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 */ 016package org.springframework.batch.core.job.flow.support.state; 017 018import java.util.Collection; 019import java.util.Collections; 020 021import org.springframework.batch.core.job.flow.FlowExecution; 022import org.springframework.batch.core.job.flow.FlowExecutionStatus; 023 024/** 025 * Implementation of the {@link FlowExecutionAggregator} interface that aggregates 026 * {@link FlowExecutionStatus}', using the status with the high precedence as the 027 * aggregate status. See {@link FlowExecutionStatus} for details on status 028 * precedence. 029 * 030 * @author Dave Syer 031 * @since 2.0 032 */ 033public class MaxValueFlowExecutionAggregator implements FlowExecutionAggregator { 034 035 /** 036 * Aggregate all of the {@link FlowExecutionStatus}es of the 037 * {@link FlowExecution}s into one status. The aggregate status will be the 038 * status with the highest precedence. 039 * 040 * @see FlowExecutionAggregator#aggregate(Collection) 041 */ 042 @Override 043 public FlowExecutionStatus aggregate(Collection<FlowExecution> executions) { 044 if (executions == null || executions.size() == 0) { 045 return FlowExecutionStatus.UNKNOWN; 046 } 047 return Collections.max(executions).getStatus(); 048 } 049 050}