| 1 | /* |
| 2 | * Copyright 2006-2007 the original author or authors. |
| 3 | * |
| 4 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 5 | * you may not use this file except in compliance with the License. |
| 6 | * You may obtain a copy of the License at |
| 7 | * |
| 8 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 9 | * |
| 10 | * Unless required by applicable law or agreed to in writing, software |
| 11 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 12 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 13 | * See the License for the specific language governing permissions and |
| 14 | * limitations under the License. |
| 15 | */ |
| 16 | package org.springframework.batch.core.job.flow.support.state; |
| 17 | |
| 18 | import java.util.Collection; |
| 19 | import java.util.Collections; |
| 20 | |
| 21 | import org.springframework.batch.core.job.flow.FlowExecution; |
| 22 | import org.springframework.batch.core.job.flow.FlowExecutionStatus; |
| 23 | |
| 24 | /** |
| 25 | * Implementation of the {@link FlowExecutionAggregator} interface that aggregates |
| 26 | * {@link FlowExecutionStatus}', using the status with the high precedence as the |
| 27 | * aggregate status. See {@link FlowExecutionStatus} for details on status |
| 28 | * precedence. |
| 29 | * |
| 30 | * @author Dave Syer |
| 31 | * @since 2.0 |
| 32 | */ |
| 33 | public class MaxValueFlowExecutionAggregator implements FlowExecutionAggregator { |
| 34 | |
| 35 | /** |
| 36 | * Aggregate all of the {@link FlowExecutionStatus}es of the |
| 37 | * {@link FlowExecution}s into one status. The aggregate status will be the |
| 38 | * status with the highest precedence. |
| 39 | * |
| 40 | * @see FlowExecutionAggregator#aggregate(Collection) |
| 41 | */ |
| 42 | public FlowExecutionStatus aggregate(Collection<FlowExecution> executions) { |
| 43 | if (executions == null || executions.size() == 0) { |
| 44 | return FlowExecutionStatus.UNKNOWN; |
| 45 | } |
| 46 | return Collections.max(executions).getStatus(); |
| 47 | } |
| 48 | |
| 49 | } |