Properties.java revision 404b64a5388f2811182e3180d8cd5a1a473a08b0
1/* 2 * Copyright (C) 2014 The Android Open Source Project 3 * Copyright (c) 1995, 2010, Oracle and/or its affiliates. All rights reserved. 4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 5 * 6 * This code is free software; you can redistribute it and/or modify it 7 * under the terms of the GNU General Public License version 2 only, as 8 * published by the Free Software Foundation. Oracle designates this 9 * particular file as subject to the "Classpath" exception as provided 10 * by Oracle in the LICENSE file that accompanied this code. 11 * 12 * This code is distributed in the hope that it will be useful, but WITHOUT 13 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 14 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 15 * version 2 for more details (a copy is included in the LICENSE file that 16 * accompanied this code). 17 * 18 * You should have received a copy of the GNU General Public License version 19 * 2 along with this work; if not, write to the Free Software Foundation, 20 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 21 * 22 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 23 * or visit www.oracle.com if you need additional information or have any 24 * questions. 25 */ 26 27package java.util; 28 29import java.io.IOException; 30import java.io.PrintStream; 31import java.io.PrintWriter; 32import java.io.InputStream; 33import java.io.OutputStream; 34import java.io.Reader; 35import java.io.Writer; 36import java.io.OutputStreamWriter; 37import java.io.BufferedWriter; 38 39/** 40 * The <code>Properties</code> class represents a persistent set of 41 * properties. The <code>Properties</code> can be saved to a stream 42 * or loaded from a stream. Each key and its corresponding value in 43 * the property list is a string. 44 * <p> 45 * A property list can contain another property list as its 46 * "defaults"; this second property list is searched if 47 * the property key is not found in the original property list. 48 * <p> 49 * Because <code>Properties</code> inherits from <code>Hashtable</code>, the 50 * <code>put</code> and <code>putAll</code> methods can be applied to a 51 * <code>Properties</code> object. Their use is strongly discouraged as they 52 * allow the caller to insert entries whose keys or values are not 53 * <code>Strings</code>. The <code>setProperty</code> method should be used 54 * instead. If the <code>store</code> or <code>save</code> method is called 55 * on a "compromised" <code>Properties</code> object that contains a 56 * non-<code>String</code> key or value, the call will fail. Similarly, 57 * the call to the <code>propertyNames</code> or <code>list</code> method 58 * will fail if it is called on a "compromised" <code>Properties</code> 59 * object that contains a non-<code>String</code> key. 60 * 61 * <p> 62 * The {@link #load(java.io.Reader) load(Reader)} <tt>/</tt> 63 * {@link #store(java.io.Writer, java.lang.String) store(Writer, String)} 64 * methods load and store properties from and to a character based stream 65 * in a simple line-oriented format specified below. 66 * 67 * The {@link #load(java.io.InputStream) load(InputStream)} <tt>/</tt> 68 * {@link #store(java.io.OutputStream, java.lang.String) store(OutputStream, String)} 69 * methods work the same way as the load(Reader)/store(Writer, String) pair, except 70 * the input/output stream is encoded in ISO 8859-1 character encoding. 71 * Characters that cannot be directly represented in this encoding can be written using 72 * Unicode escapes as defined in section 3.3 of 73 * <cite>The Java™ Language Specification</cite>; 74 * only a single 'u' character is allowed in an escape 75 * sequence. The native2ascii tool can be used to convert property files to and 76 * from other character encodings. 77 * 78 * <p> The {@link #loadFromXML(InputStream)} and {@link 79 * #storeToXML(OutputStream, String, String)} methods load and store properties 80 * in a simple XML format. By default the UTF-8 character encoding is used, 81 * however a specific encoding may be specified if required. An XML properties 82 * document has the following DOCTYPE declaration: 83 * 84 * <pre> 85 * <!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd"> 86 * </pre> 87 * Note that the system URI (http://java.sun.com/dtd/properties.dtd) is 88 * <i>not</i> accessed when exporting or importing properties; it merely 89 * serves as a string to uniquely identify the DTD, which is: 90 * <pre> 91 * <?xml version="1.0" encoding="UTF-8"?> 92 * 93 * <!-- DTD for properties --> 94 * 95 * <!ELEMENT properties ( comment?, entry* ) > 96 * 97 * <!ATTLIST properties version CDATA #FIXED "1.0"> 98 * 99 * <!ELEMENT comment (#PCDATA) > 100 * 101 * <!ELEMENT entry (#PCDATA) > 102 * 103 * <!ATTLIST entry key CDATA #REQUIRED> 104 * </pre> 105 * 106 * <p>This class is thread-safe: multiple threads can share a single 107 * <tt>Properties</tt> object without the need for external synchronization. 