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1
11 package org.eclipse.core.internal.expressions;
12
13 import java.util.ArrayList  ;
14 import java.util.HashMap ;
15 import java.util.List ;
16 import java.util.Map ;
17
18 import org.eclipse.core.runtime.Assert;
19 import org.eclipse.core.runtime.CoreException;
20 import org.eclipse.core.runtime.IConfigurationElement;
21 import org.eclipse.core.runtime.IExtensionDelta;
22 import org.eclipse.core.runtime.IExtensionRegistry;
23 import org.eclipse.core.runtime.IRegistryChangeEvent;
24 import org.eclipse.core.runtime.IRegistryChangeListener;
25 import org.eclipse.core.runtime.Platform;
26
27 import org.eclipse.core.expressions.IPropertyTester;
28
29 public class TypeExtensionManager implements IRegistryChangeListener {
30
31 private String fExtensionPoint;
32
33 private static final String TYPE= "type";
35 private static final IPropertyTester[] EMPTY_PROPERTY_TESTER_ARRAY= new IPropertyTester[0];
36
37 private static final IPropertyTester NULL_PROPERTY_TESTER= new IPropertyTester() {
38 public boolean handles(String namespace, String property) {
39 return false;
40 }
41 public boolean isInstantiated() {
42 return true;
43 }
44 public boolean isDeclaringPluginActive() {
45 return true;
46 }
47 public IPropertyTester instantiate() throws CoreException {
48 return this;
49 }
50 public boolean test(Object receiver, String property, Object [] args, Object expectedValue) {
51 return false;
52 }
53 };
54
55
58 private Map fTypeExtensionMap;
59
60
63 private Map fConfigurationElementMap;
64
65
68 private PropertyCache fPropertyCache;
69
70
71 public TypeExtensionManager(String extensionPoint) {
72 Assert.isNotNull(extensionPoint);
73 fExtensionPoint= extensionPoint;
74 Platform.getExtensionRegistry().addRegistryChangeListener(this);
75 initializeCaches();
76 }
77
78 public Property getProperty(Object receiver, String namespace, String method) throws CoreException {
79 return getProperty(receiver, namespace, method, false);
80 }
81
82 public synchronized Property getProperty(Object receiver, String namespace, String method, boolean forcePluginActivation) throws CoreException {
83 long start= 0;
84 if (Expressions.TRACING)
85 start= System.currentTimeMillis();
86
87 Class clazz= receiver instanceof Class ? (Class )receiver : receiver.getClass();
89 Property result= new Property(clazz, namespace, method);
90 Property cached= fPropertyCache.get(result);
91 if (cached != null) {
92 if (cached.isValidCacheEntry(forcePluginActivation)) {
93 if (Expressions.TRACING) {
94 System.out.println("[Type Extension] - method " + clazz.getName() + "#" + method + " found in cache: " + (System.currentTimeMillis() - start) + " ms."); }
99 return cached;
100 }
101 fPropertyCache.remove(cached);
105 }
106 TypeExtension extension= get(clazz);
107 IPropertyTester extender= extension.findTypeExtender(this, namespace, method, receiver instanceof Class , forcePluginActivation);
108 if (extender == TypeExtension.CONTINUE || extender == null) {
109 throw new CoreException(new ExpressionStatus(
110 ExpressionStatus.TYPE_EXTENDER_UNKOWN_METHOD,
111 Messages.format(
112 ExpressionMessages.TypeExtender_unknownMethod,
113 new Object [] {method, clazz.toString()})));
114 }
115 result.setPropertyTester(extender);
116 fPropertyCache.put(result);
117 if (Expressions.TRACING) {
118 System.out.println("[Type Extension] - method " + clazz.getName() + "#" + method + " not found in cache: " + (System.currentTimeMillis() - start) + " ms."); }
123 return result;
124 }
125
126
130 TypeExtension get(Class clazz) {
131 TypeExtension result= (TypeExtension)fTypeExtensionMap.get(clazz);
132 if (result == null) {
133 result= new TypeExtension(clazz);
134 fTypeExtensionMap.put(clazz, result);
135 }
136 return result;
137 }
138
139
143 IPropertyTester[] loadTesters(Class type) {
144 if (fConfigurationElementMap == null) {
145 fConfigurationElementMap= new HashMap ();
146 IExtensionRegistry registry= Platform.getExtensionRegistry();
147 IConfigurationElement[] ces= registry.getConfigurationElementsFor(
148 ExpressionPlugin.getPluginId(),
149 fExtensionPoint);
150 for (int i= 0; i < ces.length; i++) {
151 IConfigurationElement config= ces[i];
152 String typeAttr= config.getAttribute(TYPE);
153 List typeConfigs= (List )fConfigurationElementMap.get(typeAttr);
154 if (typeConfigs == null) {
155 typeConfigs= new ArrayList ();
156 fConfigurationElementMap.put(typeAttr, typeConfigs);
157 }
158 typeConfigs.add(config);
159 }
160 }
161 String typeName= type.getName();
162 List typeConfigs= (List )fConfigurationElementMap.get(typeName);
163 if (typeConfigs == null)
164 return EMPTY_PROPERTY_TESTER_ARRAY;
165 else {
166 IPropertyTester[] result= new IPropertyTester[typeConfigs.size()];
167 for (int i= 0; i < result.length; i++) {
168 IConfigurationElement config= (IConfigurationElement)typeConfigs.get(i);
169 try {
170 result[i]= new PropertyTesterDescriptor(config);
171 } catch (CoreException e) {
172 ExpressionPlugin.getDefault().getLog().log(e.getStatus());
173 result[i]= NULL_PROPERTY_TESTER;
174 }
175 }
176 fConfigurationElementMap.remove(typeName);
177 return result;
178 }
179 }
180
181 public void registryChanged(IRegistryChangeEvent event) {
182 IExtensionDelta[] deltas= event.getExtensionDeltas(ExpressionPlugin.getPluginId(), fExtensionPoint);
183 if (deltas.length > 0) {
184 initializeCaches();
185 }
186 }
187
188 private synchronized void initializeCaches() {
189 fTypeExtensionMap= new HashMap ();
190 fConfigurationElementMap= null;
191 fPropertyCache= new PropertyCache(1000);
192 }
193 }
194 |
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