Source for gnu.CORBA.GIOP.RequestHeader

   1: /* RequestHeader.java -- The GIOP 1.0 request message.
   2:    Copyright (C) 2005 Free Software Foundation, Inc.
   3: 
   4: This file is 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, or (at your option)
   9: 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; see the file COPYING.  If not, write to the
  18: Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  19: 02110-1301 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.CORBA.GIOP;
  40: 
  41: import gnu.CORBA.CDR.AbstractCdrInput;
  42: import gnu.CORBA.CDR.AbstractCdrOutput;
  43: 
  44: import org.omg.CORBA.portable.IDLEntity;
  45: 
  46: /**
  47:  * The GIOP request message.
  48:  *
  49:  * @author Audrius Meskauskas (AudriusA@Bioinformatics.org)
  50:  */
  51: public abstract class RequestHeader
  52:   extends ContextHandler
  53:   implements IDLEntity
  54: {
  55:   /**
  56:    * The currently free request id. This field is incremented each time the new
  57:    * request header is constructed. To facilitate error detection, the first
  58:    * free id is equal to 0x01234567 (19088743).
  59:    */
  60:   private static int freeId = 0x01234567;
  61: 
  62:   /**
  63:    * The operation being invoked (IDL scope name).
  64:    */
  65:   public String operation;
  66: 
  67:   /**
  68:    * Identifies the object that is the target of the invocation.
  69:    */
  70:   public byte[] object_key;
  71: 
  72:   /**
  73:    * A value identifying the requesting principal. Initialised into a single
  74:    * zero byte.
  75:    *
  76:    * @deprecated by CORBA 2.2.
  77:    */
  78:   public byte[] requesting_principal;
  79: 
  80:   /**
  81:    * This is used to associate the reply message with the previous request
  82:    * message. Initialised each time by the different value, increasing form 1 to
  83:    * Integer.MAX_VALUE.
  84:    */
  85:   public int request_id = getNextId();
  86: 
  87:   /**
  88:    * If true, the response from the server is expected.
  89:    */
  90:   protected boolean response_expected = true;
  91: 
  92:   /**
  93:    * Get next free request id. The value of the free request id starts from
  94:    * 0x02345678, it is incremented each time this function is called and is
  95:    * reset to 1 after reaching Integer.MAX_VALUE.
  96:    *
  97:    * @return the next free request id.
  98:    */
  99:   public static synchronized int getNextId()
 100:   {
 101:     int f = freeId;
 102:     if (freeId == Integer.MAX_VALUE)
 103:       freeId = 1;
 104:     else
 105:       freeId++;
 106: 
 107:     return f;
 108:   }
 109: 
 110:   /**
 111:    * Set if the sender expects any response to this message.
 112:    */
 113:   public abstract void setResponseExpected(boolean expected);
 114: 
 115:   /**
 116:    * Return true if response is expected.
 117:    */
 118:   public abstract boolean isResponseExpected();
 119: 
 120:   /**
 121:    * Converts an byte array into hexadecimal string values. Used in various
 122:    * toString() methods.
 123:    */
 124:   public String bytes(byte[] array)
 125:   {
 126:     StringBuffer b = new StringBuffer();
 127:     for (int i = 0; i < array.length; i++)
 128:       {
 129:         b.append(Integer.toHexString(array[i] & 0xFF));
 130:         b.append(" ");
 131:       }
 132:     return b.toString();
 133:   }
 134: 
 135:   /**
 136:    * Reads the header from the stream.
 137:    *
 138:    * @param in a stream to read from.
 139:    */
 140:   public abstract void read(AbstractCdrInput in);
 141: 
 142:   /**
 143:    * Return a string representation.
 144:    */
 145:   public abstract String toString();
 146: 
 147:   /**
 148:    * Writes the header to the stream.
 149:    *
 150:    * @param out a stream to write into.
 151:    */
 152:   public abstract void write(AbstractCdrOutput out);
 153: 
 154: }