108 * 109 * @see <a href="{@docRoot}/../technotes/tools/solaris/native2ascii.html">native2ascii tool for Solaris</a> 110 * @see <a href="{@docRoot}/../technotes/tools/windows/native2ascii.html">native2ascii tool for Windows</a> 111 * 112 * @author Arthur van Hoff 113 * @author Michael McCloskey 114 * @author Xueming Shen 115 * @since JDK1.0 116 */ 117public 118class Properties extends Hashtable<Object,Object> { 119 /** 120 * use serialVersionUID from JDK 1.1.X for interoperability 121 */ 122 private static final long serialVersionUID = 4112578634029874840L; 123 124 /** 125 * A property list that contains default values for any keys not 126 * found in this property list. 127 * 128 * @serial 129 */ 130 protected Properties defaults; 131 132 /** 133 * Creates an empty property list with no default values. 134 */ 135 public Properties() { 136 this(null); 137 } 138 139 /** 140 * Creates an empty property list with the specified defaults. 141 * 142 * @param defaults the defaults. 143 */ 144 public Properties(Properties defaults) { 145 this.defaults = defaults; 146 } 147 148 /** 149 * Calls the <tt>Hashtable</tt> method <code>put</code>. Provided for 150 * parallelism with the <tt>getProperty</tt> method. Enforces use of 151 * strings for property keys and values. The value returned is the 152 * result of the <tt>Hashtable</tt> call to <code>put</code>. 153 * 154 * @param key the key to be placed into this property list. 155 * @param value the value corresponding to <tt>key</tt>. 156 * @return the previous value of the specified key in this property 157 * list, or <code>null</code> if it did not have one. 158 * @see #getProperty 159 * @since 1.2 160 */ 161 public synchronized Object setProperty(String key, String value) { 162 return put(key, value); 163 } 164 165 166 /** 167 * Reads a property list (key and element pairs) from the input 168 * character stream in a simple line-oriented format. 169 * <p> 170 * Properties are processed in terms of lines. There are two 171 * kinds of line, <i>natural lines</i> and <i>logical lines</i>. 172 * A natural line is defined as a line of 173 * characters that is terminated either by a set of line terminator 174 * characters (<code>\n</code> or <code>\r</code> or <code>\r\n</code>) 175 * or by the end of the stream. A natural line may be either a blank line, 176 * a comment line, or hold all or some of a key-element pair. A logical 177 * line holds all the data of a key-element pair, which may be spread 178 * out across several adjacent natural lines by escaping 179 * the line terminator sequence with a backslash character 180 * <code>\</code>. Note that a comment line cannot be extended 181 * in this manner; every natural line that is a comment must have 182 * its own comment indicator, as described below. Lines are read from 183 * input until the end of the stream is reached. 184 * 185 * <p> 186 * A natural line that contains only white space characters is 187 * considered blank and is ignored. A comment line has an ASCII 188 * <code>'#'</code> or <code>'!'</code> as its first non-white 189 * space character; comment lines are also ignored and do not 190 * encode key-element information. In addition to line 191 * terminators, this format considers the characters space 192 * (<code>' '</code>, <code>'\u0020'</code>), tab 193 * (<code>'\t'</code>, <code>'\u0009'</code>), and form feed 194 * (<code>'\f'</code>, <code>'\u000C'</code>) to be white 195 * space. 196 * 197 * <p> 198 * If a logical line is spread across several natural lines, the 199 * backslash escaping the line terminator sequence, the line 200 * terminator sequence, and any white space at the start of the 201 * following line have no affect on the key or element values. 202 * The remainder of the discussion of key and element parsing 203 * (when loading) will assume all the characters constituting 204 * the key and element appear on a single natural line after 205 * line continuation characters have been removed. Note that 206 * it is <i>not</i> sufficient to only examine the character 207 * preceding a line terminator sequence to decide if the line 208 * terminator is escaped; there must be an odd number of 209 * contiguous backslashes for the line terminator to be escaped. 210 * Since the input is processed from left to right, a 211 * non-zero even number of 2<i>n</i> contiguous backslashes 212 * before a line terminator (or elsewhere) encodes <i>n</i> 213 * backslashes after escape processing. 