libjava/classpath/gnu/javax/net/ssl/provider/Util.java

   1 /* Util.java -- Miscellaneous utility methods.
   2    Copyright (C) 2006  Free Software Foundation, Inc.
   3
   4 This file is a part of GNU Classpath.
   5
   6 GNU Classpath is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2 of the License, or (at
   9 your option) any later version.
  10
  11 GNU Classpath is distributed in the hope that it will be useful, but
  12 WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU Classpath; if not, write to the Free Software
  18 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301
  19 USA
  20
  21 Linking this library statically or dynamically with other modules is
  22 making a combined work based on this library.  Thus, the terms and
  23 conditions of the GNU General Public License cover the whole
  24 combination.
  25
  26 As a special exception, the copyright holders of this library give you
  27 permission to link this library with independent modules to produce an
  28 executable, regardless of the license terms of these independent
  29 modules, and to copy and distribute the resulting executable under
  30 terms of your choice, provided that you also meet, for each linked
  31 independent module, the terms and conditions of the license of that
  32 module.  An independent module is a module which is not derived from
  33 or based on this library.  If you modify this library, you may extend
  34 this exception to your version of the library, but you are not
  35 obligated to do so.  If you do not wish to do so, delete this
  36 exception statement from your version.  */
  37
  38
  39 package gnu.javax.net.ssl.provider;
  40
  41 import gnu.java.lang.CPStringBuilder;
  42
  43 import java.io.PrintWriter;
  44 import java.io.StringWriter;
  45
  46 import java.lang.reflect.Array;
  47 import java.lang.reflect.InvocationTargetException;
  48 import java.lang.reflect.Method;
  49 import java.math.BigInteger;
  50
  51 import java.nio.ByteBuffer;
  52
  53 import java.security.AccessController;
  54 import java.security.PrivilegedAction;
  55 import java.security.Security;
  56
  57 /**
  58  * A collection of useful class methods.
  59  *
  60  * @author Casey Marshall (rsdio@metastatic.org)
  61  */
  62 public final class Util
  63 {
  64
  65   // Constants.
  66   // -------------------------------------------------------------------------
  67
  68   static final String HEX = "0123456789abcdef";
  69
  70   // Static methods only.
  71   private Util() { }
  72
  73   // Class methods.
  74   // -------------------------------------------------------------------------
  75
  76   public static Object wrapBuffer(ByteBuffer buffer)
  77   {
  78     return wrapBuffer(buffer, "");
  79   }
  80
  81   public static Object wrapBuffer(ByteBuffer buffer, String prefix)
  82   {
  83     return new WrappedBuffer(buffer, prefix);
  84   }
  85
  86   private static class WrappedBuffer
  87   {
  88     private final ByteBuffer buffer;
  89     private final String prefix;
  90
  91     WrappedBuffer(ByteBuffer buffer, String prefix)
  92     {
  93       this.buffer = buffer;
  94       this.prefix = prefix;
  95     }
  96
  97     public String toString()
  98     {
  99       return hexDump(buffer, prefix);
 100     }
 101   }
 102
 103   /**
 104    * Convert a hexadecimal string into its byte representation.
 105    *
 106    * @param hex The hexadecimal string.
 107    * @return The converted bytes.
 108    */
 109   public static byte[] toByteArray(String hex)
 110   {
 111     hex = hex.toLowerCase();
 112     byte[] buf = new byte[hex.length() / 2];
 113     int j = 0;
 114     for (int i = 0; i < buf.length; i++)
 115       {
 116         buf[i] = (byte) ((Character.digit(hex.charAt(j++), 16) << 4) |
 117                           Character.digit(hex.charAt(j++), 16));
 118       }
 119     return buf;
 120   }
 121
 122   /**
 123    * Convert a byte array to a hexadecimal string, as though it were a
 124    * big-endian arbitrarily-sized integer.
 125    *
 126    * @param buf The bytes to format.
 127    * @param off The offset to start at.
 128    * @param len The number of bytes to format.
 129    * @return A hexadecimal representation of the specified bytes.
