1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one 3 * or more contributor license agreements. See the NOTICE file 4 * distributed with this work for additional information 5 * regarding copyright ownership. The ASF licenses this file 6 * to you under the Apache License, Version 2.0 (the 7 * "License"); you may not use this file except in compliance 8 * with the License. You may obtain a copy of the License at 9 * 10 * http://www.apache.org/licenses/LICENSE-2.0 11 * 12 * Unless required by applicable law or agreed to in writing, 13 * software distributed under the License is distributed on an 14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY 15 * KIND, either express or implied. See the License for the 16 * specific language governing permissions and limitations 17 * under the License. 18 */ 19 20 package org.apache.hadoop.hbase; 21 22 import java.io.IOException; 23 24 import org.apache.hadoop.hbase.classification.InterfaceAudience; 25 26 /** 27 * Coprocessor interface. 28 */ 29 @InterfaceAudience.Private 30 public interface Coprocessor { 31 int VERSION = 1; 32 33 /** Highest installation priority */ 34 int PRIORITY_HIGHEST = 0; 35 /** High (system) installation priority */ 36 int PRIORITY_SYSTEM = Integer.MAX_VALUE / 4; 37 /** Default installation priority for user coprocessors */ 38 int PRIORITY_USER = Integer.MAX_VALUE / 2; 39 /** Lowest installation priority */ 40 int PRIORITY_LOWEST = Integer.MAX_VALUE; 41 42 /** 43 * Lifecycle state of a given coprocessor instance. 44 */ 45 enum State { 46 UNINSTALLED, 47 INSTALLED, 48 STARTING, 49 ACTIVE, 50 STOPPING, 51 STOPPED 52 } 53 54 // Interface 55 void start(CoprocessorEnvironment env) throws IOException; 56 57 void stop(CoprocessorEnvironment env) throws IOException; 58 59 }