001    /* ThreadPolicyValue.java --
002       Copyright (C) 2005, 2006 Free Software Foundation, Inc.
003    
004    This file is part of GNU Classpath.
005    
006    GNU Classpath is free software; you can redistribute it and/or modify
007    it under the terms of the GNU General Public License as published by
008    the Free Software Foundation; either version 2, or (at your option)
009    any later version.
010    
011    GNU Classpath is distributed in the hope that it will be useful, but
012    WITHOUT ANY WARRANTY; without even the implied warranty of
013    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
014    General Public License for more details.
015    
016    You should have received a copy of the GNU General Public License
017    along with GNU Classpath; see the file COPYING.  If not, write to the
018    Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
019    02110-1301 USA.
020    
021    Linking this library statically or dynamically with other modules is
022    making a combined work based on this library.  Thus, the terms and
023    conditions of the GNU General Public License cover the whole
024    combination.
025    
026    As a special exception, the copyright holders of this library give you
027    permission to link this library with independent modules to produce an
028    executable, regardless of the license terms of these independent
029    modules, and to copy and distribute the resulting executable under
030    terms of your choice, provided that you also meet, for each linked
031    independent module, the terms and conditions of the license of that
032    module.  An independent module is a module which is not derived from
033    or based on this library.  If you modify this library, you may extend
034    this exception to your version of the library, but you are not
035    obligated to do so.  If you do not wish to do so, delete this
036    exception statement from your version. */
037    
038    
039    package org.omg.PortableServer;
040    
041    import gnu.CORBA.Minor;
042    
043    import org.omg.CORBA.BAD_OPERATION;
044    import org.omg.CORBA.BAD_PARAM;
045    import org.omg.CORBA.portable.IDLEntity;
046    
047    import java.io.Serializable;
048    
049    /**
050     * Defines the possible values for the POA thread policy.
051     *
052     * This enumeration can obtain the following values:
053     * <ul>
054     * <li>ORB_CTRL_MODEL Each object in POA has a separate serving thread
055     * and a separate server socket, listening on the objects individual
056     * port. Additionally, when the request is accepted, it is also
057     * served in a separate thread, so several requests to the same
058     * object can be processed in parallel. The servant can always get
059     * the Id and POA of the object it is currently serving by
060     * invoking {@link Servant#_object_id()} and {@link Servant#_poa}.
061     * These two methods use thread to data map and must work correctly
062     * even then the servant code is executed in several parallel threads.
063     * </li>
064     * <li>SINGLE_THREAD_MODEL All objects in POA share the same server
065     * socket and are served in the same thread. This model is applicable
066     * when the number of objects is greater than the number of threads
067     * and (or) ports, supported by the system.</li>
068     * </ul>
069     * OMG also defines a MAIN_THREAD_MODEL, currently not supported by
070     * the java API.
071     *
072     * @author Audrius Meskauskas, Lithuania (AudriusA@Bioinformatics.org)
073     */
074    public class ThreadPolicyValue
075      implements Serializable, IDLEntity
076    {
077      /**
078       * Use serialVersionUID (v1.4) for interoperability.
079       */
080      private static final long serialVersionUID = -8874988828297141512L;
081    
082      /**
083       * The value field for the current instance.
084       */
085      private final int _value;
086    
087      /**
088      * The possible value of this enumeration (ORB_CTRL_MODEL).
089      */
090      public static final int _ORB_CTRL_MODEL = 0;
091    
092      /**
093       * An instance of ThreadPolicyValue, initialized to ORB_CTRL_MODEL.
094       */
095      public static final ThreadPolicyValue ORB_CTRL_MODEL =
096        new ThreadPolicyValue(_ORB_CTRL_MODEL);
097    
098      /**
099      * The possible value of this enumeration (SINGLE_THREAD_MODEL).
100      */
101      public static final int _SINGLE_THREAD_MODEL = 1;
102    
103      /**
104       * An instance of ThreadPolicyValue, initialized to SINGLE_THREAD_MODEL.
105       */
106      public static final ThreadPolicyValue SINGLE_THREAD_MODEL =
107        new ThreadPolicyValue(_SINGLE_THREAD_MODEL);
108    
109      /**
110       * The private array that maps integer codes to the enumeration
111       * values.
112       */
113      private static final ThreadPolicyValue[] enume =
114        new ThreadPolicyValue[] { ORB_CTRL_MODEL, SINGLE_THREAD_MODEL };
115    
116      /**
117       * The private array of state names.
118       */
119      private static final String[] state_names =
120        new String[] { "ORB_CTRL_MODEL", "SINGLE_THREAD_MODEL" };
121    
122      /**
123       * Normally, no new instances are required, so the constructor is protected.
124       */
125      protected ThreadPolicyValue(int a_value)
126      {
127        _value = a_value;
128      }
129    
130      /**
131       * Returns the ThreadPolicyValue, matching the given integer constant.
132       *
133       * @param code one of _ORB_CTRL_MODEL, _SINGLE_THREAD_MODEL.
134       * @return one of ORB_CTRL_MODEL, SINGLE_THREAD_MODEL.
135       * @throws BAD_PARAM if the parameter is not one of the valid values.
136       */
137      public static ThreadPolicyValue from_int(int code)
138      {
139        try
140          {
141            return enume [ code ];
142          }
143        catch (ArrayIndexOutOfBoundsException ex)
144          {
145            BAD_OPERATION bad = new BAD_OPERATION("Invalid policy code " + code);
146            bad.minor = Minor.PolicyType;
147            throw bad;
148          }
149      }
150    
151      /**
152       * Returns a short string representation.
153       * @return the name of the current enumeration value.
154       */
155      public String toString()
156      {
157        return state_names [ _value ];
158      }
159    
160      /**
161       * Returns the integer code of the enumeration value.
162       * @return one of ORB_CTRL_MODEL, SINGLE_THREAD_MODEL.
163       */
164      public int value()
165      {
166        return _value;
167      }
168    }