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1
19
20 package org.netbeans.lib.lexer;
21
22 import java.beans.PropertyChangeEvent  ;
23 import java.beans.PropertyChangeListener ;
24 import java.lang.ref.WeakReference ;
25 import java.util.ArrayList ;
26 import java.util.Collection ;
27 import java.util.Collections ;
28 import java.util.HashMap ;
29 import java.util.List ;
30 import java.util.WeakHashMap ;
31 import org.netbeans.api.lexer.InputAttributes;
32 import org.netbeans.api.lexer.Language;
33 import org.netbeans.api.lexer.LanguagePath;
34 import org.netbeans.api.lexer.Token;
35 import org.netbeans.api.lexer.TokenId;
36 import org.netbeans.spi.lexer.LanguageEmbedding;
37 import org.netbeans.spi.lexer.LanguageHierarchy;
38 import org.netbeans.spi.lexer.LanguageProvider;
39 import org.netbeans.spi.lexer.Lexer;
40 import org.netbeans.spi.lexer.LexerRestartInfo;
41 import org.openide.util.Lookup;
42 import org.openide.util.LookupEvent;
43 import org.openide.util.LookupListener;
44
45
49 public final class LanguageManager extends LanguageProvider implements LookupListener, PropertyChangeListener {
50
51 private static final Language<TokenId> NO_LANG = new LanguageHierarchy<TokenId>() {
52 @Override
53 protected Lexer<TokenId> createLexer(LexerRestartInfo<TokenId> info) {
54 return null;
55 }
56 @Override
57 protected Collection <TokenId> createTokenIds() {
58 return Collections.emptyList();
59 }
60 @Override
61 protected String mimeType() {
62 return "obscure/no-language-marker"; }
64 }.language();
65
66 private static final LanguageEmbedding<TokenId> NO_LANG_EMBEDDING
67 = LanguageEmbedding.create(NO_LANG, 0, 0);
68
69 private static LanguageManager instance = null;
70
71 public static synchronized LanguageManager getInstance() {
72 if (instance == null) {
73 instance = new LanguageManager();
74 }
75 return instance;
76 }
77
78 private Lookup.Result<LanguageProvider> lookupResult = null;
79
80 private List <LanguageProvider> providers = Collections.<LanguageProvider>emptyList();
81 private HashMap <String , WeakReference <Language<? extends TokenId>>> langCache
82 = new HashMap <String , WeakReference <Language<? extends TokenId>>>();
83 private WeakHashMap <Token, LanguageEmbedding<? extends TokenId>> tokenLangCache
84 = new WeakHashMap <Token, LanguageEmbedding<? extends TokenId>>();
85
86 private final String LOCK = new String ("LanguageManager.LOCK");
87
88
89 private LanguageManager() {
90 lookupResult = Lookup.getDefault().lookup(new Lookup.Template<LanguageProvider>(LanguageProvider.class));
91 lookupResult.addLookupListener(this);
92 refreshProviders();
93 }
94
95
99 public Language<? extends TokenId> findLanguage(String mimePath) {
100 synchronized(LOCK) {
101 WeakReference <Language<? extends TokenId>> ref = langCache.get(mimePath);
102 Language<? extends TokenId> lang = ref == null ? null : ref.get();
103
104 if (lang == null) {
105 for(LanguageProvider p : providers) {
106 if (null != (lang = p.findLanguage(mimePath))) {
107 break;
108 }
109 }
110
111 if (lang == null) {
112 lang = NO_LANG;
113 }
114
115 langCache.put(mimePath, new WeakReference <Language<? extends TokenId>>(lang));
116 }
117
118 return lang == NO_LANG ? null : lang;
119 }
120 }
121
122 public LanguageEmbedding<? extends TokenId> findLanguageEmbedding(
123 Token<? extends TokenId> token, LanguagePath languagePath, InputAttributes inputAttributes) {
124 synchronized(LOCK) {
125 LanguageEmbedding<? extends TokenId> lang = tokenLangCache.get(token);
126
127 if (lang == null) {
128 for(LanguageProvider p : providers) {
129 if (null != (lang = p.findLanguageEmbedding(token, languagePath, inputAttributes))) {
130 break;
131 }
132 }
133
134 if (lang == null) {
135 lang = NO_LANG_EMBEDDING;
136 }
137
138 tokenLangCache.put(token, lang);
139 }
140
141 return lang == NO_LANG_EMBEDDING ? null : lang;
142 }
143 }
144
145
149 public void resultChanged(LookupEvent ev) {
150 refreshProviders();
151 }
152
153
157 public void propertyChange(PropertyChangeEvent evt) {
158 if (evt.getPropertyName() == null) {
159 synchronized(LOCK) {
160 langCache.clear();
161 tokenLangCache.clear();
162 }
163 } else if (LanguageProvider.PROP_LANGUAGE.equals(evt.getPropertyName())) {
164 synchronized(LOCK) {
165 langCache.clear();
166 }
167 } else if (LanguageProvider.PROP_EMBEDDED_LANGUAGE.equals(evt.getPropertyName())) {
168 synchronized(LOCK) {
169 tokenLangCache.clear();
170 }
171 }
172 firePropertyChange(evt.getPropertyName());
174 }
175
176
180 private void refreshProviders() {
181 Collection <? extends LanguageProvider> newProviders = lookupResult.allInstances();
182
183 synchronized(LOCK) {
184 for(LanguageProvider p : providers) {
185 p.removePropertyChangeListener(this);
186 }
187
188 providers = new ArrayList <LanguageProvider>(newProviders);
189
190 for(LanguageProvider p : providers) {
191 p.addPropertyChangeListener(this);
192 }
193
194 langCache.clear();
195 tokenLangCache.clear();
196 }
197 }
198
199 }
200 |
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