Showing the changes to java/pkg/sun/io/Converters.java (1 of 18352 files). Show all
Unified · Split
| @@ -0,0 +1,341 @@ | |||
| 1 | /* | ||
| 2 | * Copyright (c) 1998, 2010, Oracle and/or its affiliates. All rights reserved. | ||
| 3 | * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. | ||
| 4 | * | ||
| 5 | * This code is free software; you can redistribute it and/or modify it | ||
| 6 | * under the terms of the GNU General Public License version 2 only, as | ||
| 7 | * published by the Free Software Foundation. Oracle designates this | ||
| 8 | * particular file as subject to the "Classpath" exception as provided | ||
| 9 | * by Oracle in the LICENSE file that accompanied this code. | ||
| 10 | * | ||
| 11 | * This code is distributed in the hope that it will be useful, but WITHOUT | ||
| 12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
| 13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | ||
| 14 | * version 2 for more details (a copy is included in the LICENSE file that | ||
| 15 | * accompanied this code). | ||
| 16 | * | ||
| 17 | * You should have received a copy of the GNU General Public License version | ||
| 18 | * 2 along with this work; if not, write to the Free Software Foundation, | ||
| 19 | * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. | ||
| 20 | * | ||
| 21 | * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA | ||
| 22 | * or visit www.oracle.com if you need additional information or have any | ||
| 23 | * questions. | ||
| 24 | */ | ||
| 25 | |||
| 26 | package sun.io; | ||
| 27 | |||
| 28 | import java.io.UnsupportedEncodingException; | ||
| 29 | import java.lang.ref.SoftReference; | ||
| 30 | import java.util.Properties; | ||
| 31 | |||
| 32 | /** | ||
| 33 | * Package-private utility class that caches the default converter classes and | ||
| 34 | * provides other logic common to both the ByteToCharConverter and | ||
| 35 | * CharToByteConverter classes. | ||
| 36 | * | ||
| 37 | * @author Mark Reinhold | ||
| 38 | * @since 1.2 | ||
| 39 | * | ||
| 40 | * @deprecated Replaced by {@link java.nio.charset}. THIS API WILL BE | ||
| 41 | * REMOVED IN J2SE 1.6. | ||
| 42 | */ | ||
| 43 | @Deprecated | ||
| 44 | public class Converters { | ||
| 45 | |||
| 46 | private Converters() { } /* To prevent instantiation */ | ||
| 47 | |||
| 48 | /* Lock for all static fields in this class */ | ||
| 49 | private static Object lock = Converters.class; | ||
| 50 | |||
| 51 | /* Cached values of system properties */ | ||
| 52 | private static String converterPackageName = null; /* file.encoding.pkg */ | ||
| 53 | private static String defaultEncoding = null; /* file.encoding */ | ||
| 54 | |||
| 55 | /* Converter type constants and names */ | ||
| 56 | public static final int BYTE_TO_CHAR = 0; | ||
| 57 | public static final int CHAR_TO_BYTE = 1; | ||
| 58 | private static final String[] converterPrefix = { "ByteToChar", | ||
| 59 | "CharToByte" }; | ||
| 60 | |||
| 61 | |||
| 62 | // -- Converter class cache -- | ||
| 63 | |||
| 64 | private static final int CACHE_SIZE = 3; | ||
| 65 | |||
| 66 | /* For the default charset, whatever it turns out to be */ | ||
| 67 | private static final Object DEFAULT_NAME = new Object(); | ||
| 68 | |||
| 69 | /* Cached converter classes, CACHE_SIZE per converter type. Each cache | ||
| 70 | * entry is a soft reference to a two-object array; the first element of | ||
| 71 | * the array is the converter class, the second is an object (typically a | ||
