01: /*
02: * (c) Copyright 2006 by Volker Bergmann. All rights reserved.
03: *
04: * Redistribution and use in source and binary forms, with or without
05: * modification, is permitted under the terms of the
06: * GNU General Public License.
07: *
08: * For redistributing this software or a derivative work under a license other
09: * than the GPL-compatible Free Software License as defined by the Free
10: * Software Foundation or approved by OSI, you must first obtain a commercial
11: * license to this software product from Volker Bergmann.
12: *
13: * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
14: * WITHOUT A WARRANTY OF ANY KIND. ALL EXPRESS OR IMPLIED CONDITIONS,
15: * REPRESENTATIONS AND WARRANTIES, INCLUDING ANY IMPLIED WARRANTY OF
16: * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE OR NON-INFRINGEMENT, ARE
17: * HEREBY EXCLUDED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
18: * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
19: * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
20: * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
21: * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
22: * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
23: * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
24: * POSSIBILITY OF SUCH DAMAGE.
25: */
26:
27: package org.databene.task;
28:
29: import org.databene.commons.Context;
30:
31: /**
32: * The Task interface.
33: * General usage is to call init() for initialization,
34: * then once or several times the run() method for executing the task's work.
35: * After usage, destroy() is called.
36: * If the goal of a Task has been achieved by external influences or Task
37: * completion, the Task may signal that it does not require further execution
38: * by returning false in {@link #wantsToRun()}.
39: * When implementing the Task interface, you should preferably inherit from
40: * {@link AbstractTask}, this may compensate for future interface changes.<br/>
41: * <br/>
42: * Created: 06.07.2007 06:30:22
43: * @author Volker Bergmann
44: */
45: public interface Task extends Runnable {
46:
47: /** @return the name of the task. */
48: String getTaskName();
49:
50: /** initializes the task and, if necessary, stores a reference to the context. */
51: void init(Context context);
52:
53: /**
54: * tells if the task still wants to be executed.
55: * @since 0.4.0
56: */
57: boolean wantsToRun();
58:
59: /** executes the main functionality of the task. */
60: void run();
61:
62: /** closes the task and releases all resources. */
63: void destroy();
64: }
|