214 * 215 * <p> 216 * The key contains all of the characters in the line starting 217 * with the first non-white space character and up to, but not 218 * including, the first unescaped <code>'='</code>, 219 * <code>':'</code>, or white space character other than a line 220 * terminator. All of these key termination characters may be 221 * included in the key by escaping them with a preceding backslash 222 * character; for example,<p> 223 * 224 * <code>\:\=</code><p> 225 * 226 * would be the two-character key <code>":="</code>. Line 227 * terminator characters can be included using <code>\r</code> and 228 * <code>\n</code> escape sequences. Any white space after the 229 * key is skipped; if the first non-white space character after 230 * the key is <code>'='</code> or <code>':'</code>, then it is 231 * ignored and any white space characters after it are also 232 * skipped. All remaining characters on the line become part of 233 * the associated element string; if there are no remaining 234 * characters, the element is the empty string 235 * <code>""</code>. Once the raw character sequences 236 * constituting the key and element are identified, escape 237 * processing is performed as described above. 238 * 239 * <p> 240 * As an example, each of the following three lines specifies the key 241 * <code>"Truth"</code> and the associated element value 242 * <code>"Beauty"</code>: 243 * <p> 244 * <pre> 245 * Truth = Beauty 246 * Truth:Beauty 247 * Truth :Beauty 248 * </pre> 249 * As another example, the following three lines specify a single 250 * property: 251 * <p> 252 * <pre> 253 * fruits apple, banana, pear, \ 254 * cantaloupe, watermelon, \ 255 * kiwi, mango 256 * </pre> 257 * The key is <code>"fruits"</code> and the associated element is: 258 * <p> 259 * <pre>"apple, banana, pear, cantaloupe, watermelon, kiwi, mango"</pre> 260 * Note that a space appears before each <code>\</code> so that a space 261 * will appear after each comma in the final result; the <code>\</code>, 262 * line terminator, and leading white space on the continuation line are 263 * merely discarded and are <i>not</i> replaced by one or more other 264 * characters. 265 * <p> 266 * As a third example, the line: 267 * <p> 268 * <pre>cheeses 269 * </pre> 270 * specifies that the key is <code>"cheeses"</code> and the associated 271 * element is the empty string <code>""</code>.<p> 272 * <p> 273 * 274 * <a name="unicodeescapes"></a> 275 * Characters in keys and elements can be represented in escape 276 * sequences similar to those used for character and string literals 277 * (see sections 3.3 and 3.10.6 of 278 * <cite>The Java™ Language Specification</cite>). 279 * 280 * The differences from the character escape sequences and Unicode 281 * escapes used for characters and strings are: 282 * 283 * <ul> 284 * <li> Octal escapes are not recognized. 285 * 286 * <li> The character sequence <code>\b</code> does <i>not</i> 287 * represent a backspace character. 288 * 289 * <li> The method does not treat a backslash character, 290 * <code>\</code>, before a non-valid escape character as an 291 * error; the backslash is silently dropped. For example, in a 292 * Java string the sequence <code>"\z"</code> would cause a 293 * compile time error. In contrast, this method silently drops 294 * the backslash. Therefore, this method treats the two character 295 * sequence <code>"\b"</code> as equivalent to the single 296 * character <code>'b'</code>. 297 * 298 * <li> Escapes are not necessary for single and double quotes; 299 * however, by the rule above, single and double quote characters 300 * preceded by a backslash still yield single and double quote 301 * characters, respectively. 302 * 303 * <li> Only a single 'u' character is allowed in a Uniocde escape 304 * sequence. 305 * 306 * </ul> 307 * <p> 308 * The specified stream remains open after this method returns. 309 * 310 * @param reader the input character stream. 311 * @throws IOException if an error occurred when reading from the 312 * input stream. 313 * @throws IllegalArgumentException if a malformed Unicode escape 314 * appears in the input. 315 * @since 1.6 316 */ 317 public synchronized void load(Reader reader) throws IOException { 318 load0(new LineReader(reader)); 319 } 320 321 /** 322 * Reads a property list (key and element pairs) from the input 323 * byte stream. The input stream is in a simple line-oriented 324 * format as specified in 325 * {@link #load(java.io.Reader) load(Reader)} and is assumed to use 326 * the ISO 8859-1 character encoding; that is each byte is one Latin1 327 * character. Characters not in Latin1, and certain special characters, 328 * are represented in keys and elements using Unicode escapes as defined in 329 * section 3.3 of 330 * <cite>The Java™ Language Specification</cite>. 331 * <p> 332 * The specified stream remains open after this method returns. 333 * 334 * @param inStream the input stream. 335 * @exception IOException if an error occurred when reading from the 336 * input stream. 337 * @throws IllegalArgumentException if the input stream contains a 338 * malformed Unicode escape sequence. 