| 72 | * string) representing the encoding name that was used to request the | ||
| 73 | * converter, e.g., | ||
| 74 | * | ||
| 75 | * ((Object[])classCache[CHAR_TO_BYTE][i].get())[0] | ||
| 76 | * | ||
| 77 | * will be a CharToByteConverter and | ||
| 78 | * | ||
| 79 | * ((Object[])classCache[CHAR_TO_BYTE][i].get())[1] | ||
| 80 | * | ||
| 81 | * will be the string encoding name used to request it, assuming that cache | ||
| 82 | * entry i is valid. | ||
| 83 | * | ||
| 84 | * Ordinarily we'd do this with a private static utility class, but since | ||
| 85 | * this code can be involved in the startup sequence it's important to keep | ||
| 86 | * the footprint down. | ||
| 87 | */ | ||
| 88 | @SuppressWarnings("unchecked") | ||
| 89 | private static SoftReference<Object[]>[][] classCache | ||
| 90 | = (SoftReference<Object[]>[][]) new SoftReference<?>[][] { | ||
| 91 | new SoftReference<?>[CACHE_SIZE], | ||
| 92 | new SoftReference<?>[CACHE_SIZE] | ||
| 93 | }; | ||
| 94 | |||
| 95 | private static void moveToFront(Object[] oa, int i) { | ||
| 96 | Object ob = oa[i]; | ||
| 97 | for (int j = i; j > 0; j--) | ||
| 98 | oa[j] = oa[j - 1]; | ||
| 99 | oa[0] = ob; | ||
| 100 | } | ||
| 101 | |||
| 102 | private static Class<?> cache(int type, Object encoding) { | ||
| 103 | SoftReference<Object[]>[] srs = classCache[type]; | ||
| 104 | for (int i = 0; i < CACHE_SIZE; i++) { | ||
| 105 | SoftReference<Object[]> sr = srs[i]; | ||
| 106 | if (sr == null) | ||
| 107 | continue; | ||
| 108 | Object[] oa = sr.get(); | ||
| 109 | if (oa == null) { | ||
| 110 | srs[i] = null; | ||
| 111 | continue; | ||
| 112 | } | ||
| 113 | if (oa[1].equals(encoding)) { | ||
| 114 | moveToFront(srs, i); | ||
| 115 | return (Class<?>)oa[0]; | ||
| 116 | } | ||
| 117 | } | ||
| 118 | return null; | ||
| 119 | } | ||
| 120 | |||
| 121 | private static Class<?> cache(int type, Object encoding, Class<?> c) { | ||
| 122 | SoftReference<Object[]>[] srs = classCache[type]; | ||
| 123 | srs[CACHE_SIZE - 1] = new SoftReference<>(new Object[] { c, encoding }); | ||
| 124 | moveToFront(srs, CACHE_SIZE - 1); | ||
| 125 | return c; | ||
| 126 | } | ||
| 127 | |||
| 128 | /* Used to avoid doing expensive charset lookups for charsets that are not | ||
| 129 | * yet directly supported by NIO. | ||
| 130 | */ | ||
| 131 | public static boolean isCached(int type, String encoding) { | ||
| 132 | synchronized (lock) { | ||
| 133 | SoftReference<Object[]>[] srs = classCache[type]; | ||
| 134 | for (int i = 0; i < CACHE_SIZE; i++) { | ||
| 135 | SoftReference<Object[]> sr = srs[i]; | ||
| 136 | if (sr == null) | ||
| 137 | continue; | ||
| 138 | Object[] oa = sr.get(); | ||
| 139 | if (oa == null) { | ||
| 140 | srs[i] = null; | ||
| 141 | continue; | ||
| 142 | } | ||
| 143 | if (oa[1].equals(encoding)) | ||
| 144 | return true; | ||
| 145 | } | ||
| 146 | return false; | ||
| 147 | } | ||
| 148 | } | ||
| 149 | |||
| 150 | |||
| 151 | |||
| 152 | /** Get the name of the converter package */ | ||
| 153 | private static String getConverterPackageName() { | ||
| 154 | String cp = converterPackageName; | ||
| 155 | if (cp != null) return cp; | ||
| 156 | java.security.PrivilegedAction<String> pa = | ||
| 157 | new sun.security.action.GetPropertyAction("file.encoding.pkg"); | ||
| 158 | cp = java.security.AccessController.doPrivileged(pa); | ||
| 159 | if (cp != null) { | ||
| 160 | /* Property is set, so take it as the true converter package */ | ||
