001/*
002 * Copyright 2006-2011 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.step.builder;
017
018import org.springframework.batch.core.Job;
019import org.springframework.batch.core.Step;
020import org.springframework.batch.core.launch.JobLauncher;
021import org.springframework.batch.core.launch.support.SimpleJobLauncher;
022import org.springframework.batch.core.step.job.JobParametersExtractor;
023import org.springframework.batch.core.step.job.JobStep;
024
025/**
026 * A step builder for {@link JobStep} instances. A job step executes a nested {@link Job} with parameters taken from the
027 * parent job or from the step execution.
028 * 
029 * @author Dave Syer
030 * 
031 * @since 2.2
032 */
033public class JobStepBuilder extends StepBuilderHelper<JobStepBuilder> {
034
035        private Job job;
036
037        private JobLauncher jobLauncher;
038
039        private JobParametersExtractor jobParametersExtractor;
040
041        /**
042         * Create a new builder initialized with any properties in the parent. The parent is copied, so it can be re-used.
043         * 
044         * @param parent a parent helper containing common step properties
045         */
046        public JobStepBuilder(StepBuilderHelper<?> parent) {
047                super(parent);
048        }
049
050        /**
051         * Provide a job to execute during the step.
052         * 
053         * @param job the job to execute
054         * @return this for fluent chaining
055         */
056        public JobStepBuilder job(Job job) {
057                this.job = job;
058                return this;
059        }
060
061        /**
062         * Add a job launcher. Defaults to a simple job launcher.
063         * 
064         * @param jobLauncher the job launcher to use
065         * @return this for fluent chaining
066         */
067        public JobStepBuilder launcher(JobLauncher jobLauncher) {
068                this.jobLauncher = jobLauncher;
069                return this;
070        }
071
072        /**
073         * Provide a job parameters extractor. Useful for extracting job parameters from the parent step execution context
074         * or job parameters.
075         * 
076         * @param jobParametersExtractor the job parameters extractor to use
077         * @return this for fluent chaining
078         */
079        public JobStepBuilder parametersExtractor(JobParametersExtractor jobParametersExtractor) {
080                this.jobParametersExtractor = jobParametersExtractor;
081                return this;
082        }
083
084        /**
085         * Build a step from the job provided.
086         * 
087         * @return a new job step
088         */
089        public Step build() {
090
091                JobStep step = new JobStep();
092                step.setName(getName());
093                super.enhance(step);
094                if (job != null) {
095                        step.setJob(job);
096                }
097                if (jobParametersExtractor != null) {
098                        step.setJobParametersExtractor(jobParametersExtractor);
099                }
100                if (jobLauncher == null) {
101                        SimpleJobLauncher jobLauncher = new SimpleJobLauncher();
102                        jobLauncher.setJobRepository(getJobRepository());
103                        try {
104                                jobLauncher.afterPropertiesSet();
105                        }
106                        catch (Exception e) {
107                                throw new StepBuilderException(e);
108                        }
109                        this.jobLauncher = jobLauncher;
110                }
111                step.setJobLauncher(jobLauncher);
112                try {
113                        step.afterPropertiesSet();
114                }
115                catch (Exception e) {
116                        throw new StepBuilderException(e);
117                }
118                return step;
119
120        }
121
122}