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.Step;
019import org.springframework.batch.core.job.flow.Flow;
020import org.springframework.batch.core.job.flow.FlowStep;
021
022/**
023 * A step builder for {@link FlowStep} instances. A flow step delegates processing to a nested flow composed of other
024 * steps.
025 * 
026 * @author Dave Syer
027 * 
028 * @since 2.2
029 */
030public class FlowStepBuilder extends StepBuilderHelper<FlowStepBuilder> {
031
032        private Flow flow;
033
034        /**
035         * Create a new builder initialized with any properties in the parent. The parent is copied, so it can be re-used.
036         * 
037         * @param parent a parent helper containing common step properties
038         */
039        public FlowStepBuilder(StepBuilderHelper<?> parent) {
040                super(parent);
041        }
042
043        /**
044         * Provide a flow to execute during the step.
045         * 
046         * @param flow the flow to execute
047         * @return this for fluent chaining
048         */
049        public FlowStepBuilder flow(Flow flow) {
050                this.flow = flow;
051                return this;
052        }
053
054        /**
055         * Build a step that executes the flow provided, normally composed of other steps. The flow is not executed in a
056         * transaction because the individual steps are supposed to manage their own transaction state.
057         * 
058         * @return a flow step
059         */
060        public Step build() {
061                FlowStep step = new FlowStep();
062                step.setName(getName());
063                step.setFlow(flow);
064                super.enhance(step);
065                try {
066                        step.afterPropertiesSet();
067                }
068                catch (Exception e) {
069                        throw new StepBuilderException(e);
070                }
071                return step;
072        }
073
074}