339 * @since 1.2 340 */ 341 public synchronized void load(InputStream inStream) throws IOException { 342 load0(new LineReader(inStream)); 343 } 344 345 private void load0 (LineReader lr) throws IOException { 346 char[] convtBuf = new char[1024]; 347 int limit; 348 int keyLen; 349 int valueStart; 350 char c; 351 boolean hasSep; 352 boolean precedingBackslash; 353 354 while ((limit = lr.readLine()) >= 0) { 355 c = 0; 356 keyLen = 0; 357 valueStart = limit; 358 hasSep = false; 359 360 //System.out.println("line=<" + new String(lineBuf, 0, limit) + ">"); 361 precedingBackslash = false; 362 while (keyLen < limit) { 363 c = lr.lineBuf[keyLen]; 364 //need check if escaped. 365 if ((c == '=' || c == ':') && !precedingBackslash) { 366 valueStart = keyLen + 1; 367 hasSep = true; 368 break; 369 } else if (Character.isWhitespace(c) && !precedingBackslash) { 370 valueStart = keyLen + 1; 371 break; 372 } 373 if (c == '\\') { 374 precedingBackslash = !precedingBackslash; 375 } else { 376 precedingBackslash = false; 377 } 378 keyLen++; 379 } 380 while (valueStart < limit) { 381 c = lr.lineBuf[valueStart]; 382 if (!Character.isWhitespace(c)) { 383 if (!hasSep && (c == '=' || c == ':')) { 384 hasSep = true; 385 } else { 386 break; 387 } 388 } 389 valueStart++; 390 } 391 String key = loadConvert(lr.lineBuf, 0, keyLen, convtBuf); 392 String value = loadConvert(lr.lineBuf, valueStart, limit - valueStart, convtBuf); 393 put(key, value); 394 } 395 } 396 397 /* Read in a "logical line" from an InputStream/Reader, skip all comment 398 * and blank lines and filter out those leading whitespace characters 399 * (\u0020, \u0009 and \u000c) from the beginning of a "natural line". 400 * Method returns the char length of the "logical line" and stores 401 * the line in "lineBuf". 402 */ 403 class LineReader { 404 public LineReader(InputStream inStream) { 405 this.inStream = inStream; 406 inByteBuf = new byte[8192]; 407 } 408 409 public LineReader(Reader reader) { 410 this.reader = reader; 411 inCharBuf = new char[8192]; 412 } 413 414 byte[] inByteBuf; 415 char[] inCharBuf; 416 char[] lineBuf = new char[1024]; 417 int inLimit = 0; 418 int inOff = 0; 419 InputStream inStream; 420 Reader reader; 421 422 int readLine() throws IOException { 423 int len = 0; 424 char c = 0; 425 426 boolean skipWhiteSpace = true; 427 boolean isCommentLine = false; 428 boolean isNewLine = true; 429 boolean appendedLineBegin = false; 430 boolean precedingBackslash = false; 431 boolean skipLF = false; 432 433 while (true) { 434 if (inOff >= inLimit) { 435 inLimit = (inStream==null)?reader.read(inCharBuf) 436 :inStream.read(inByteBuf); 437 inOff = 0; 438 if (inLimit <= 0) { 439 if (len == 0 || isCommentLine) { 440 return -1; 441 } 442 return len; 443 } 444 } 445 if (inStream != null) { 446 //The line below is equivalent to calling a 447 //ISO8859-1 decoder. 448 c = (char) (0xff & inByteBuf[inOff++]); 449 } else { 450 c = inCharBuf[inOff++]; 451 } 452 if (skipLF) { 453 skipLF = false; 454 if (c == '\n') { 455 continue; 456 } 457 } 458 if (skipWhiteSpace) { 459 if (Character.isWhitespace(c)) { 460 continue; 461 } 462 if (!appendedLineBegin && (c == '\r' || c == '\n')) { 463 continue; 464 } 465 skipWhiteSpace = false; 466 appendedLineBegin = false; 467 } 468 if (isNewLine) { 469 isNewLine = false; 470 if (c == '#' || c == '!') { 471 isCommentLine = true; 472 continue; 473 } 474 } 475 476 if (c != '\n' && c != '\r') { 477 lineBuf[len++] = c; 478 if (len == lineBuf.length) { 479 int newLength = lineBuf.length * 2; 480 if (newLength < 0) { 481 newLength = Integer.MAX_VALUE; 482 } 483 char[] buf = new char[newLength]; 484 System.arraycopy(lineBuf, 0, buf, 0, lineBuf.length); 485 lineBuf = buf; 486 } 487 //flip the preceding backslash flag 488 if (c == '\\') { 489 precedingBackslash = !precedingBackslash; 490 } else { 491 precedingBackslash = false; 492 } 493 } 494 else { 495 // reached EOL 496 if (isCommentLine || len == 0) { 497 isCommentLine = false; 498 isNewLine = true; 499 skipWhiteSpace = true; 500 len = 0; 501 continue; 502 } 503 if (inOff >= inLimit) { 504 inLimit = (inStream==null) 505 ?reader.read(inCharBuf) 506 :inStream.read(inByteBuf); 507 inOff = 0; 508 if (inLimit <= 0) { 509 return len; 510 } 511 } 512 if (precedingBackslash) { 513 len -= 1; 514 //skip the leading whitespace characters in following line 515 skipWhiteSpace = true; 516 appendedLineBegin = true; 517 precedingBackslash = false; 518 if (c == '\r') { 519 skipLF = true; 520 } 521 } else { 522 return len; 523 } 524 } 525 } 526 } 527 } 528 529 /* 530 * Converts encoded \uxxxx to unicode chars 531 * and changes special saved chars to their original forms 532 */ 533 private String loadConvert (char[] in, int off, int len, char[] convtBuf) { 534 if (convtBuf.length < len) { 535 int newLen = len * 2; 536 if (newLen < 0) { 537 newLen = Integer.MAX_VALUE; 538 } 539 convtBuf = new char[newLen]; 540 } 541 char aChar; 542 char[] out = convtBuf; 543 int outLen = 0; 544 int end = off + len; 545 546 while (off < end) { 547 aChar = in[off++]; 548 if (aChar == '\\') { 549 aChar = in[off++]; 550 if(aChar == 'u') { 551 // Read the xxxx 552 int value=0; 553 for (int i=0; i<4; i++) { 554 aChar = in[off++]; 555 switch (aChar) { 556 