001/*
002 * Copyright 2006-2018 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.flow;
017
018import org.springframework.batch.core.JobExecution;
019import org.springframework.batch.core.StepExecution;
020import org.springframework.lang.Nullable;
021
022/**
023 * Interface allowing for programmatic access to the decision on what the status
024 * of a flow should be.  For example, if some condition that's stored in the 
025 * database indicates that the job should stop for a manual check, a decider
026 * implementation could check that value to determine the status of the flow. 
027 * 
028 * @author Dave Syer
029 * @author Mahmoud Ben Hassine
030 * @since 2.0
031 */
032public interface JobExecutionDecider {
033
034        /**
035         * Strategy for branching an execution based on the state of an ongoing
036         * {@link JobExecution}. The return value will be used as a status to
037         * determine the next step in the job.
038         * 
039         * @param jobExecution a job execution
040         * @param stepExecution the latest step execution (may be {@code null})
041         * @return the exit status code
042         */
043        FlowExecutionStatus decide(JobExecution jobExecution, @Nullable StepExecution stepExecution);
044
045}