protocolVersion) throws ProtocolException {
		super(params, msg, offset, protocolVersion);
	}

	public EmptyMessage(NetworkParameters params, byte[] msg, int offset) throws ProtocolException {
		super(params, msg, offset);
	}

	@Override
	final void bitcoinSerializeToStream(OutputStream stream) throws IOException {
	}

}

Simplify EmptyMessage. Gets to patch 0 from Steve.