case '0': case '1': case '2': case '3': case '4': 557 case '5': case '6': case '7': case '8': case '9': 558 value = (value << 4) + aChar - '0'; 559 break; 560 case 'a': case 'b': case 'c': 561 case 'd': case 'e': case 'f': 562 value = (value << 4) + 10 + aChar - 'a'; 563 break; 564 case 'A': case 'B': case 'C': 565 case 'D': case 'E': case 'F': 566 value = (value << 4) + 10 + aChar - 'A'; 567 break; 568 default: 569 throw new IllegalArgumentException( 570 "Malformed \\uxxxx encoding."); 571 } 572 } 573 out[outLen++] = (char)value; 574 } else { 575 if (aChar == 't') aChar = '\t'; 576 else if (aChar == 'r') aChar = '\r'; 577 else if (aChar == 'n') aChar = '\n'; 578 else if (aChar == 'f') aChar = '\f'; 579 out[outLen++] = aChar; 580 } 581 } else { 582 out[outLen++] = aChar; 583 } 584 } 585 return new String (out, 0, outLen); 586 } 587 588 /* 589 * Converts unicodes to encoded \uxxxx and escapes 590 * special characters with a preceding slash 591 */ 592 private String saveConvert(String theString, 593 boolean escapeSpace, 594 boolean escapeUnicode) { 595 int len = theString.length(); 596 int bufLen = len * 2; 597 if (bufLen < 0) { 598 bufLen = Integer.MAX_VALUE; 599 } 600 StringBuffer outBuffer = new StringBuffer(bufLen); 601 602 for(int x=0; x<len; x++) { 603 char aChar = theString.charAt(x); 604 // Handle common case first, selecting largest block that 605 // avoids the specials below 606 if ((aChar > 61) && (aChar < 127)) { 607 if (aChar == '\\') { 608 outBuffer.append('\\'); outBuffer.append('\\'); 609 continue; 610 } 611 outBuffer.append(aChar); 612 continue; 613 } 614 switch(aChar) { 615 case ' ': 616 if (x == 0 || escapeSpace) 617 outBuffer.append('\\'); 618 outBuffer.append(' '); 619 break; 620 case '\t':outBuffer.append('\\'); outBuffer.append('t'); 621 break; 622 case '\n':outBuffer.append('\\'); outBuffer.append('n'); 623 break; 624 case '\r':outBuffer.append('\\'); outBuffer.append('r'); 625 break; 626 case '\f':outBuffer.append('\\'); outBuffer.append('f'); 627 break; 628 case '=': // Fall through 629 case ':': // Fall through 630 case '#': // Fall through 631 case '!': 632 outBuffer.append('\\'); outBuffer.append(aChar); 633 break; 634 default: 635 if (((aChar < 0x0020) || (aChar > 0x007e)) & escapeUnicode ) { 636 outBuffer.append('\\'); 637 outBuffer.append('u'); 638 outBuffer.append(toHex((aChar >> 12) & 0xF)); 639 outBuffer.append(toHex((aChar >> 8) & 0xF)); 640 outBuffer.append(toHex((aChar >> 4) & 0xF)); 641 outBuffer.append(toHex( aChar & 0xF)); 642 } else { 643 outBuffer.append(aChar); 644 } 645 } 646 } 647 return outBuffer.toString(); 648 } 649 650 private static void writeComments(BufferedWriter bw, String comments) 651 throws IOException { 652 bw.write("#"); 653 int len = comments.length(); 654 int current = 0; 655 int last = 0; 656 char[] uu = new char[6]; 657 uu[0] = '\\'; 658 uu[1] = 'u'; 659 while (current < len) { 660 char c = comments.charAt(current); 661 if (c > '\u00ff' || c == '\n' || c == '\r') { 662 if (last != current) 663 bw.write(comments.substring(last, current)); 664 if (c > '\u00ff') { 665 uu[2] = toHex((c >> 12) & 0xf); 666 uu[3] = toHex((c >> 8) & 0xf); 667 uu[4] = toHex((c >> 4) & 0xf); 668 uu[5] = toHex( c & 0xf); 669 bw.write(new String(uu)); 670 } else { 671 bw.newLine(); 672 if (c == '\r' && 673 current != len - 1 && 674 comments.charAt(current + 1) == '\n') { 675 current++; 676 } 677 if (current == len - 1 || 678 (comments.charAt(current + 1) != '#' && 679 comments.charAt(current + 1) != '!')) 680 bw.write("#"); 681 } 682 last = current + 1; 683 } 684 current++; 685 } 686 if (last != current) 687 bw.write(comments.substring(last, current)); 688 bw.newLine(); 689 } 690 691 /** 692 * Calls the <code>store(OutputStream out, String comments)</code> method 693 * and suppresses IOExceptions that were thrown. 694 * 695 * @deprecated This method does not throw an IOException if an I/O error 696 * occurs while saving the property list. The preferred way to save a 697 * properties list is via the <code>store(OutputStream out, 698 * String comments)</code> method or the 699 * <code>storeToXML(OutputStream os, String comment)</code> method. 700 * 701 * @param out an output stream. 702 * @param comments a description of the property list. 703 * @exception ClassCastException if this <code>Properties</code> object 704 * contains any keys or values that are not 705 * <code>Strings</code>. 706 */ 707 @Deprecated 708 public void save(OutputStream out, String comments) { 709 try { 710 store(out, comments); 711 } catch (IOException e) { 712 } 713 } 714 715 /** 716 * Writes this property list (key and element pairs) in this 717 * <code>Properties</code> table to the output character stream in a 718 * format suitable for using the {@link #load(java.io.Reader) load(Reader)} 719 * method. 720 * <p> 721 * Properties from the defaults table of this <code>Properties</code> 722 * table (if any) are <i>not</i> written out by this method. 