jurt/com/sun/star/lib/uno/environments/remote/ThreadId.java

   1 /*
   2  * This file is part of the LibreOffice project.
   3  *
   4  * This Source Code Form is subject to the terms of the Mozilla Public
   5  * License, v. 2.0. If a copy of the MPL was not distributed with this
   6  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   7  *
   8  * This file incorporates work covered by the following license notice:
   9  *
  10  *   Licensed to the Apache Software Foundation (ASF) under one or more
  11  *   contributor license agreements. See the NOTICE file distributed
  12  *   with this work for additional information regarding copyright
  13  *   ownership. The ASF licenses this file to you under the Apache
  14  *   License, Version 2.0 (the "License"); you may not use this file
  15  *   except in compliance with the License. You may obtain a copy of
  16  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  17  */
  18
  19 package com.sun.star.lib.uno.environments.remote;
  20
  21 import com.sun.star.uno.UnoRuntime;
  22 import java.io.UnsupportedEncodingException;
  23 import java.math.BigInteger;
  24 import java.util.Arrays;
  25
  26 public final class ThreadId {
  27     public static ThreadId createFresh() {
  28         BigInteger c;
  29         synchronized (PREFIX) {
  30             c = count;
  31             count = count.add(BigInteger.ONE);
  32         }
  33         try {
  34             return new ThreadId((PREFIX + c).getBytes("UTF-8"));
  35         } catch (UnsupportedEncodingException e) {
  36             throw new RuntimeException("this cannot happen: " + e);
  37         }
  38     }
  39
  40     public ThreadId(byte[] id) {
  41         this.id = id;
  42     }
  43
  44     /**
  45      * Indicates whether some other object is equal to this one.
  46      *
  47      * @param obj the reference object with which to compare.
  48      * @return <code>true</code> if this object is the same as the obj argument;
  49      * <code>false</code> otherwise.
  50      *
  51      * @see java.lang.Object#equals
  52      */
  53     @Override
  54     public boolean equals(Object obj) {
  55         return obj instanceof ThreadId
  56             && Arrays.equals(id, ((ThreadId) obj).id);
  57     }
  58
  59     /**
  60      * Returns a hash code value for the object.
  61      *
  62      * @return a hash code value for this object.
  63      * @see java.lang.Object#hashCode
  64      */
  65     @Override
  66     public int hashCode() {
  67         int h = hash;
  68         if (h == 0) {
  69             // Same algorithm as java.util.List.hashCode (also see Java 1.5
  70             // java.util.Arrays.hashCode(byte[])):
  71             h = 1;
  72             for (int i = 0; i < id.length; ++i) {
  73                 h = 31 * h + id[i];
  74             }
  75             hash = h;
  76         }
  77         return h;
  78     }
  79
  80     /**
  81      * Returns a string representation of the object.
  82      *
  83      * @return a string representation of the object.
  84      * @see java.lang.Object#toString
  85      */
  86     @Override
  87     public String toString() {
  88         StringBuffer b = new StringBuffer("[ThreadId:");
  89         for (int i = 0; i < id.length; ++i) {
  90             String n = Integer.toHexString(id[i] & 0xFF);
  91             if (n.length() == 1) {
  92                 b.append('0');
  93             }
  94             b.append(n);
  95         }
  96         b.append(']');
  97         return b.toString();
  98     }
  99
 100     public byte[] getBytes() {
 101         return id;
 102     }
 103
 104     private static final String PREFIX = "java:" + UnoRuntime.getUniqueKey() + ":";
 105     private static BigInteger count = BigInteger.ZERO;
 106
 107     private final byte[] id;
 108     private int hash = 0;
 109 }