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1   /*
2    * Copyright 2006-2013 the original author or authors.
3    *
4    * Licensed under the Apache License, Version 2.0 (the "License");
5    * you may not use this file except in compliance with the License.
6    * You may obtain a copy of the License at
7    *
8    *      http://www.apache.org/licenses/LICENSE-2.0
9    *
10   * Unless required by applicable law or agreed to in writing, software
11   * distributed under the License is distributed on an "AS IS" BASIS,
12   * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13   * See the License for the specific language governing permissions and
14   * limitations under the License.
15   */
16  
17  package org.springframework.batch.core.partition.support;
18  
19  import java.util.HashMap;
20  import java.util.Map;
21  
22  import org.springframework.batch.item.ExecutionContext;
23  
24  /**
25   * Simplest possible implementation of {@link Partitioner}. Just creates a set
26   * of empty {@link ExecutionContext} instances, and labels them as
27   * <code>{partition0, partition1, ..., partitionN}</code>, where <code>N</code> is the grid
28   * size.
29   *
30   * @author Dave Syer
31   * @since 2.0
32   */
33  public class SimplePartitioner implements Partitioner {
34  
35  	private static final String PARTITION_KEY = "partition";
36  
37  	@Override
38  	public Map<String, ExecutionContext> partition(int gridSize) {
39  		Map<String, ExecutionContext> map = new HashMap<String, ExecutionContext>(gridSize);
40  		for (int i = 0; i < gridSize; i++) {
41  			map.put(PARTITION_KEY + i, new ExecutionContext());
42  		}
43  		return map;
44  	}
45  
46  }