723 * <p> 724 * If the comments argument is not null, then an ASCII <code>#</code> 725 * character, the comments string, and a line separator are first written 726 * to the output stream. Thus, the <code>comments</code> can serve as an 727 * identifying comment. Any one of a line feed ('\n'), a carriage 728 * return ('\r'), or a carriage return followed immediately by a line feed 729 * in comments is replaced by a line separator generated by the <code>Writer</code> 730 * and if the next character in comments is not character <code>#</code> or 731 * character <code>!</code> then an ASCII <code>#</code> is written out 732 * after that line separator. 733 * <p> 734 * Next, a comment line is always written, consisting of an ASCII 735 * <code>#</code> character, the current date and time (as if produced 736 * by the <code>toString</code> method of <code>Date</code> for the 737 * current time), and a line separator as generated by the <code>Writer</code>. 738 * <p> 739 * Then every entry in this <code>Properties</code> table is 740 * written out, one per line. For each entry the key string is 741 * written, then an ASCII <code>=</code>, then the associated 742 * element string. For the key, all space characters are 743 * written with a preceding <code>\</code> character. For the 744 * element, leading space characters, but not embedded or trailing 745 * space characters, are written with a preceding <code>\</code> 746 * character. The key and element characters <code>#</code>, 747 * <code>!</code>, <code>=</code>, and <code>:</code> are written 748 * with a preceding backslash to ensure that they are properly loaded. 749 * <p> 750 * After the entries have been written, the output stream is flushed. 751 * The output stream remains open after this method returns. 752 * <p> 753 * 754 * @param writer an output character stream writer. 755 * @param comments a description of the property list. 756 * @exception IOException if writing this property list to the specified 757 * output stream throws an <tt>IOException</tt>. 758 * @exception ClassCastException if this <code>Properties</code> object 759 * contains any keys or values that are not <code>Strings</code>. 760 * @exception NullPointerException if <code>writer</code> is null. 761 * @since 1.6 762 */ 763 public void store(Writer writer, String comments) 764 throws IOException 765 { 766 store0((writer instanceof BufferedWriter)?(BufferedWriter)writer 767 : new BufferedWriter(writer), 768 comments, 769 false); 770 } 771 772 /** 773 * Writes this property list (key and element pairs) in this 774 * <code>Properties</code> table to the output stream in a format suitable 775 * for loading into a <code>Properties</code> table using the 776 * {@link #load(InputStream) load(InputStream)} method. 777 * <p> 778 * Properties from the defaults table of this <code>Properties</code> 779 * table (if any) are <i>not</i> written out by this method. 780 * <p> 781 * This method outputs the comments, properties keys and values in 782 * the same format as specified in 783 * {@link #store(java.io.Writer, java.lang.String) store(Writer)}, 784 * with the following differences: 785 * <ul> 786 * <li>The stream is written using the ISO 8859-1 character encoding. 787 * 788 * <li>Characters not in Latin-1 in the comments are written as 789 * <code>\u</code><i>xxxx</i> for their appropriate unicode 790 * hexadecimal value <i>xxxx</i>. 791 * 792 * <li>Characters less than <code>\u0020</code> and characters greater 793 * than <code>\u007E</code> in property keys or values are written 794 * as <code>\u</code><i>xxxx</i> for the appropriate hexadecimal 795 * value <i>xxxx</i>. 796 * </ul> 797 * <p> 798 * After the entries have been written, the output stream is flushed. 799 * The output stream remains open after this method returns. 800 * <p> 801 * @param out an output stream. 802 * @param comments a description of the property list. 803 * @exception IOException if writing this property list to the specified 804 * output stream throws an <tt>IOException</tt>. 805 * @exception ClassCastException if this <code>Properties</code> object 806 * contains any keys or values that are not <code>Strings</code>. 807 * @exception NullPointerException if <code>out</code> is null. 808 * @since 1.2 809 */ 810 public void store(OutputStream out, String comments) 811 throws IOException 812 { 813 store0(new BufferedWriter(new OutputStreamWriter(out, "8859_1")), 814 comments, 815 true); 816 } 817 818 private void store0(BufferedWriter bw, String comments, boolean escUnicode) 819 throws IOException 820 { 821 if (comments != null) { 822 writeComments(bw, comments); 823 } 824 bw.write("#" + new Date().toString()); 825 bw.newLine(); 826 synchronized (this) { 827 for (Enumeration e = keys(); e.hasMoreElements();) { 828 String key = (String)e.nextElement(); 829 String val = (String)get(key); 830 key = saveConvert(key, true, escUnicode); 831 /* No need to escape embedded and trailing spaces for value, hence 832 * pass false to flag. 833 */ 834 val = saveConvert(val, false, escUnicode); 835 bw.write(key + "=" + val); 836 bw.newLine(); 837 } 838 } 839 bw.flush(); 840 } 841 842 /** 843 * Loads all of the properties represented by the XML document on the 844 * specified input stream into this properties table. 