|
1
11
12 package org.eclipse.ui.internal.services;
13
14 import org.eclipse.core.expressions.Expression;
15 import org.eclipse.core.expressions.IEvaluationContext;
16 import org.eclipse.jface.util.IPropertyChangeListener;
17 import org.eclipse.jface.util.PropertyChangeEvent;
18 import org.eclipse.ui.ISourceProvider;
19
20
24 public final class EvaluationService implements IEvaluationService {
25
26 private EvaluationAuthority restrictionAuthority;
27 private EvaluationAuthority evaluationAuthority;
28
29 private IPropertyChangeListener restrictionListener = new IPropertyChangeListener() {
30
31 public void propertyChange(PropertyChangeEvent event) {
32 IEvaluationReference source = (IEvaluationReference) event
33 .getSource();
34 if (source == null)
35 return;
36
37 IEvaluationReference mappedReference = source.getTargetReference();
38 if (mappedReference == null)
39 return;
40
41 boolean evaluationEnabled = false;
42 if (event.getNewValue() != null) {
43 evaluationEnabled = ((Boolean  ) event.getNewValue()).booleanValue();
44 } else {
45 evaluationEnabled = false;
46 }
47 mappedReference.setPostingChanges(evaluationEnabled);
48 }
49 };
50
51
52 public EvaluationService() {
53 evaluationAuthority = new EvaluationAuthority();
54 restrictionAuthority = new EvaluationAuthority();
55 }
56
57
63 public IEvaluationReference addEvaluationListener(Expression expression,
64 IPropertyChangeListener listener, String property, Expression restrictEvaluation) {
65 IEvaluationReference expressionReference = new EvaluationReference(expression, listener, property, null);
66
67 evaluationAuthority.addEvaluationListener(expressionReference);
68 if (restrictEvaluation != null) {
69 IPropertyChangeListener restrictionListener = getRestrictionListener();
70 IEvaluationReference restrictRef = new EvaluationReference(
72 restrictEvaluation, restrictionListener,
73 "evaluate", expressionReference);
75 expressionReference.setTargetReference(restrictRef);
77 restrictionAuthority.addEvaluationListener(restrictRef);
78 }
79 return expressionReference;
80 }
81
82
85 private IPropertyChangeListener getRestrictionListener() {
86 return restrictionListener ;
87 }
88
89
94 public void removeEvaluationListener(IEvaluationReference ref) {
95 evaluationAuthority.removeEvaluationListener(ref);
96 IEvaluationReference target = ref.getTargetReference();
97 if (target != null) {
98 restrictionAuthority
99 .removeEvaluationListener(target);
100 }
101 }
102
103
108 public void addSourceProvider(ISourceProvider provider) {
109 restrictionAuthority.addSourceProvider(provider);
110 evaluationAuthority.addSourceProvider(provider);
111 }
112
113
118 public void removeSourceProvider(ISourceProvider provider) {
119 restrictionAuthority.removeSourceProvider(provider);
120 evaluationAuthority.removeSourceProvider(provider);
121 }
122
123
128 public void dispose() {
129 restrictionAuthority.dispose();
130 evaluationAuthority.dispose();
131 }
132
133
136 public IEvaluationContext getCurrentState() {
137 return evaluationAuthority.getCurrentState();
138 }
139
140
143 public void addServiceListener(IPropertyChangeListener listener) {
144 restrictionAuthority.addServiceListener(listener);
145 evaluationAuthority.addServiceListener(listener);
146 }
147
148
151 public void removeServiceListener(IPropertyChangeListener listener) {
152 restrictionAuthority.removeServiceListener(listener);
153 evaluationAuthority.removeServiceListener(listener);
154 }
155 } |
Popular Tags |
Java API By Example, From Geeks To Geeks.