/*
* Copyright 2006-2007 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
*
* http://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
* @since 2.0
*/
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
* master 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 master 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<StepExecution> handle(StepExecutionSplitter stepSplitter, StepExecution stepExecution) throws Exception;
}