845 * 846 * <p>The XML document must have the following DOCTYPE declaration: 847 * <pre> 848 * <!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd"> 849 * </pre> 850 * Furthermore, the document must satisfy the properties DTD described 851 * above. 852 * 853 * <p>The specified stream is closed after this method returns. 854 * 855 * @param in the input stream from which to read the XML document. 856 * @throws IOException if reading from the specified input stream 857 * results in an <tt>IOException</tt>. 858 * @throws InvalidPropertiesFormatException Data on input stream does not 859 * constitute a valid XML document with the mandated document type. 860 * @throws NullPointerException if <code>in</code> is null. 861 * @see #storeToXML(OutputStream, String, String) 862 * @since 1.5 863 */ 864 public synchronized void loadFromXML(InputStream in) 865 throws IOException, InvalidPropertiesFormatException 866 { 867 if (in == null) 868 throw new NullPointerException(); 869 XMLUtils.load(this, in); 870 in.close(); 871 } 872 873 /** 874 * Emits an XML document representing all of the properties contained 875 * in this table. 876 * 877 * <p> An invocation of this method of the form <tt>props.storeToXML(os, 878 * comment)</tt> behaves in exactly the same way as the invocation 879 * <tt>props.storeToXML(os, comment, "UTF-8");</tt>. 880 * 881 * @param os the output stream on which to emit the XML document. 882 * @param comment a description of the property list, or <code>null</code> 883 * if no comment is desired. 884 * @throws IOException if writing to the specified output stream 885 * results in an <tt>IOException</tt>. 886 * @throws NullPointerException if <code>os</code> is null. 887 * @throws ClassCastException if this <code>Properties</code> object 888 * contains any keys or values that are not 889 * <code>Strings</code>. 890 * @see #loadFromXML(InputStream) 891 * @since 1.5 892 */ 893 public void storeToXML(OutputStream os, String comment) 894 throws IOException 895 { 896 if (os == null) 897 throw new NullPointerException(); 898 storeToXML(os, comment, "UTF-8"); 899 } 900 901 /** 902 * Emits an XML document representing all of the properties contained 903 * in this table, using the specified encoding. 904 * 905 * <p>The XML document will have the following DOCTYPE declaration: 906 * <pre> 907 * <!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd"> 908 * </pre> 909 * 910 *<p>If the specified comment is <code>null</code> then no comment 911 * will be stored in the document. 912 * 913 * <p>The specified stream remains open after this method returns. 914 * 915 * @param os the output stream on which to emit the XML document. 916 * @param comment a description of the property list, or <code>null</code> 917 * if no comment is desired. 918 * @param encoding the name of a supported 919 * <a href="../lang/package-summary.html#charenc"> 920 * character encoding</a> 921 * 922 * @throws IOException if writing to the specified output stream 923 * results in an <tt>IOException</tt>. 924 * @throws NullPointerException if <code>os</code> is <code>null</code>, 925 * or if <code>encoding</code> is <code>null</code>. 926 * @throws ClassCastException if this <code>Properties</code> object 927 * contains any keys or values that are not 928 * <code>Strings</code>. 929 * @see #loadFromXML(InputStream) 930 * @since 1.5 931 */ 932 public void storeToXML(OutputStream os, String comment, String encoding) 933 throws IOException 934 { 935 if (os == null) 936 throw new NullPointerException(); 937 XMLUtils.save(this, os, comment, encoding); 938 } 939 940 /** 941 * Searches for the property with the specified key in this property list. 942 * If the key is not found in this property list, the default property list, 943 * and its defaults, recursively, are then checked. The method returns 944 * <code>null</code> if the property is not found. 945 * 946 * @param key the property key. 947 * @return the value in this property list with the specified key value. 948 * @see #setProperty 949 * @see #defaults 950 */ 951 public String getProperty(String key) { 952 Object oval = super.get(key); 953 String sval = (oval instanceof String) ? (String)oval : null; 954 return ((sval == null) && (defaults != null)) ? defaults.getProperty(key) : sval; 955 } 956 957 /** 958 * Searches for the property with the specified key in this property list. 959 * If the key is not found in this property list, the default property list, 960 * and its defaults, recursively, are then checked. The method returns the 961 * default value argument if the property is not found. 962 * 963 * @param key the hashtable key. 964 * @param defaultValue a default value. 