1 /*
2 * Copyright 1999-2001,2004 The Apache Software Foundation.
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.apache.commons.workflow.core;
18
19
20 import java.util.EmptyStackException;
21 import org.apache.commons.workflow.BlockState;
22 import org.apache.commons.workflow.Context;
23 import org.apache.commons.workflow.Iterator;
24 import org.apache.commons.workflow.Step;
25 import org.apache.commons.workflow.StepException;
26 import org.apache.commons.workflow.base.BaseStep;
27
28
29 /**
30 * <p>Locate the closest surrounding Iterator, set the nesting control
31 * to <code>true</code>, and transfer control to the Iterator.</p>
32 *
33 * @version $Revision: 155475 $ $Date: 2005-02-26 13:31:11 +0000 (Sat, 26 Feb 2005) $
34 * @author Craig R. McClanahan
35 */
36
37 public class ContinueStep extends BaseStep {
38
39
40 // ----------------------------------------------------------= Constructors
41
42
43 /**
44 * Construct a default instance of this Step.
45 */
46 public ContinueStep() {
47
48 super();
49
50 }
51
52
53 /**
54 * Construct an instance of this Step with the specified identifier.
55 *
56 * @param id Step identifier
57 */
58 public ContinueStep(String id) {
59
60 super();
61 setId(id);
62
63 }
64
65
66 // --------------------------------------------------------- Public Methods
67
68
69 /**
70 * Perform the executable actions related to this Step, in the context of
71 * the specified Context.
72 *
73 * @param context The Context that is tracking our execution state
74 *
75 * @exception StepException if a processing error has occurred
76 */
77 public void execute(Context context) throws StepException {
78
79 // Locate the closest surrounding Iterator's BlockState
80 BlockState state = null;
81 while (true) {
82 try {
83 state = context.peekBlockState();
84 if (state.getBlock() instanceof Iterator)
85 break;
86 context.popBlockState();
87 continue;
88 } catch (EmptyStackException e) {
89 throw new StepException("Must be nested in an Iterator Block",
90 this);
91 }
92 }
93
94 // Set the nesting repeat indicator, and transfer control
95 state.setNest(true);
96 context.setNextStep(state.getBlock());
97
98 }
99
100
101 /**
102 * Render a string representation of this Step.
103 */
104 public String toString() {
105
106 StringBuffer sb = new StringBuffer("<core:continue");
107 if (getId() != null) {
108 sb.append(" id=\"");
109 sb.append(getId());
110 sb.append("\"");
111 }
112 sb.append("/>");
113 return (sb.toString());
114
115 }
116
117
118 }