org.springframework.batch.core.partition.PartitionHandler Maven / Gradle / Ivy

/*
 * Copyright 2006-2022 the original author or authors.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      https://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.springframework.batch.core.partition;

import java.util.Collection;

import org.springframework.batch.core.StepExecution;
import org.springframework.batch.item.ExecutionContext;

/**
 * Interface defining the responsibilities of controlling the execution of a partitioned
 * {@link StepExecution}. Implementations will need to create a partition with the
 * {@link StepExecutionSplitter}, and then use an execution fabric (grid, etc.), to
 * execute the partitioned step. The results of the executions can be returned raw from
 * remote workers to be aggregated by the caller.
 *
 * @author Dave Syer
 * @author Mahmoud Ben Hassine
 * @author Taeik Lim
 * @since 2.0
 */
@FunctionalInterface
public interface PartitionHandler {

	/**
	 * Main entry point for {@link PartitionHandler} interface. The splitter creates all
	 * the executions that need to be farmed out, along with their input parameters (in
	 * the form of their {@link ExecutionContext}). The manager step execution is used to
	 * identify the partition and group together the results logically.
	 * @param stepSplitter a strategy for generating a collection of {@link StepExecution}
	 * instances
	 * @param stepExecution the manager step execution for the whole partition
	 * @return a collection of completed {@link StepExecution} instances
	 * @throws Exception if anything goes wrong. This allows implementations to be liberal
	 * and rely on the caller to translate an exception into a step failure as necessary.
	 */
	Collection handle(StepExecutionSplitter stepSplitter, StepExecution stepExecution) throws Exception;

}