965 * 966 * @return the value in this property list with the specified key value. 967 * @see #setProperty 968 * @see #defaults 969 */ 970 public String getProperty(String key, String defaultValue) { 971 String val = getProperty(key); 972 return (val == null) ? defaultValue : val; 973 } 974 975 /** 976 * Returns an enumeration of all the keys in this property list, 977 * including distinct keys in the default property list if a key 978 * of the same name has not already been found from the main 979 * properties list. 980 * 981 * @return an enumeration of all the keys in this property list, including 982 * the keys in the default property list. 983 * @throws ClassCastException if any key in this property list 984 * is not a string. 985 * @see java.util.Enumeration 986 * @see java.util.Properties#defaults 987 * @see #stringPropertyNames 988 */ 989 public Enumeration<?> propertyNames() { 990 Hashtable h = new Hashtable(); 991 enumerate(h); 992 return h.keys(); 993 } 994 995 /** 996 * Returns a set of keys in this property list where 997 * the key and its corresponding value are strings, 998 * including distinct keys in the default property list if a key 999 * of the same name has not already been found from the main 1000 * properties list. Properties whose key or value is not 1001 * of type <tt>String</tt> are omitted. 1002 * <p> 1003 * The returned set is not backed by the <tt>Properties</tt> object. 1004 * Changes to this <tt>Properties</tt> are not reflected in the set, 1005 * or vice versa. 1006 * 1007 * @return a set of keys in this property list where 1008 * the key and its corresponding value are strings, 1009 * including the keys in the default property list. 1010 * @see java.util.Properties#defaults 1011 * @since 1.6 1012 */ 1013 public Set<String> stringPropertyNames() { 1014 Hashtable<String, String> h = new Hashtable<>(); 1015 enumerateStringProperties(h); 1016 return h.keySet(); 1017 } 1018 1019 /** 1020 * Prints this property list out to the specified output stream. 1021 * This method is useful for debugging. 1022 * 1023 * @param out an output stream. 1024 * @throws ClassCastException if any key in this property list 1025 * is not a string. 1026 */ 1027 public void list(PrintStream out) { 1028 out.println("-- listing properties --"); 1029 Hashtable h = new Hashtable(); 1030 enumerate(h); 1031 for (Enumeration e = h.keys() ; e.hasMoreElements() ;) { 1032 String key = (String)e.nextElement(); 1033 String val = (String)h.get(key); 1034 if (val.length() > 40) { 1035 val = val.substring(0, 37) + "..."; 1036 } 1037 out.println(key + "=" + val); 1038 } 1039 } 1040 1041 /** 1042 * Prints this property list out to the specified output stream. 1043 * This method is useful for debugging. 1044 * 1045 * @param out an output stream. 1046 * @throws ClassCastException if any key in this property list 1047 * is not a string. 1048 * @since JDK1.1 1049 */ 1050 /* 1051 * Rather than use an anonymous inner class to share common code, this 1052 * method is duplicated in order to ensure that a non-1.1 compiler can 1053 * compile this file. 1054 */ 1055 public void list(PrintWriter out) { 1056 out.println("-- listing properties --"); 1057 Hashtable h = new Hashtable(); 1058 enumerate(h); 1059 for (Enumeration e = h.keys() ; e.hasMoreElements() ;) { 1060 String key = (String)e.nextElement(); 1061 String val = (String)h.get(key); 1062 if (val.length() > 40) { 1063 val = val.substring(0, 37) + "..."; 1064 } 1065 out.println(key + "=" + val); 1066 } 1067 } 1068 1069 /** 1070 * Enumerates all key/value pairs in the specified hashtable. 1071 * @param h the hashtable 1072 * @throws ClassCastException if any of the property keys 1073 * is not of String type. 1074 */ 1075 private synchronized void enumerate(Hashtable h) { 1076 if (defaults != null) { 1077 defaults.enumerate(h); 1078 } 1079 for (Enumeration e = keys() ; e.hasMoreElements() ;) { 1080 String key = (String)e.nextElement(); 1081 h.put(key, get(key)); 1082 } 1083 } 1084 1085 /** 1086 * Enumerates all key/value pairs in the specified hashtable 1087 * and omits the property if the key or value is not a string. 1088 * @param h the hashtable 1089 */ 1090 private synchronized void enumerateStringProperties(Hashtable<String, String> h) { 1091 if (defaults != null) { 1092 defaults.enumerateStringProperties(h); 1093 } 1094 for (Enumeration e = keys() ; e.hasMoreElements() ;) { 1095 Object k = e.nextElement(); 1096 Object v = get(k); 1097 if (k instanceof String && v instanceof String) { 1098 h.put((String) k, (String) v); 1099 } 1100 } 1101 } 1102 1103 /** 1104 * Convert a nibble to a hex character 1105 * @param nibble the nibble to convert. 1106 */ 1107 private static char toHex(int nibble) { 1108 return hexDigit[(nibble & 0xF)]; 1109 } 1110 1111 /** A table of hex digits */ 1112 private static final char[] hexDigit = { 1113 '0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F' 1114 }; 1115} 1116