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 java.io.IOException; 23 24 import org.apache.hadoop.classification.InterfaceAudience; 25 26 27 /** 28 * A collection of interfaces and utilities used for interacting with custom RPC 29 * interfaces exposed by Coprocessors. 30 */ 31 @InterfaceAudience.Private 32 public abstract class Batch { 33 /** 34 * Defines a unit of work to be executed. 35 * 36 * <p> 37 * When used with 38 * {@link org.apache.hadoop.hbase.client.HTable#coprocessorService(Class, byte[], byte[], org.apache.hadoop.hbase.client.coprocessor.Batch.Call)} 39 * the implementations {@link Batch.Call#call(Object)} method will be invoked 40 * with a proxy to the 41 * {@link org.apache.hadoop.hbase.coprocessor.CoprocessorService} 42 * sub-type instance. 43 * </p> 44 * @see org.apache.hadoop.hbase.client.coprocessor 45 * @see org.apache.hadoop.hbase.client.HTable#coprocessorService(byte[]) 46 * @see org.apache.hadoop.hbase.client.HTable#coprocessorService(Class, byte[], byte[], org.apache.hadoop.hbase.client.coprocessor.Batch.Call) 47 * @param <T> the instance type to be passed to 48 * {@link Batch.Call#call(Object)} 49 * @param <R> the return type from {@link Batch.Call#call(Object)} 50 */ 51 public interface Call<T,R> { 52 R call(T instance) throws IOException; 53 } 54 55 /** 56 * Defines a generic callback to be triggered for each {@link Batch.Call#call(Object)} 57 * result. 58 * 59 * <p> 60 * When used with 61 * {@link org.apache.hadoop.hbase.client.HTable#coprocessorService(Class, byte[], byte[], org.apache.hadoop.hbase.client.coprocessor.Batch.Call)} 62 * the implementation's {@link Batch.Callback#update(byte[], byte[], Object)} 63 * method will be called with the {@link Batch.Call#call(Object)} return value 64 * from each region in the selected range. 65 * </p> 66 * @param <R> the return type from the associated {@link Batch.Call#call(Object)} 67 * @see org.apache.hadoop.hbase.client.HTable#coprocessorService(Class, byte[], byte[], org.apache.hadoop.hbase.client.coprocessor.Batch.Call) 68 */ 69 public interface Callback<R> { 70 void update(byte[] region, byte[] row, R result); 71 } 72 }