001/* StringHolder.java -- 002 Copyright (C) 2005 Free Software Foundation, Inc. 003 004This file is part of GNU Classpath. 005 006GNU Classpath is free software; you can redistribute it and/or modify 007it under the terms of the GNU General Public License as published by 008the Free Software Foundation; either version 2, or (at your option) 009any later version. 010 011GNU Classpath is distributed in the hope that it will be useful, but 012WITHOUT ANY WARRANTY; without even the implied warranty of 013MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014General Public License for more details. 015 016You should have received a copy of the GNU General Public License 017along with GNU Classpath; see the file COPYING. If not, write to the 018Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 01902110-1301 USA. 020 021Linking this library statically or dynamically with other modules is 022making a combined work based on this library. Thus, the terms and 023conditions of the GNU General Public License cover the whole 024combination. 025 026As a special exception, the copyright holders of this library give you 027permission to link this library with independent modules to produce an 028executable, regardless of the license terms of these independent 029modules, and to copy and distribute the resulting executable under 030terms of your choice, provided that you also meet, for each linked 031independent module, the terms and conditions of the license of that 032module. An independent module is a module which is not derived from 033or based on this library. If you modify this library, you may extend 034this exception to your version of the library, but you are not 035obligated to do so. If you do not wish to do so, delete this 036exception statement from your version. */ 037 038 039package org.omg.CORBA; 040 041import gnu.CORBA.typecodes.StringTypeCode; 042 043import org.omg.CORBA.portable.InputStream; 044import org.omg.CORBA.portable.OutputStream; 045import org.omg.CORBA.portable.Streamable; 046 047/** 048 * A holder for CORBA <code>string</code> that is mapped into 049 * java <code>String</code>. 050 * 051 * The holders have several application areas. The end user usually 052 * sees them implementing CORBA methods where the primitive type 053 * is passed by reference. While CORBA (or, for example, C) supports 054 * this, the java does not and a wrapper class is required. 055 * 056 * @author Audrius Meskauskas (AudriusA@Bioinformatics.org) 057 */ 058public final class StringHolder 059 implements Streamable 060{ 061 /** 062 * The default type code for this holder. 063 */ 064 private static final StringTypeCode t_string = 065 new StringTypeCode(TCKind.tk_string); 066 067 /** 068 * The <code>String</code> (CORBA <code>string</code>) value, 069 * held by this StringHolder. 070 */ 071 public String value; 072 073 /** 074 * Constructs an instance of StringHolder, 075 * initializing {@link #value} to <code>null</code>. 076 */ 077 public StringHolder() 078 { 079 } 080 081 /** 082 * Constructs an instance of StringHolder, 083 * initializing {@link #value} to the given <code>String</code>. 084 * 085 * @param initial_value a value that will be assigned to the 086 * {@link #value} field. 087 */ 088 public StringHolder(String initial_value) 089 { 090 value = initial_value; 091 } 092 093 /** 094 * Fill in the {@link #value } field by reading the required data 095 * from the given stream. For <code>string</code>, the functionality 096 * is delegated to 097 * {@link org.omg.CORBA.portable.InputStream#read_string}. 098 * 099 * @param input the input stream to read from. 100 */ 101 public void _read(InputStream input) 102 { 103 value = input.read_string(); 104 } 105 106 /** 107 * Returns the TypeCode, corresponding the CORBA type that is stored 108 * using this holder. The {@link TypeCode#length()} method of the 109 * returned typecode always returns 0. 110 */ 111 public TypeCode _type() 112 { 113 return t_string; 114 } 115 116 /** 117 * Write the {@link #value } field to the given stream. 118 * For <code>string</code>, the functionality 119 * is delegated to 120 * {@link org.omg.CORBA.portable.OutputStream#write_string(String) }. 121 * 122 * @param output the output stream to write into. 123 */ 124 public void _write(OutputStream output) 125 { 126 output.write_string(value); 127 } 128}