 130    */
 131   public static String toHexString(byte[] buf, int off, int len)
 132   {
 133     CPStringBuilder str = new CPStringBuilder();
 134     for (int i = 0; i < len; i++)
 135       {
 136         str.append(HEX.charAt(buf[i+off] >>> 4 & 0x0F));
 137         str.append(HEX.charAt(buf[i+off] & 0x0F));
 138       }
 139     return str.toString();
 140   }
 141
 142   /**
 143    * See {@link #toHexString(byte[],int,int)}.
 144    */
 145   public static String toHexString(byte[] buf)
 146   {
 147     return Util.toHexString(buf, 0, buf.length);
 148   }
 149
 150   /**
 151    * Convert a byte array to a hexadecimal string, separating octets
 152    * with the given character.
 153    *
 154    * @param buf The bytes to format.
 155    * @param off The offset to start at.
 156    * @param len The number of bytes to format.
 157    * @param sep The character to insert between octets.
 158    * @return A hexadecimal representation of the specified bytes.
 159    */
 160   public static String toHexString(byte[] buf, int off, int len, char sep)
 161   {
 162     CPStringBuilder str = new CPStringBuilder();
 163     for (int i = 0; i < len; i++)
 164       {
 165         str.append(HEX.charAt(buf[i+off] >>> 4 & 0x0F));
 166         str.append(HEX.charAt(buf[i+off] & 0x0F));
 167         if (i < len - 1)
 168           str.append(sep);
 169       }
 170     return str.toString();
 171   }
 172
 173   /**
 174    * See {@link #toHexString(byte[],int,int,char)}.
 175    */
 176   public static String toHexString(byte[] buf, char sep)
 177   {
 178     return Util.toHexString(buf, 0, buf.length, sep);
 179   }
 180
 181   /**
 182    * Create a representation of the given byte array similar to the
 183    * output of <code>`hexdump -C'</code>, which is
 184    *
 185    * <p><pre>OFFSET  SIXTEEN-BYTES-IN-HEX  PRINTABLE-BYTES</pre>
 186    *
 187    * <p>The printable bytes show up as-is if they are printable and
 188    * not a newline character, otherwise showing as '.'.
 189    *
 190    * @param buf The bytes to format.
 191    * @param off The offset to start at.
 192    * @param len The number of bytes to encode.
 193    * @param prefix A string to prepend to every line.
 194    * @return The formatted string.
 195    */
 196   public static String hexDump(byte[] buf, int off, int len, String prefix)
 197   {
 198     String nl = getProperty("line.separator");
 199     CPStringBuilder str = new CPStringBuilder();
 200     int i = 0;
 201     while (i < len)
 202       {
 203         if (prefix != null)
 204           str.append(prefix);
 205         str.append(Util.formatInt(i+off, 16, 8));
 206         str.append("  ");
 207         String s = Util.toHexString(buf, i+off, Math.min(16, len-i), ' ');
 208         str.append(s);
 209         for (int j = s.length(); j < 49; j++)
 210           str.append(" ");
 211         for (int j = 0; j < Math.min(16, len - i); j++)
 212           {
 213             if ((buf[i+off+j] & 0xFF) < 0x20 || (buf[i+off+j] & 0xFF) > 0x7E)
 214               str.append('.');
 215             else
 216               str.append((char) (buf[i+off+j] & 0xFF));
 217           }
 218         str.append(nl);
 219         i += 16;
 220       }
 221     return str.toString();
 222   }
 223
 224   public static String hexDump (ByteBuffer buf)
 225   {
 226     return hexDump (buf, null);
 227   }
 228
 229   public static String hexDump (ByteBuffer buf, String prefix)
 230   {
 231     buf = buf.duplicate();
 232     StringWriter str = new StringWriter ();
 233     PrintWriter out = new PrintWriter (str);
 234     int i = 0;
 235     int len = buf.remaining();
 236     byte[] line = new byte[16];
 237     while (i < len)
 238       {
 239         if (prefix != null)
 240           out.print(prefix);
 241         out.print(Util.formatInt (i, 16, 8));
 242         out.print("  ");
 243         int l = Math.min(16, len - i);
 244         buf.get(line, 0, l);
 245         String s = Util.toHexString(line, 0, l, ' ');
 246         out.print(s);
 247         for (int j = s.length(); j < 49; j++)
 248           out.print(' ');
 249         for (int j = 0; j < l; j++)
 250           {
 251             int c = line[j] & 0xFF;
 252             if (c < 0x20 || c > 0x7E)
 253               out.print('.');
 254             else
 255               out.print((char) c);
 256           }
 257         out.println();
 258         i += 16;
 259       }
 260     return str.toString();
 261   }
 262
 263   /**
 264    * See {@link #hexDump(byte[],int,int,String)}.
