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1   /*
2    * Copyright 2006-2011 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.builder;
17  
18  import org.springframework.batch.core.Job;
19  import org.springframework.batch.core.Step;
20  import org.springframework.batch.core.job.flow.Flow;
21  import org.springframework.batch.core.job.flow.FlowJob;
22  import org.springframework.batch.core.step.builder.StepBuilderException;
23  
24  /**
25   * A job builder for {@link FlowJob} instances. A flow job delegates processing to a nested flow composed of steps and
26   * conditional transitions between steps.
27   * 
28   * @author Dave Syer
29   * 
30   * @since 2.2
31   */
32  public class FlowJobBuilder extends JobBuilderHelper<FlowJobBuilder> {
33  
34  	private Flow flow;
35  
36  	/**
37  	 * Create a new builder initialized with any properties in the parent. The parent is copied, so it can be re-used.
38  	 * 
39  	 * @param parent a parent helper containing common job properties
40  	 */
41  	public FlowJobBuilder(JobBuilderHelper<?> parent) {
42  		super(parent);
43  	}
44  
45  	/**
46  	 * Start a job with this flow, but expect to transition from there to other flows or steps.
47  	 * 
48  	 * @param flow the flow to start with
49  	 * @return a builder to enable fluent chaining
50  	 */
51  	public JobFlowBuilder start(Flow flow) {
52  		return new JobFlowBuilder(this, flow);
53  	}
54  
55  	/**
56  	 * Start a job with this step, but expect to transition from there to other flows or steps.
57  	 * 
58  	 * @param step the step to start with
59  	 * @return a builder to enable fluent chaining
60  	 */
61  	public JobFlowBuilder start(Step step) {
62  		return new JobFlowBuilder(this, step);
63  	}
64  
65  	/**
66  	 * Provide a single flow to execute as the job.
67  	 * 
68  	 * @param flow the flow to execute
69  	 * @return this for fluent chaining
70  	 */
71  	protected FlowJobBuilder flow(Flow flow) {
72  		this.flow = flow;
73  		return this;
74  	}
75  
76  	/**
77  	 * Build a job that executes the flow provided, normally composed of other steps.
78  	 * 
79  	 * @return a flow job
80  	 */
81  	public Job build() {
82  		FlowJob job = new FlowJob();
83  		job.setName(getName());
84  		job.setFlow(flow);
85  		super.enhance(job);
86  		try {
87  			job.afterPropertiesSet();
88  		}
89  		catch (Exception e) {
90  			throw new StepBuilderException(e);
91  		}
92  		return job;
93  	}
94  
95  }