libjava/classpath/java/io/ObjectStreamConstants.java

   1 /* ObjectStreamConstants.java -- Interface containing constant values
   2    used in reading and writing serialized objects
   3    Copyright (C) 1998, 1999, 2003, 2006 Free Software Foundation, Inc.
   4
   5 This file is part of GNU Classpath.
   6
   7 GNU Classpath is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU Classpath is distributed in the hope that it will be useful, but
  13 WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  15 General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU Classpath; see the file COPYING.  If not, write to the
  19 Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
  20 02110-1301 USA.
  21
  22 Linking this library statically or dynamically with other modules is
  23 making a combined work based on this library.  Thus, the terms and
  24 conditions of the GNU General Public License cover the whole
  25 combination.
  26
  27 As a special exception, the copyright holders of this library give you
  28 permission to link this library with independent modules to produce an
  29 executable, regardless of the license terms of these independent
  30 modules, and to copy and distribute the resulting executable under
  31 terms of your choice, provided that you also meet, for each linked
  32 independent module, the terms and conditions of the license of that
  33 module.  An independent module is a module which is not derived from
  34 or based on this library.  If you modify this library, you may extend
  35 this exception to your version of the library, but you are not
  36 obligated to do so.  If you do not wish to do so, delete this
  37 exception statement from your version. */
  38
  39
  40 package java.io;
  41
  42 /**
  43  * This interface contains constants that are used in object
  44  * serialization.  This interface is used by <code>ObjectOutputStream</code>,
  45  * <code>ObjectInputStream</code>, and <code>ObjectStreamClass</code>.
  46  * The values for these constants are specified by the Java library
  47  * specification.
  48  *
  49  * @since 1.1
  50  */
  51 public interface ObjectStreamConstants
  52 {
  53   /**
  54    * The serialization stream protocol version 1. This version was
  55    * the default serialization protocol before JDK 1.2.
  56    *
  57    * @see ObjectOutputStream#useProtocolVersion(int)
  58    * @since 1.2
  59    */
  60   int PROTOCOL_VERSION_1 = 1;
  61
  62   /**
  63    * The serialization stream protocol version 2. This version is
  64    * used as the default serialization protocol since JDK 1.2.
  65    *
  66    * @see ObjectOutputStream#useProtocolVersion(int)
  67    * @since 1.2
  68    */
  69   int PROTOCOL_VERSION_2 = 2;
  70
  71   /**
  72    * The magic number that is written as part of the stream header.
  73    */
  74   short STREAM_MAGIC = (short)0xaced;
  75
  76   /**
  77    * The stream version number that is written as part of the stream header.
  78    * Note that this is different from the protocol version that specifies
  79    * the data format for the stream.
  80    */
  81   short STREAM_VERSION = 5;
  82
  83   /**
  84    * Token value to designate a <code>null</code> reference in the stream.
  85    */
  86   byte TC_NULL = (byte)112;            //0x70
  87
  88   /**
  89    * Token value to designate a reference to an already serialized object.
  90    */
  91   byte TC_REFERENCE = (byte)113;       //0x71
  92
  93   /**
  94    * Token value to designate a class descriptor is next in the stream.
  95    */
  96   byte TC_CLASSDESC = (byte)114;       //0x72
  97
  98   /**
  99    * Token value to designate a new object is next in the stream.
 100    */
 101   byte TC_OBJECT = (byte)115;          //0x73
 102
 103   /**
 104    * Token value to designate a new string is next in the stream.
 105    */
 106   byte TC_STRING = (byte)116;          //0x74
 107
 108   /**
 109    * Token value to designate a new array is next in the stream.
 110    */
 111   byte TC_ARRAY = (byte)117;           //0x75
 112
 113   /**
 114    * Token reference to designate a reference to a class.
 115    */
 116   byte TC_CLASS = (byte)118;           //0x76
 117
 118   /**
 119    * Token value to designate a block of primitive data is next in the stream.
 120    * The next byte in the stream holds the size of the block (in bytes).
 121    */
 122   byte TC_BLOCKDATA = (byte)119;       //0x77
 123
 124   /**
 125    * Token value to designate the end of a block of primitve data.
 126    */
 127   byte TC_ENDBLOCKDATA = (byte)120;    //0x78
 128
 129   /**
 130    * Token value to designate a reset of the stream state.
 131    */
 132   byte TC_RESET = (byte)121;           //0x79
 133
 134   /**
 135    * Token value to designate a long block of primitive data is next in the
 136    * stream. The next long in the stream holds the size of the block
 137    * (in bytes).
 138    */
 139   byte TC_BLOCKDATALONG = (byte)122;   //0x7A
 140
 141   /**
 142    * Token value to designate an exception occured during serialization.
 143    */
 144   byte TC_EXCEPTION = (byte)123;       //0x7B
 145
 146   /**
 147    * Token value to designate a long string is next in the stream.
 148    */
 149   byte TC_LONGSTRING = (byte)124;      //0x7C
 150
 151   /**
 152    * Token value to designate a proxy class descriptor is next in the stream.
 153    */
 154   byte TC_PROXYCLASSDESC = (byte)125;  //0x7D
 155
 156   /**
 157    * Token value to designate an enum constant is next in the stream.
 158    *
 159    * @since 1.5
 160    */
 161   byte TC_ENUM = (byte)126;            //0x7E
 162
 163   /**
 164    * The first token value.
 165    */
 166   byte TC_BASE = TC_NULL;
 167
 168   /**
 169    * The last token value.
 170    */
 171   byte TC_MAX = TC_ENUM;
 172
 173   /**
 174    * The first handle that will be assigned to an object, for later references.
 175    */
 176   int baseWireHandle = 0x7e0000;
 177
 178   /**
 179    * Flag used in <code>ObjectStreamClass</code> to designate that the class
 180    * defines the <code>writeObject</code> method.
 181    */
 182   byte SC_WRITE_METHOD = 0x01;
 183
 184   /**
 185    * Flag used in <code>ObjectStreamClass</code> to designate that the class
 186    * is serializeable.
 187    */
 188   byte SC_SERIALIZABLE = 0x02;
 189
 190   /**
 191    * Flag used in <code>ObjectStreamClass</code> to designate that the class
 192    * is externalizable.
 193    */
 194   byte SC_EXTERNALIZABLE = 0x04;
 195
 196   /**
 197    * Flag used in <code>ObjectStreamClass</code> to designate that
 198    * externalizable data is written in block data mode.
 199    *
 200    * @since 1.2
 201    */
 202   byte SC_BLOCK_DATA = 0x08;
 203
 204   /**
 205    * Flag used in <code>ObjectStreamClass</code> to designate that the class
 206    * is an enum constant.
 207    *
 208    * @since 1.5
 209    */
 210   byte SC_ENUM = 0x10;
 211
 212   /**
 213    * Constant for use with a <code>SecurityManager</code> to check if
 214    * substitution of objects is allowed.
 215    */
 216   SerializablePermission SUBSTITUTION_PERMISSION
 217     = new SerializablePermission("enableSubstitution");
 218
 219   /**
 220    * Constant for use with a <code>SecurityManager</code> to check if
 221    * overriding of the <code>writeObject</code> and <code>readObject</code>
 222    * methods is allowed.
 223    */
 224   SerializablePermission SUBCLASS_IMPLEMENTATION_PERMISSION
 225     = new SerializablePermission("enableSubclassImplementation");
 226 }
 227