1 /* 2 * 3 * Licensed to the Apache Software Foundation (ASF) under one 4 * or more contributor license agreements. See the NOTICE file 5 * distributed with this work for additional information 6 * regarding copyright ownership. The ASF licenses this file 7 * to you under the Apache License, Version 2.0 (the 8 * "License"); you may not use this file except in compliance 9 * with the License. You may obtain a copy of the License at 10 * 11 * http://www.apache.org/licenses/LICENSE-2.0 12 * 13 * Unless required by applicable law or agreed to in writing, software 14 * distributed under the License is distributed on an "AS IS" BASIS, 15 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 16 * See the License for the specific language governing permissions and 17 * limitations under the License. 18 */ 19 20 package org.apache.hadoop.hbase.client.coprocessor; 21 22 import org.apache.hadoop.classification.InterfaceAudience; 23 import org.apache.hadoop.classification.InterfaceStability; 24 25 import java.io.IOException; 26 27 28 /** 29 * A collection of interfaces and utilities used for interacting with custom RPC 30 * interfaces exposed by Coprocessors. 31 */ 32 @InterfaceAudience.Public 33 @InterfaceStability.Evolving 34 public abstract class Batch { 35 /** 36 * Defines a unit of work to be executed. 37 * 38 * <p> 39 * When used with 40 * {@link org.apache.hadoop.hbase.client.HTable#coprocessorService(Class, byte[], byte[], org.apache.hadoop.hbase.client.coprocessor.Batch.Call)} 41 * the implementations {@link Batch.Call#call(Object)} method will be invoked 42 * with a proxy to the 43 * {@link org.apache.hadoop.hbase.coprocessor.CoprocessorService} 44 * sub-type instance. 45 * </p> 46 * @see org.apache.hadoop.hbase.client.coprocessor 47 * @see org.apache.hadoop.hbase.client.HTable#coprocessorService(byte[]) 48 * @see org.apache.hadoop.hbase.client.HTable#coprocessorService(Class, byte[], byte[], org.apache.hadoop.hbase.client.coprocessor.Batch.Call) 49 * @param <T> the instance type to be passed to 50 * {@link Batch.Call#call(Object)} 51 * @param <R> the return type from {@link Batch.Call#call(Object)} 52 */ 53 public static interface Call<T,R> { 54 public R call(T instance) throws IOException; 55 } 56 57 /** 58 * Defines a generic callback to be triggered for each {@link Batch.Call#call(Object)} 59 * result. 60 * 61 * <p> 62 * When used with 63 * {@link org.apache.hadoop.hbase.client.HTable#coprocessorService(Class, byte[], byte[], org.apache.hadoop.hbase.client.coprocessor.Batch.Call)} 64 * the implementation's {@link Batch.Callback#update(byte[], byte[], Object)} 65 * method will be called with the {@link Batch.Call#call(Object)} return value 66 * from each region in the selected range. 67 * </p> 68 * @param <R> the return type from the associated {@link Batch.Call#call(Object)} 69 * @see org.apache.hadoop.hbase.client.HTable#coprocessorService(Class, byte[], byte[], org.apache.hadoop.hbase.client.coprocessor.Batch.Call) 70 */ 71 public static interface Callback<R> { 72 public void update(byte[] region, byte[] row, R result); 73 } 74 }