org.apache.hadoop.hdfs.protocol.datatransfer.Op Maven / Gradle / Ivy
/**
* 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.hadoop.hdfs.protocol.datatransfer;
import java.io.DataInput;
import java.io.DataOutput;
import java.io.IOException;
import org.apache.hadoop.classification.InterfaceAudience;
import org.apache.hadoop.classification.InterfaceStability;
/** Operation */
@InterfaceAudience.Private
@InterfaceStability.Evolving
public enum Op {
WRITE_BLOCK((byte)80),
READ_BLOCK((byte)81),
READ_METADATA((byte)82),
REPLACE_BLOCK((byte)83),
COPY_BLOCK((byte)84),
BLOCK_CHECKSUM((byte)85),
TRANSFER_BLOCK((byte)86),
REQUEST_SHORT_CIRCUIT_FDS((byte)87);
/** The code for this operation. */
public final byte code;
private Op(byte code) {
this.code = code;
}
private static final int FIRST_CODE = values()[0].code;
/** Return the object represented by the code. */
private static Op valueOf(byte code) {
final int i = (code & 0xff) - FIRST_CODE;
return i < 0 || i >= values().length? null: values()[i];
}
/** Read from in */
public static Op read(DataInput in) throws IOException {
return valueOf(in.readByte());
}
/** Write to out */
public void write(DataOutput out) throws IOException {
out.write(code);
}
}