001/* 002 * Copyright 2006-2013 the original author or authors. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * https://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 */ 016 017package org.springframework.batch.core.resource; 018 019import org.springframework.batch.core.JobParameters; 020import org.springframework.batch.core.StepExecution; 021import org.springframework.batch.core.StepExecutionListener; 022import org.springframework.batch.core.listener.StepExecutionListenerSupport; 023import org.springframework.batch.repeat.CompletionPolicy; 024import org.springframework.batch.repeat.RepeatContext; 025import org.springframework.batch.repeat.RepeatStatus; 026import org.springframework.batch.repeat.policy.SimpleCompletionPolicy; 027import org.springframework.util.Assert; 028 029/** 030 * <p> 031 * A {@link CompletionPolicy} that picks up a commit interval from 032 * {@link JobParameters} by listening to the start of a step. Use anywhere that 033 * a {@link CompletionPolicy} can be used (usually at the chunk level in a 034 * step), and inject as a {@link StepExecutionListener} into the surrounding 035 * step. N.B. only after the step has started will the completion policy be 036 * usable. 037 * </p> 038 * 039 * <p> 040 * It is easier and probably preferable to simply declare the chunk with a 041 * commit-interval that is a late-binding expression (e.g. 042 * <code>#{jobParameters['commit.interval']}</code>). That feature is available 043 * from of Spring Batch 2.1.7. 044 * </p> 045 * 046 * @author Dave Syer 047 * 048 * @see CompletionPolicy 049 */ 050public class StepExecutionSimpleCompletionPolicy extends StepExecutionListenerSupport implements CompletionPolicy { 051 052 private CompletionPolicy delegate; 053 054 private String keyName = "commit.interval"; 055 056 /** 057 * Public setter for the key name of a Long value in the 058 * {@link JobParameters} that will contain a commit interval. Defaults to 059 * "commit.interval". 060 * @param keyName the keyName to set 061 */ 062 public void setKeyName(String keyName) { 063 this.keyName = keyName; 064 } 065 066 /** 067 * Set up a {@link SimpleCompletionPolicy} with a commit interval taken from 068 * the {@link JobParameters}. If there is a Long parameter with the given 069 * key name, the intValue of this parameter is used. If not an exception 070 * will be thrown. 071 * 072 * @see org.springframework.batch.core.listener.StepExecutionListenerSupport#beforeStep(org.springframework.batch.core.StepExecution) 073 */ 074 @Override 075 public void beforeStep(StepExecution stepExecution) { 076 JobParameters jobParameters = stepExecution.getJobParameters(); 077 Assert.state(jobParameters.getParameters().containsKey(keyName), 078 "JobParameters do not contain Long parameter with key=[" + keyName + "]"); 079 delegate = new SimpleCompletionPolicy(jobParameters.getLong(keyName).intValue()); 080 } 081 082 /** 083 * @return true if the commit interval has been reached or the result 084 * indicates completion 085 * @see CompletionPolicy#isComplete(RepeatContext, RepeatStatus) 086 */ 087 @Override 088 public boolean isComplete(RepeatContext context, RepeatStatus result) { 089 Assert.state(delegate != null, "The delegate resource has not been initialised. " 090 + "Remember to register this object as a StepListener."); 091 return delegate.isComplete(context, result); 092 } 093 094 /** 095 * @return if the commit interval has been reached 096 * @see org.springframework.batch.repeat.CompletionPolicy#isComplete(org.springframework.batch.repeat.RepeatContext) 097 */ 098 @Override 099 public boolean isComplete(RepeatContext context) { 100 Assert.state(delegate != null, "The delegate resource has not been initialised. " 101 + "Remember to register this object as a StepListener."); 102 return delegate.isComplete(context); 103 } 104 105 /** 106 * @return a new {@link RepeatContext} 107 * @see org.springframework.batch.repeat.CompletionPolicy#start(org.springframework.batch.repeat.RepeatContext) 108 */ 109 @Override 110 public RepeatContext start(RepeatContext parent) { 111 Assert.state(delegate != null, "The delegate resource has not been initialised. " 112 + "Remember to register this object as a StepListener."); 113 return delegate.start(parent); 114 } 115 116 /** 117 * @see org.springframework.batch.repeat.CompletionPolicy#update(org.springframework.batch.repeat.RepeatContext) 118 */ 119 @Override 120 public void update(RepeatContext context) { 121 Assert.state(delegate != null, "The delegate resource has not been initialised. " 122 + "Remember to register this object as a StepListener."); 123 delegate.update(context); 124 } 125 126 /** 127 * Delegates to the wrapped {@link CompletionPolicy} if set, otherwise 128 * returns the value of {@link #setKeyName(String)}. 129 */ 130 @Override 131 public String toString() { 132 return (delegate == null) ? keyName : delegate.toString(); 133 } 134 135}