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