001/*
002 * Copyright 2012-2013 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.builder;
017
018import java.util.ArrayList;
019import java.util.List;
020
021import org.springframework.batch.core.Job;
022import org.springframework.batch.core.Step;
023import org.springframework.batch.core.job.SimpleJob;
024import org.springframework.batch.core.job.flow.JobExecutionDecider;
025import org.springframework.core.task.TaskExecutor;
026import org.springframework.util.Assert;
027
028/**
029 * @author Dave Syer
030 * 
031 * @since 2.2
032 * 
033 */
034public class SimpleJobBuilder extends JobBuilderHelper<SimpleJobBuilder> {
035
036        private List<Step> steps = new ArrayList<Step>();
037
038        private JobFlowBuilder builder;
039
040        /**
041         * Create a new builder initialized with any properties in the parent. The parent is copied, so it can be re-used.
042         * 
043         * @param parent the parent to use
044         */
045        public SimpleJobBuilder(JobBuilderHelper<?> parent) {
046                super(parent);
047        }
048
049        public Job build() {
050                if (builder != null) {
051                        return builder.end().build();
052                }
053                SimpleJob job = new SimpleJob(getName());
054                super.enhance(job);
055                job.setSteps(steps);
056                try {
057                        job.afterPropertiesSet();
058                }
059                catch (Exception e) {
060                        throw new JobBuilderException(e);
061                }
062                return job;
063        }
064
065        /**
066         * Start the job with this step.
067         * 
068         * @param step a step to start with
069         * @return this for fluent chaining
070         */
071        public SimpleJobBuilder start(Step step) {
072                if (steps.isEmpty()) {
073                        steps.add(step);
074                }
075                else {
076                        steps.set(0, step);
077                }
078                return this;
079        }
080
081        /**
082         * Branch into a flow conditional on the outcome of the current step.
083         * 
084         * @param pattern a pattern for the exit status of the current step
085         * @return a builder for fluent chaining
086         */
087        public FlowBuilder.TransitionBuilder<FlowJobBuilder> on(String pattern) {
088                Assert.state(steps.size() > 0, "You have to start a job with a step");
089                for (Step step : steps) {
090                        if (builder == null) {
091                                builder = new JobFlowBuilder(new FlowJobBuilder(this), step);
092                        }
093                        else {
094                                builder.next(step);
095                        }
096                }
097                return builder.on(pattern);
098        }
099
100        /**
101         * Start with this decider. Returns a flow builder and when the flow is ended a job builder will be returned to
102         * continue the job configuration if needed.
103         * 
104         * @param decider a decider to execute first
105         * @return builder for fluent chaining
106         */
107        public JobFlowBuilder start(JobExecutionDecider decider) {
108                if (builder == null) {
109                        builder = new JobFlowBuilder(new FlowJobBuilder(this), decider);
110                }
111                else {
112                        builder.start(decider);
113                }
114                if (!steps.isEmpty()) {
115                        steps.remove(0);
116                }
117                for (Step step : steps) {
118                        builder.next(step);
119                }
120                return builder;
121        }
122
123        /**
124         * Continue with this decider if the previous step was successful. Returns a flow builder and when the flow is ended
125         * a job builder will be returned to continue the job configuration if needed.
126         * 
127         * @param decider a decider to execute next
128         * @return builder for fluent chaining
129         */
130        public JobFlowBuilder next(JobExecutionDecider decider) {
131                for (Step step : steps) {
132                        if (builder == null) {
133                                builder = new JobFlowBuilder(new FlowJobBuilder(this), step);
134                        }
135                        else {
136                                builder.next(step);
137                        }
138                }
139                if (builder == null) {
140                        builder = new JobFlowBuilder(new FlowJobBuilder(this), decider);
141                }
142                else {
143                        builder.next(decider);
144                }
145                return builder;
146        }
147
148        /**
149         * Continue or end a job with this step if the previous step was successful.
150         * 
151         * @param step a step to execute next
152         * @return this for fluent chaining
153         */
154        public SimpleJobBuilder next(Step step) {
155                steps.add(step);
156                return this;
157        }
158
159        /**
160         * @param executor instance of {@link TaskExecutor} to be used.
161         * @return builder for fluent chaining
162         */
163        public JobFlowBuilder.SplitBuilder<FlowJobBuilder> split(TaskExecutor executor) {
164                for (Step step : steps) {
165                        if (builder == null) {
166                                builder = new JobFlowBuilder(new FlowJobBuilder(this), step);
167                        }
168                        else {
169                                builder.next(step);
170                        }
171                }
172                if (builder == null) {
173                        builder = new JobFlowBuilder(new FlowJobBuilder(this));
174                }
175                return builder.split(executor);
176        }
177
178}