1 /*
2 * Copyright 2006-2007 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;
18
19 import java.util.Collection;
20
21 import org.springframework.batch.core.StepExecution;
22 import org.springframework.batch.item.ExecutionContext;
23
24 /**
25 * Interface defining the responsibilities of controlling the execution of a
26 * partitioned {@link StepExecution}. Implementations will need to create a
27 * partition with the {@link StepExecutionSplitter}, and then use an execution
28 * fabric (grid, etc.), to execute the partitioned step. The results of the
29 * executions can be returned raw from remote workers to be aggregated by the
30 * caller.
31 *
32 * @author Dave Syer
33 * @since 2.0
34 */
35 public interface PartitionHandler {
36
37 /**
38 * Main entry point for {@link PartitionHandler} interface. The splitter
39 * creates all the executions that need to be farmed out, along with their
40 * input parameters (in the form of their {@link ExecutionContext}). The
41 * master step execution is used to identify the partition and group
42 * together the results logically.
43 *
44 * @param stepSplitter a strategy for generating a collection of
45 * {@link StepExecution} instances
46 * @param stepExecution the master step execution for the whole partition
47 * @return a collection of completed {@link StepExecution} instances
48 * @throws Exception if anything goes wrong. This allows implementations to
49 * be liberal and rely on the caller to translate an exception into a step
50 * failure as necessary.
51 */
52 Collection<StepExecution> handle(StepExecutionSplitter stepSplitter, StepExecution stepExecution) throws Exception;
53
54 }