| 161 | converterPackageName = cp; | ||
| 162 | } else { | ||
| 163 | /* Fall back to sun.io */ | ||
| 164 | cp = "sun.io"; | ||
| 165 | } | ||
| 166 | return cp; | ||
| 167 | } | ||
| 168 | |||
| 169 | public static String getDefaultEncodingName() { | ||
| 170 | synchronized (lock) { | ||
| 171 | if (defaultEncoding == null) { | ||
| 172 | java.security.PrivilegedAction<String> pa = | ||
| 173 | new sun.security.action.GetPropertyAction("file.encoding"); | ||
| 174 | defaultEncoding = java.security.AccessController.doPrivileged(pa); | ||
| 175 | } | ||
| 176 | } | ||
| 177 | return defaultEncoding; | ||
| 178 | } | ||
| 179 | |||
| 180 | public static void resetDefaultEncodingName() { | ||
| 181 | // This method should only be called during VM initialization. | ||
| 182 | if (sun.misc.VM.isBooted()) | ||
| 183 | return; | ||
| 184 | |||
| 185 | synchronized (lock) { | ||
| 186 | defaultEncoding = "ISO-8859-1"; | ||
| 187 | Properties p = System.getProperties(); | ||
| 188 | p.setProperty("file.encoding", defaultEncoding); | ||
| 189 | System.setProperties(p); | ||
| 190 | } | ||
| 191 | } | ||
| 192 | |||
| 193 | /** | ||
| 194 | * Get the class that implements the given type of converter for the named | ||
| 195 | * encoding, or throw an UnsupportedEncodingException if no such class can | ||
| 196 | * be found | ||
| 197 | */ | ||
| 198 | private static Class<?> getConverterClass(int type, String encoding) | ||
| 199 | throws UnsupportedEncodingException | ||
| 200 | { | ||
| 201 | String enc = null; | ||
| 202 | |||
| 203 | /* "ISO8859_1" is the canonical name for the ISO-Latin-1 encoding. | ||
| 204 | Native code in the JDK commonly uses the alias "8859_1" instead of | ||
| 205 | "ISO8859_1". We hardwire this alias here in order to avoid loading | ||
| 206 | the full alias table just for this case. */ | ||
| 207 | if (!encoding.equals("ISO8859_1")) { | ||
| 208 | if (encoding.equals("8859_1")) { | ||
| 209 | enc = "ISO8859_1"; | ||
| 210 | /* | ||
| 211 | * On Solaris with nl_langinfo() called in GetJavaProperties(): | ||
| 212 | * | ||
| 213 | * locale undefined -> NULL -> hardcoded default | ||
| 214 | * "C" locale -> "" -> hardcoded default (on 2.6) | ||
| 215 | * "C" locale -> "646" (on 2.7) | ||
| 216 | * "en_US" locale -> "ISO8859-1" | ||
| 217 | * "en_GB" locale -> "ISO8859-1" (on 2.7) | ||
| 218 | * "en_UK" locale -> "ISO8859-1" (on 2.6) | ||
| 219 | */ | ||
| 220 | } else if (encoding.equals("ISO8859-1")) { | ||
| 221 | enc = "ISO8859_1"; | ||
| 222 | } else if (encoding.equals("646")) { | ||
| 223 | enc = "ASCII"; | ||
| 224 | } else { | ||
| 225 | enc = CharacterEncoding.aliasName(encoding); | ||
| 226 | } | ||
| 227 | } | ||
| 228 | if (enc == null) { | ||
| 229 | enc = encoding; | ||
| 230 | } | ||
| 231 | |||
| 232 | try { | ||
| 233 | return Class.forName(getConverterPackageName() | ||
| 234 | + "." + converterPrefix[type] + enc); | ||
| 235 | } catch(ClassNotFoundException e) { | ||
| 236 | throw new UnsupportedEncodingException(enc); | ||
| 237 | } | ||
| 238 | |||
| 239 | } | ||
| 240 | |||
| 241 | /** | ||
| 242 | * Instantiate the given converter class, or throw an | ||
| 243 | * UnsupportedEncodingException if it cannot be instantiated | ||
| 244 | */ | ||
| 245 | private static Object newConverter(String enc, Class<?> c) | ||
| 246 | throws UnsupportedEncodingException | ||
| 247 | { | ||
| 248 | try { | ||
| 249 | return c.newInstance(); | ||
| 250 | } catch(InstantiationException e) { | ||