 265    */
 266   public static String hexDump(byte[] buf, int off, int len)
 267   {
 268     return hexDump(buf, off, len, "");
 269   }
 270
 271   /**
 272    * See {@link #hexDump(byte[],int,int,String)}.
 273    */
 274   public static String hexDump(byte[] buf, String prefix)
 275   {
 276     return hexDump(buf, 0, buf.length, prefix);
 277   }
 278
 279   /**
 280    * See {@link #hexDump(byte[],int,int,String)}.
 281    */
 282   public static String hexDump(byte[] buf)
 283   {
 284     return hexDump(buf, 0, buf.length);
 285   }
 286
 287   /**
 288    * Format an integer into the specified radix, zero-filled.
 289    *
 290    * @param i The integer to format.
 291    * @param radix The radix to encode to.
 292    * @param len The target length of the string. The string is
 293    *   zero-padded to this length, but may be longer.
 294    * @return The formatted integer.
 295    */
 296   public static String formatInt(int i, int radix, int len)
 297   {
 298     String s = Integer.toString(i, radix);
 299     CPStringBuilder buf = new CPStringBuilder();
 300     for (int j = 0; j < len - s.length(); j++)
 301       buf.append("0");
 302     buf.append(s);
 303     return buf.toString();
 304   }
 305
 306   /**
 307    * Concatenate two byte arrays into one.
 308    *
 309    * @param b1 The first byte array.
 310    * @param b2 The second byte array.
 311    * @return The concatenation of b1 and b2.
 312    */
 313   public static byte[] concat(byte[] b1, byte[] b2)
 314   {
 315     byte[] b3 = new byte[b1.length+b2.length];
 316     System.arraycopy(b1, 0, b3, 0, b1.length);
 317     System.arraycopy(b2, 0, b3, b1.length, b2.length);
 318     return b3;
 319   }
 320
 321   /**
 322    * See {@link #trim(byte[],int,int)}.
 323    */
 324   public static byte[] trim(byte[] buffer, int len)
 325   {
 326     return trim(buffer, 0, len);
 327   }
 328
 329   /**
 330    * Returns a portion of a byte array, possibly zero-filled.
 331    *
 332    * @param buffer The byte array to trim.
 333    * @param off The offset to begin reading at.
 334    * @param len The number of bytes to return. This value can be larger
 335    *        than <i>buffer.length - off</i>, in which case the rest of the
 336    *        returned byte array will be filled with zeros.
 337    * @throws IndexOutOfBoundsException If <i>off</i> or <i>len</i> is
 338    *         negative, or if <i>off</i> is larger than the byte array's
 339    *         length.
 340    * @return The trimmed byte array.
 341    */
 342   public static byte[] trim(byte[] buffer, int off, int len)
 343   {
 344     if (off < 0 || len < 0 || off > buffer.length)
 345       throw new IndexOutOfBoundsException("max=" + buffer.length +
 346                                           " off=" + off + " len=" + len);
 347     if (off == 0 && len == buffer.length)
 348       return buffer;
 349     byte[] b = new byte[len];
 350     System.arraycopy(buffer, off, b, 0, Math.min(len, buffer.length - off));
 351     return b;
 352   }
 353
 354   /**
 355    * Returns the byte array representation of the given big integer with
 356    * the leading zero byte (if any) trimmed off.
 357    *
 358    * @param bi The integer to trim.
 359    * @return The byte representation of the big integer, with any leading
 360    *   zero removed.
 361    */
 362   public static byte[] trim(BigInteger bi)
 363   {
 364     byte[] buf = bi.toByteArray();
 365     if (buf[0] == 0x00 && !bi.equals(BigInteger.ZERO))
 366       {
 367         return trim(buf, 1, buf.length - 1);
 368       }
 369     else
 370       {
 371         return buf;
 372       }
 373   }
 374
 375   /**
 376    * Returns the integer value of <code>{@link
 377    * java.lang.System#currentTimeMillis()} / 1000</code>.
