storm-client/src/jvm/org/apache/storm/messaging/netty/ControlMessage.java

/**
 * 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.storm.messaging.netty;

import org.apache.storm.shade.io.netty.buffer.ByteBuf;
import org.apache.storm.shade.io.netty.buffer.Unpooled;

public enum ControlMessage implements INettySerializable {
    CLOSE_MESSAGE((short) -100),
    EOB_MESSAGE((short) -201),
    OK_RESPONSE((short) -200),
    FAILURE_RESPONSE((short) -400),
    SASL_TOKEN_MESSAGE_REQUEST((short) -202),
    SASL_COMPLETE_REQUEST((short) -203);

    private final short code;

    ControlMessage(short code) {
        this.code = code;
    }

    /**
     * Create message.
     * @param encoded status code
     * @return a control message per an encoded status code
     */
    public static ControlMessage mkMessage(short encoded) {
        for (ControlMessage cm : ControlMessage.values()) {
            if (encoded == cm.code) {
                return cm;
            }
        }
        return null;
    }

    public static ControlMessage read(byte[] serial) {
        ByteBuf cmBuffer = Unpooled.wrappedBuffer(serial);
        try {
            return mkMessage(cmBuffer.getShort(0));
        } finally {
            cmBuffer.release();
        }
    }

    @Override
    public int encodeLength() {
        return 2; //short
    }

    @Override
    public void write(ByteBuf buf) {
        buf.writeShort(code);
    }
}