org.springframework.yarn.batch.partition.StaticBatchPartitionHandler.java Source code

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Here is the source code for org.springframework.yarn.batch.partition.StaticBatchPartitionHandler.java

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/*
 * Copyright 2013 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.yarn.batch.partition;

import java.util.Set;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.batch.core.StepExecution;
import org.springframework.batch.core.partition.PartitionHandler;
import org.springframework.batch.core.partition.StepExecutionSplitter;
import org.springframework.yarn.batch.am.AbstractBatchAppmaster;

/**
 * Implementation of Spring Batch {@link PartitionHandler} which does
 * partitioning based on static grid size.
 *
 * @author Janne Valkealahti
 *
 */
public class StaticBatchPartitionHandler extends AbstractBatchPartitionHandler {

    private static final Log log = LogFactory.getLog(StaticBatchPartitionHandler.class);

    /** Grid size for partitioning */
    private int gridSize = 1;

    /**
     * Instantiates a new static batch partition handler.
     *
     * @param batchAppmaster the batch appmaster
     */
    public StaticBatchPartitionHandler(AbstractBatchAppmaster batchAppmaster) {
        super(batchAppmaster);
    }

    /**
     * Instantiates a new static batch partition handler.
     *
     * @param batchAppmaster the batch appmaster
     * @param gridSize the grid size
     */
    public StaticBatchPartitionHandler(AbstractBatchAppmaster batchAppmaster, int gridSize) {
        super(batchAppmaster);
        this.gridSize = gridSize;
    }

    /**
     * Passed to the {@link StepExecutionSplitter} in the
     * {@link #handle(StepExecutionSplitter, StepExecution)} method, instructing
     * it how many {@link StepExecution} instances are required, ideally. The
     * {@link StepExecutionSplitter} is allowed to ignore the grid size in the
     * case of a restart, since the input data partitions must be preserved.
     *
     * @param gridSize the number of step executions that will be created
     */
    public void setGridSize(int gridSize) {
        this.gridSize = gridSize;
    }

    @Override
    protected Set<StepExecution> createStepExecutionSplits(StepExecutionSplitter stepSplitter,
            StepExecution stepExecution) throws Exception {
        if (log.isDebugEnabled()) {
            log.debug("Creating splits for stepExecution=" + stepExecution + " with gridSize=" + gridSize);
        }
        return stepSplitter.split(stepExecution, gridSize);
    }

}