 378    *
 379    * @return The current time, in seconds.
 380    */
 381   public static int unixTime()
 382   {
 383     return (int) (System.currentTimeMillis() / 1000L);
 384   }
 385
 386   /**
 387    * Transform an Object array into another by calling the given method
 388    * on each object. The returned object array will have the runtime
 389    * type of <i>returnType</i>. For example, the following will transform
 390    * array of objects into their String representations, returning a String
 391    * array. For example:
 392    *
 393    * <blockquote><p><code>
 394    * String[] strings = (String[]) Util.transform(array, String.class,
 395    * "toString", null);
 396    * </code></p></blockquote>
 397    *
 398    * <p>If any element of the given array is <tt>null</tt>, then that
 399    * entry in the returned array will also be <tt>null</tt>.
 400    *
 401    * @param array The array to transform. It does not need to be of
 402    *        uniform type.
 403    * @param returnType The desired return type of the returned array.
 404    *        This must by the <i>component</i> type, not the array type.
 405    * @param method The name of the method to invoke from each object.
 406    * @param args The arguments to pass to the method, or <tt>null</tt>
 407    *        if the method takes no arguments.
 408    * @throws InvocationTargetException If an exception occurs while
 409    *         calling <i>method</i> of any object.
 410    * @throws NoSuchMethodException If <i>method</i> is not the name of
 411    *         a valid method of any component of the array.
 412    * @throws ClassCastException If the returned object from the method
 413    *         is not assignable to the return type.
 414    * @throws IllegalArgumentException If <i>args</i> is not appropriate
 415    *         for <i>method</i>
 416    * @throws IllegalAccessException If <i>method</i> is not accessible.
 417    * @throws SecurityException If <i>method</i> is not accessible.
 418    * @return An array containing the output of <i>method</i> called on
 419    *         each element of <i>array</i> with <i>args</i>. The return type
 420    *         of the array will be an array of <i>returnType</i>.
 421    */
 422   static Object[] transform(Object[] array, Class returnType,
 423                             String method, Object[] args)
 424     throws InvocationTargetException, NoSuchMethodException,
 425            IllegalAccessException
 426   {
 427     if (args == null)
 428       args = new Object[0];
 429     Object[] result = (Object[]) Array.newInstance(returnType, array.length);
 430     Class[] argsClasses = new Class[args.length];
 431     for (int i = 0; i < args.length; i++)
 432       {
 433         argsClasses[i] = args[i].getClass();
 434       }
 435     for (int i = 0; i < array.length; i++)
 436       {
 437         if (array[i] == null)
 438           {
 439             result[i] = null;
 440             continue;
 441           }
 442         Class objClass = array[i].getClass();
 443         Method objMethod = objClass.getMethod(method, argsClasses);
 444         Object o = objMethod.invoke(array[i], args);
 445         if (!returnType.isAssignableFrom(o.getClass()))
 446           throw new ClassCastException();
 447         result[i] = o;
 448       }
 449     return result;
 450   }
 451
 452   /**
 453    * Get a system property as a privileged action.
 454    *
 455    * @param name The name of the property to get.
 456    * @return The property named <i>name</i>, or null if the property is
 457    *   not set.
 458    * @throws SecurityException If the Jessie code still does not have
 459    *   permission to read the property.
 460    */
 461   @Deprecated static String getProperty(final String name)
 462   {
 463     return (String) AccessController.doPrivileged(
 464       new PrivilegedAction()
 465       {
 466         public Object run()
 467         {
 468           return System.getProperty(name);
 469         }
 470       }
 471     );
 472   }
 473
 474   /**
 475    * Get a security property as a privileged action.
 476    *
 477    * @param name The name of the property to get.
 478    * @return The property named <i>name</i>, or null if the property is
 479    *   not set.
 480    * @throws SecurityException If the Jessie code still does not have
 481    *   permission to read the property.
 482    */
 483   @Deprecated static String getSecurityProperty(final String name)
 484   {
 485     return (String) AccessController.doPrivileged(
 486       new PrivilegedAction()
 487       {
 488         public Object run()
 489         {
 490           return Security.getProperty(name);
 491         }
 492       }
 493     );
 494   }
 495 }