1 package org.apache.turbine.modules.actions;
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22 import org.apache.turbine.modules.screens.TemplateScreen;
23 import org.apache.turbine.services.velocity.TurbineVelocity;
24 import org.apache.turbine.util.RunData;
25 import org.apache.turbine.util.velocity.VelocityActionEvent;
26 import org.apache.velocity.context.Context;
27
28 /***
29 * This class provides a convenience methods for Velocity Actions
30 * to use. Since this class is abstract, it should only be extended
31 * and not used directly.
32 *
33 * @author <a href="mailto:jon@latchkey.com">Jon S. Stevens</a>
34 * @author <a href="mailto:jvanzyl@periapt.com">Jason van Zyl</a>
35 * @version $Id: VelocityAction.java 534527 2007-05-02 16:10:59Z tv $
36 */
37 public abstract class VelocityAction extends VelocityActionEvent
38 {
39 /***
40 * You SHOULD NOT override this method and implement it in your
41 * action.
42 *
43 * @param data Turbine information.
44 * @throws Exception a generic exception.
45 */
46 public void doPerform(RunData data)
47 throws Exception
48 {
49 doPerform(data, getContext(data));
50 }
51
52 /***
53 * You SHOULD override this method and implement it in your
54 * action.
55 *
56 * @param data Turbine information.
57 * @param context Context for web pages.
58 * @throws Exception a generic exception.
59 */
60 public abstract void doPerform(RunData data,
61 Context context)
62 throws Exception;
63
64 /***
65 * Sets up the context and then calls super.perform(); thus,
66 * subclasses don't have to worry about getting a context
67 * themselves!
68 *
69 * @param data Turbine information.
70 * @throws Exception a generic exception.
71 */
72 protected void perform(RunData data)
73 throws Exception
74 {
75 super.perform(data);
76 }
77
78 /***
79 * This method is used when you want to short circuit an Action
80 * and change the template that will be executed next.
81 *
82 * @param data Turbine information.
83 * @param template The template that will be executed next.
84 */
85 public void setTemplate(RunData data,
86 String template)
87 {
88 TemplateScreen.setTemplate(data, template);
89 }
90
91 /***
92 * Return the Context needed by Velocity.
93 *
94 * @param data Turbine information.
95 * @return Context, a context for web pages.
96 */
97 protected Context getContext(RunData data)
98 {
99 return TurbineVelocity.getContext(data);
100 }
101 }