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.repeat.policy;
18
19 import org.springframework.batch.repeat.RepeatContext;
20 import org.springframework.batch.repeat.context.RepeatContextSupport;
21
22 /**
23 * Termination policy that times out after a fixed period. Allows graceful exit
24 * from a batch if the latest result comes in after the timeout expires (i.e.
25 * does not throw a timeout exception).<br/>
26 *
27 * N.B. It may often be the case that the batch governed by this policy will be
28 * transactional, and the transaction might have its own timeout. In this case
29 * the transaction might throw a timeout exception on commit if its timeout
30 * threshold is lower than the termination policy.
31 *
32 * @author Dave Syer
33 *
34 */
35 public class TimeoutTerminationPolicy extends CompletionPolicySupport {
36
37 /**
38 * Default timeout value in millisecs (the value equivalent to 30 seconds).
39 */
40 public static final long DEFAULT_TIMEOUT = 30000L;
41
42 private long timeout = DEFAULT_TIMEOUT;
43
44 /**
45 * Default constructor.
46 */
47 public TimeoutTerminationPolicy() {
48 super();
49 }
50
51 /**
52 * Construct a {@link TimeoutTerminationPolicy} with the specified timeout
53 * value (in milliseconds).
54 *
55 * @param timeout
56 */
57 public TimeoutTerminationPolicy(long timeout) {
58 super();
59 this.timeout = timeout;
60 }
61
62 /**
63 * Check the timeout and complete gracefully if it has expires.
64 *
65 * @see org.springframework.batch.repeat.CompletionPolicy#isComplete(org.springframework.batch.repeat.RepeatContext)
66 */
67 @Override
68 public boolean isComplete(RepeatContext context) {
69 return ((TimeoutBatchContext) context).isComplete();
70 }
71
72 /**
73 * Start the clock on the timeout.
74 *
75 * @see org.springframework.batch.repeat.CompletionPolicy#start(RepeatContext)
76 */
77 @Override
78 public RepeatContext start(RepeatContext context) {
79 return new TimeoutBatchContext(context);
80 }
81
82 protected class TimeoutBatchContext extends RepeatContextSupport {
83
84 private volatile long time = System.currentTimeMillis();
85
86 private final long timeout = TimeoutTerminationPolicy.this.timeout;
87
88 public TimeoutBatchContext(RepeatContext context) {
89 super(context);
90 }
91
92 public boolean isComplete() {
93 return (System.currentTimeMillis() - time) > timeout;
94 }
95
96 }
97
98 }