libjava/classpath/gnu/CORBA/GIOP/RequestHeader.java

   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 }