1 /*
2 * Copyright 2006-2013 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.step.tasklet;
17
18 import org.springframework.batch.core.ExitStatus;
19 import org.springframework.batch.core.StepContribution;
20 import org.springframework.batch.core.scope.context.ChunkContext;
21 import org.springframework.batch.item.adapter.AbstractMethodInvokingDelegator;
22 import org.springframework.batch.repeat.RepeatStatus;
23
24 /**
25 * A {@link Tasklet} that wraps a method in a POJO. By default the return
26 * value is {@link ExitStatus#COMPLETED} unless the delegate POJO itself returns
27 * an {@link ExitStatus}. The POJO method is usually going to have no arguments,
28 * but a static argument or array of arguments can be used by setting the
29 * arguments property.
30 *
31 * @see AbstractMethodInvokingDelegator
32 *
33 * @author Dave Syer
34 *
35 */
36 public class MethodInvokingTaskletAdapter extends AbstractMethodInvokingDelegator<Object> implements Tasklet {
37
38 /**
39 * Delegate execution to the target object and translate the return value to
40 * an {@link ExitStatus} by invoking a method in the delegate POJO. Ignores
41 * the {@link StepContribution} and the attributes.
42 *
43 * @see Tasklet#execute(StepContribution, ChunkContext)
44 */
45 @Override
46 public RepeatStatus execute(StepContribution contribution, ChunkContext chunkContext) throws Exception {
47 contribution.setExitStatus(mapResult(invokeDelegateMethod()));
48 return RepeatStatus.FINISHED;
49 }
50
51 /**
52 * If the result is an {@link ExitStatus} already just return that,
53 * otherwise return {@link ExitStatus#COMPLETED}.
54 *
55 * @param result the value returned by the delegate method
56 * @return an {@link ExitStatus} consistent with the result
57 */
58 protected ExitStatus mapResult(Object result) {
59 if (result instanceof ExitStatus) {
60 return (ExitStatus) result;
61 }
62 return ExitStatus.COMPLETED;
63 }
64
65 }