001    /* BinaryRefAddr.java -- RefAddr that uses a byte array as content.
002       Copyright (C) 2001 Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010     
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    package javax.naming;
039    
040    import java.util.Arrays;
041    
042    /**
043     * RefAddr that uses a byte array as content.
044     * This can be used to reference objects that can only be represented as
045     * byte arrays.
046     *
047     * @see Reference
048     * @since 1.3
049     * @author Mark Wielaard (mark@klomp.org)
050     */
051    public class BinaryRefAddr extends RefAddr
052    {
053      static final long serialVersionUID = -3415254970957330361L;
054            
055      /**
056       * The possibly null content of this RefAddr.
057       * Set by the constructor and returned by getContent.
058       */
059      private final byte[] buf;
060    
061      /**
062       * Contructs a new BinaryRefAddr with the given type and content.
063       * The complete content of the byte array is copied to a new array.
064       */
065      public BinaryRefAddr (String addrType, byte[] buf)
066      {
067        this(addrType, buf, 0, buf.length);
068      }
069    
070      /**
071       * Contructs a new BinaryRefAddr with the given type and the content
072       * taken from the given byte array.
073       * The content of the byte array is copied to a new array.
074       */
075      public BinaryRefAddr (String addrType, byte[] buf, int off, int length)
076      {
077        super(addrType);
078        this.buf = new byte[length];
079        System.arraycopy(buf, off, this.buf, 0, length);
080      }
081    
082      /**
083       * Returns the byte array contents as given to the constructor.
084       * The returned byte array is shared with this object and other callers.
085       * Changing the content of the buffer is discouraged and should only be
086       * done when the byte array is locked.
087       */
088      public Object getContent ()
089      {
090        return buf;
091      }
092    
093      /**
094       * Checks if the object is a BinaryRefAddr with the same type and with the
095       * same bytes in the content.
096       *
097       * @return true if the given object is an instance of BinaryRefAddr,
098       *         the addrType is the same as this addrType and the bytes of the
099       *         content are the same.
100       */
101      public boolean equals(Object o)
102      {
103        if (o instanceof BinaryRefAddr)
104          {
105            BinaryRefAddr refAddr = (BinaryRefAddr) o;
106            if (this.getType().equals(refAddr.getType()))
107            {
108              byte[] c1 = (byte[]) this.getContent();
109              byte[] c2 = (byte[]) refAddr.getContent();
110              return Arrays.equals(c1, c2);
111            }
112          }
113        return false;
114      }
115    
116      /**
117       * Returns the hashCode which is the hasCode of the String returned by
118       * <code>getType()</code> plus the hashCode of the byte array returned by
119       * <code>getContent</code>. The hashCode of the byte array is calculated
120       * by taking the xor of all the bytes in the array, or zero when there are
121       * no bytes in the array.
122       */
123      public int hashCode()
124      {
125        int result = 0;
126        byte[] b = (byte[]) getContent();
127        for (int i=0; i < b.length; i++)
128          result = result^b[i];
129    
130        return getType().hashCode() + result;
131      }
132    
133      private static char[] hex = {'0', '1', '2', '3', '4', '5', '6', '7',
134                                   '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'};
135      /**
136       * Returns a String representation of the RefAddr. Only the first 32 bytes
137       * of the content are added as hex encoded characters.
138       * Should only be used for debugging purposes.
139       */
140      public String toString()
141      {
142        StringBuffer sb = new StringBuffer("[RefAddr type: ");
143        sb.append(getType());
144        sb.append(" content: 0x");
145        byte[] b = (byte[]) getContent();
146        for (int i=0; i < b.length && i < 32; i++)
147          {
148            sb.append(hex[(b[i]&0xf0)>>4]);
149            sb.append(hex[b[i]&0x0f]);
150          }
151        if (b.length > 32)
152          sb.append("...");
153        sb.append("]");
154        return sb.toString();
155      }
156    }