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1
11 package org.eclipse.jdt.internal.ui.wizards.buildpaths;
12
13 import java.util.HashMap  ;
14
15 import org.eclipse.core.runtime.CoreException;
16 import org.eclipse.core.runtime.IConfigurationElement;
17 import org.eclipse.core.runtime.ISafeRunnable;
18 import org.eclipse.core.runtime.IStatus;
19 import org.eclipse.core.runtime.Platform;
20 import org.eclipse.core.runtime.SafeRunner;
21 import org.eclipse.core.runtime.Status;
22
23 import org.eclipse.jdt.ui.JavaUI;
24 import org.eclipse.jdt.ui.wizards.ClasspathAttributeConfiguration;
25
26 import org.eclipse.jdt.internal.ui.JavaPlugin;
27 import org.eclipse.jdt.internal.ui.util.CoreUtility;
28
29 public class ClasspathAttributeConfigurationDescriptors {
30
31 private static class Descriptor {
32
33 private IConfigurationElement fConfigElement;
34 private ClasspathAttributeConfiguration fInstance;
35
36 private static final String ATT_NAME = "attributeName"; private static final String ATT_CLASS = "class";
39 public Descriptor(IConfigurationElement configElement) throws CoreException {
40 fConfigElement = configElement;
41 fInstance= null;
42
43 String name = configElement.getAttribute(ATT_NAME);
44 String pageClassName = configElement.getAttribute(ATT_CLASS);
45
46 if (name == null) {
47 throw new CoreException(new Status(IStatus.ERROR, JavaUI.ID_PLUGIN, 0, "Invalid extension (missing attributeName)", null)); }
49 if (pageClassName == null) {
50 throw new CoreException(new Status(IStatus.ERROR, JavaUI.ID_PLUGIN, 0, "Invalid extension (missing class name): " + name, null)); }
52 }
53
54 public ClasspathAttributeConfiguration getInstance() throws CoreException {
55 if (fInstance == null) {
56 Object elem= CoreUtility.createExtension(fConfigElement, ATT_CLASS);
57 if (elem instanceof ClasspathAttributeConfiguration) {
58 fInstance= (ClasspathAttributeConfiguration) elem;
59 } else {
60 throw new CoreException(new Status(IStatus.ERROR, JavaUI.ID_PLUGIN, 0, "Invalid extension (page not of type IClasspathContainerPage): " + getKey(), null)); }
62 }
63 return fInstance;
64 }
65
66 public String getKey() {
67 return fConfigElement.getAttribute(ATT_NAME);
68 }
69 }
70
71 private static final String ATT_EXTENSION = "classpathAttributeConfiguration";
73 private HashMap fDescriptors;
74
75 public ClasspathAttributeConfigurationDescriptors() {
76 fDescriptors= null;
77 }
78
79 private HashMap getDescriptors() {
80 if (fDescriptors == null) {
81 fDescriptors= readExtensions();
82 }
83 return fDescriptors;
84 }
85
86 public boolean containsKey(String attributeKey) {
87 return getDescriptors().containsKey(attributeKey);
88 }
89
90 public ClasspathAttributeConfiguration get(final String attributeKey) {
91 final Descriptor desc= (Descriptor) getDescriptors().get(attributeKey);
92 if (desc == null) {
93 return null;
94 }
95 final ClasspathAttributeConfiguration[] res= { null };
96 SafeRunner.run(new ISafeRunnable() {
97
98 public void handleException(Throwable exception) {
99 JavaPlugin.log(exception);
100 getDescriptors().remove(attributeKey); }
102
103 public void run() throws Exception {
104 res[0]= desc.getInstance();
105 }
106 });
107 return res[0];
108 }
109
110 private static HashMap readExtensions() {
111 IConfigurationElement[] elements = Platform.getExtensionRegistry().getConfigurationElementsFor(JavaUI.ID_PLUGIN, ATT_EXTENSION);
112 HashMap descriptors= new HashMap (elements.length * 2);
113 for (int i= 0; i < elements.length; i++) {
114 try {
115 Descriptor curr= new Descriptor(elements[i]);
116 descriptors.put(curr.getKey(), curr);
117 } catch (CoreException e) {
118 JavaPlugin.log(e);
119 }
120 }
121 return descriptors;
122 }
123
124 }
125 |
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