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35 package org.jruby;
36
37 import java.util.HashMap  ;
38 import java.util.Iterator ;
39 import java.util.Map ;
40 import org.jruby.runtime.ClassIndex;
41 import org.jruby.runtime.builtin.IRubyObject;
42 import org.jruby.runtime.marshal.UnmarshalStream;
43
44
48 public class RubySymbol extends RubyObject {
49 private final String symbol;
50 private final int id;
51
52 private RubySymbol(Ruby runtime, String symbol) {
53 super(runtime, runtime.getClass("Symbol"));
54 this.symbol = symbol;
55
56 runtime.symbolLastId++;
57 this.id = runtime.symbolLastId;
58 }
59
60 public int getNativeTypeIndex() {
61 return ClassIndex.SYMBOL;
62 }
63
64
68 public String asSymbol() {
69 return symbol;
70 }
71
72 public boolean isImmediate() {
73 return true;
74 }
75
76 public static String getSymbol(Ruby runtime, long id) {
77 RubySymbol result = runtime.getSymbolTable().lookup(id);
78 if (result != null) {
79 return result.symbol;
80 }
81 return null;
82 }
83
84
87
88 public static RubySymbol newSymbol(Ruby runtime, String name) {
89 RubySymbol result;
90 synchronized (RubySymbol.class) {
91
94 result = runtime.getSymbolTable().lookup(name);
95 if (result == null) {
96 result = new RubySymbol(runtime, name);
97 runtime.getSymbolTable().store(result);
98 }
99 }
100 return result;
101 }
102
103 public IRubyObject equal(IRubyObject other) {
104 return RubyBoolean.newBoolean(getRuntime(), this == other);
107 }
108
109 public RubyFixnum to_i() {
110 return getRuntime().newFixnum(id);
111 }
112
113 public IRubyObject inspect() {
114 return getRuntime().newString(":" +
115 (isSymbolName(symbol) ? symbol : getRuntime().newString(symbol).dump().toString()));
116 }
117
118 public IRubyObject to_s() {
119 return getRuntime().newString(symbol);
120 }
121
122 public RubyFixnum hash() {
123 return getRuntime().newFixnum(hashCode());
124 }
125
126 public int hashCode() {
127 return id;
128 }
129
130 public boolean equals(Object other) {
131 return other == this;
132 }
133
134 public IRubyObject to_sym() {
135 return this;
136 }
137
138 public IRubyObject freeze() {
139 return this;
140 }
141
142 public IRubyObject taint() {
143 return this;
144 }
145
146 private static boolean isIdentStart(char c) {
147 return ((c >= 'a' && c <= 'z')|| (c >= 'A' && c <= 'Z')
148 || c == '_');
149 }
150 private static boolean isIdentChar(char c) {
151 return ((c >= 'a' && c <= 'z') || (c >= '0' && c <= '9') || (c >= 'A' && c <= 'Z')
152 || c == '_');
153 }
154
155 private static boolean isIdentifier(String s) {
156 if (s == null || s.length() <= 0) {
157 return false;
158 }
159
160 if (!isIdentStart(s.charAt(0))) {
161 return false;
162 }
163 for (int i = 1; i < s.length(); i++) {
164 if (!isIdentChar(s.charAt(i))) {
165 return false;
166 }
167 }
168
169 return true;
170 }
171
172
177 private static boolean isSpecialGlobalName(String s) {
178 if (s == null || s.length() <= 0) {
179 return false;
180 }
181
182 int length = s.length();
183
184 switch (s.charAt(0)) {
185 case '~': case '*': case '$': case '?': case '!': case '@': case '/': case '\\':
186 case ';': case ',': case '.': case '=': case ':': case '<': case '>': case '\"':
187 case '&': case '`': case '\'': case '+': case '0':
188 return length == 1;
189 case '-':
190 return (length == 1 || (length == 2 && isIdentChar(s.charAt(1))));
191
192 default:
193 for (int i = 0; i < length; i++) {
195 if (!Character.isDigit(s.charAt(i))) {
196 return false;
197 }
198 }
199 }
200 return true;
201 }
202
203 private static boolean isSymbolName(String s) {
204 if (s == null || s.length() < 1) {
205 return false;
206 }
207
208 int length = s.length();
209
210 char c = s.charAt(0);
211 switch (c) {
212 case '$':
213 return length > 1 && isSpecialGlobalName(s.substring(1));
214 case '@':
215 int offset = 1;
216 if (length >= 2 && s.charAt(1) == '@') {
217 offset++;
218 }
219
220 return isIdentifier(s.substring(offset));
221 case '<':
222 return (length == 1 || (length == 2 && (s.equals("<<") || s.equals("<="))) ||
223 (length == 3 && s.equals("<=>")));
224 case '>':
225 return (length == 1) || (length == 2 && (s.equals(">>") || s.equals(">=")));
226 case '=':
227 return ((length == 2 && (s.equals("==") || s.equals("=~"))) ||
228 (length == 3 && s.equals("===")));
229 case '*':
230 return (length == 1 || (length == 2 && s.equals("**")));
231 case '+':
232 return (length == 1 || (length == 2 && s.equals("+@")));
233 case '-':
234 return (length == 1 || (length == 2 && s.equals("-@")));
235 case '|': case '^': case '&': case '/': case '%': case '~': case '`':
236 return length == 1;
237 case '[':
238 return s.equals("[]") || s.equals("[]=");
239 }
240
241 if (!isIdentStart(c)) {
242 return false;
243 }
244
245 boolean localID = (c >= 'a' && c <= 'z');
246 int last = 1;
247
248 for (; last < length; last++) {
249 char d = s.charAt(last);
250
251 if (!isIdentChar(d)) {
252 break;
253 }
254 }
255
256 if (last == length) {
257 return true;
258 } else if (localID && last == length - 1) {
259 char d = s.charAt(last);
260
261 return d == '!' || d == '?' || d == '=';
262 }
263
264 return false;
265 }
266
267
268
269 public static RubySymbol unmarshalFrom(UnmarshalStream input) throws java.io.IOException {
270 RubySymbol result = RubySymbol.newSymbol(input.getRuntime(), RubyString.byteListToString(input.unmarshalString()));
271 input.registerLinkTarget(result);
272 return result;
273 }
274
275 public static class SymbolTable {
276
277 private Map table = new HashMap ();
278
279 public IRubyObject[] all_symbols() {
280 int length = table.size();
281 IRubyObject[] array = new IRubyObject[length];
282 System.arraycopy(table.values().toArray(), 0, array, 0, length);
283 return array;
284 }
285
286 public RubySymbol lookup(long symbolId) {
287 Iterator iter = table.values().iterator();
288 while (iter.hasNext()) {
289 RubySymbol symbol = (RubySymbol) iter.next();
290 if (symbol != null) {
291 if (symbol.id == symbolId) {
292 return symbol;
293 }
294 }
295 }
296 return null;
297 }
298
299 public RubySymbol lookup(String name) {
300 return (RubySymbol) table.get(name);
301 }
302
303 public void store(RubySymbol symbol) {
304 table.put(symbol.asSymbol(), symbol);
305 }
306
307 }
308
309 }
310 |
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