| /** |
| * 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), |
| RELEASE_SHORT_CIRCUIT_FDS((byte)88), |
| REQUEST_SHORT_CIRCUIT_SHM((byte)89), |
| CUSTOM((byte)127); |
| |
| /** The code for this operation. */ |
| public final byte code; |
| |
| 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); |
| } |
| } |