| 251 | throw new UnsupportedEncodingException(enc); | ||
| 252 | } catch(IllegalAccessException e) { | ||
| 253 | throw new UnsupportedEncodingException(enc); | ||
| 254 | } | ||
| 255 | } | ||
| 256 | |||
| 257 | /** | ||
| 258 | * Create a converter object that implements the given type of converter | ||
| 259 | * for the given encoding, or throw an UnsupportedEncodingException if no | ||
| 260 | * appropriate converter class can be found and instantiated | ||
| 261 | */ | ||
| 262 | static Object newConverter(int type, String enc) | ||
| 263 | throws UnsupportedEncodingException | ||
| 264 | { | ||
| 265 | Class<?> c; | ||
| 266 | synchronized (lock) { | ||
| 267 | c = cache(type, enc); | ||
| 268 | if (c == null) { | ||
| 269 | c = getConverterClass(type, enc); | ||
| 270 | if (!c.getName().equals("sun.io.CharToByteUTF8")) | ||
| 271 | cache(type, enc, c); | ||
| 272 | } | ||
| 273 | } | ||
| 274 | return newConverter(enc, c); | ||
| 275 | } | ||
| 276 | |||
| 277 | /** | ||
| 278 | * Find the class that implements the given type of converter for the | ||
| 279 | * default encoding. If the default encoding cannot be determined or is | ||
| 280 | * not yet defined, return a class that implements the fallback default | ||
| 281 | * encoding, which is just ISO 8859-1. | ||
| 282 | */ | ||
| 283 | private static Class<?> getDefaultConverterClass(int type) { | ||
| 284 | boolean fillCache = false; | ||
| 285 | Class<?> c; | ||
| 286 | |||
| 287 | /* First check the class cache */ | ||
| 288 | c = cache(type, DEFAULT_NAME); | ||
| 289 | if (c != null) | ||
| 290 | return c; | ||
| 291 | |||
| 292 | /* Determine the encoding name */ | ||
| 293 | String enc = getDefaultEncodingName(); | ||
| 294 | if (enc != null) { | ||
| 295 | /* file.encoding has been set, so cache the converter class */ | ||
| 296 | fillCache = true; | ||
| 297 | } else { | ||
| 298 | /* file.encoding has not been set, so use a default encoding which | ||
| 299 | will not be cached */ | ||
| 300 | enc = "ISO8859_1"; | ||
| 301 | } | ||
| 302 | |||
| 303 | /* We have an encoding name; try to find its class */ | ||
| 304 | try { | ||
| 305 | c = getConverterClass(type, enc); | ||
| 306 | if (fillCache) { | ||
| 307 | cache(type, DEFAULT_NAME, c); | ||
| 308 | } | ||
| 309 | } catch (UnsupportedEncodingException x) { | ||
| 310 | /* Can't find the default class, so fall back to ISO 8859-1 */ | ||
| 311 | try { | ||
| 312 | c = getConverterClass(type, "ISO8859_1"); | ||
| 313 | } catch (UnsupportedEncodingException y) { | ||
| 314 | throw new InternalError("Cannot find default " | ||
| 315 | + converterPrefix[type] | ||
| 316 | + " converter class"); | ||
| 317 | } | ||
| 318 | } | ||
| 319 | return c; | ||
| 320 | |||
| 321 | } | ||
| 322 | |||
| 323 | /** | ||
| 324 | * Create a converter object that implements the given type of converter | ||
| 325 | * for the default encoding, falling back to ISO 8859-1 if the default | ||
| 326 | * encoding cannot be determined. | ||
| 327 | */ | ||
| 328 | static Object newDefaultConverter(int type) { | ||
| 329 | Class<?> c; | ||
| 330 | synchronized (lock) { | ||
| 331 | c = getDefaultConverterClass(type); | ||
| 332 | } | ||
| 333 | try { | ||
| 334 | return newConverter("", c); | ||
| 335 | } catch (UnsupportedEncodingException x) { | ||
| 336 | throw new InternalError("Cannot instantiate default converter" | ||
| 337 | + " class " + c.getName()); | ||
| 338 | } | ||
| 339 | } | ||
| 340 | |||
| 341 | } | ||