Source for gnu.CORBA.EmptyExceptionHolder

   1: /* EmptyStructHolder.java --
   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;
  40: 
  41: import org.omg.CORBA.BAD_OPERATION;
  42: import org.omg.CORBA.TypeCode;
  43: import org.omg.CORBA.UNKNOWN;
  44: import org.omg.CORBA.portable.InputStream;
  45: import org.omg.CORBA.portable.OutputStream;
  46: import org.omg.CORBA.portable.Streamable;
  47: 
  48: /**
  49:  * This holder can store any CORBA exception that has no user defined fields.
  50:  * Only the repository ID is written when the method {@link #_write} is called.
  51:  * The _read method is not supported for this holder.
  52:  *
  53:  * @author Audrius Meskauskas, Lithuania (AudriusA@Bioinformatics.org)
  54:  */
  55: public class EmptyExceptionHolder
  56:   implements Streamable
  57: {
  58:   /**
  59:    * The wrapped exception.
  60:    */
  61:   public Throwable value;
  62: 
  63:   /**
  64:    * The typecode of the wrapped exception.
  65:    */
  66:   public TypeCode typecode;
  67: 
  68:   /**
  69:    * Create the exception holder, initialised to the given values.
  70:    *
  71:    * @param an_exception the wrapped exception.
  72:    * @param an_id the exception repository id.
  73:    */
  74:   public EmptyExceptionHolder(Throwable an_exception, TypeCode a_typecode)
  75:   {
  76:     value = an_exception;
  77:     typecode = a_typecode;
  78:   }
  79: 
  80:   /**
  81:    * Reads the exception from the input stream.
  82:    *
  83:    * The value field obtains the value of either the read exception or
  84:    * the UNKNOWN if the repository ID does not match
  85:    * the exception from the reachable code.
  86:    */
  87:   public void _read(InputStream input)
  88:   {
  89:     String id = input.read_string();
  90:     Object ex = ObjectCreator.Idl2Object(id);
  91:     if (ex == null)
  92:       value = new UNKNOWN(id);
  93:     else
  94:       value = (Throwable) ex;
  95:   }
  96: 
  97:   /**
  98:    * Return the typecode of the stored exception.
  99:    *
 100:    * @return the value, passed as a_typecode in constructor.
 101:    */
 102:   public TypeCode _type()
 103:   {
 104:     return typecode;
 105:   }
 106: 
 107:   /**
 108:    * Write the exception into the give output stream. Writes the
 109:    * repository id that is taken from the typecode. This method also
 110:    * works when no helper class is available.
 111:    *
 112:    * @param output a stream to write into.
 113:    *
 114:    * @throws BAD_OPERATION if the value for the holder is not set or
 115:    * the typecode cannot provide repository id.
 116:    */
 117:   public void _write(OutputStream output)
 118:   {
 119:     try
 120:       {
 121:         output.write_string(typecode.id());
 122:       }
 123:     catch (Exception ex)
 124:       {
 125:         BAD_OPERATION bad = new BAD_OPERATION();
 126:         bad.minor = Minor.CDR;
 127:         bad.initCause(ex);
 128:         throw bad;
 129:       }
 130:   }
 131: }