/*
    * $Header: /cvsroot/jdbforms/dbforms/src/org/dbforms/util/MessageResource.java,v 1.10 2004/08/18 12:26:09 hkollmann Exp $
    * $Revision: 1.10 $
    * $Date: 2004/08/18 12:26:09 $
    *
    * DbForms - a Rapid Application Development Framework
    * Copyright (C) 2001 Joachim Peer <joepeer@excite.com>
    *
    * This library is free software; you can redistribute it and/or
   * modify it under the terms of the GNU Lesser General Public
   * License as published by the Free Software Foundation; either
   * version 2.1 of the License, or (at your option) any later version.
   *
   * This library is distributed in the hope that it will be useful,
   * but WITHOUT ANY WARRANTY; without even the implied warranty of
   * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
   * Lesser General Public License for more details.
   *
   * You should have received a copy of the GNU Lesser General Public
   * License along with this library; if not, write to the Free Software
   * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
   */
  
  package org.dbforms.util;
  
  import java.util.HashMap;
  import java.util.Locale;
  import java.util.ResourceBundle;
  
  
  
  /***
   * base class for handling message resources
   *
   * @author Henner Kollmann
   */
  public class MessageResource {
     /***
      * Use of HashMap for allowing null value (ReourceBundle) and avoiding to
      * call getBundle each time if resources file is not present.
      */
     private HashMap hashResources = new HashMap();
     private String  subClass = null;
  
     /***
      * Creates a new MessageResource object.
      *
      * @param subClass DOCUMENT ME!
      */
     public MessageResource(String subClass) {
        this.subClass = subClass;
     }
  
     /***
      * Retrieve message from ResourceBundle.  If the ResourceBundle is not yet
      * cached, cache it and retreive message.
      *
      * @param msgmsg </code> : Message key to lookup.
      * @param locloc </code> : Locale object to map message with good
      *        ResourceBundle.
      *
      * @return <code>String</code> : Message resolve, null if not found.
      */
     public String getMessage(String msg,
                              Locale loc) {
        if (subClass == null) {
           return null;
        }
  
        if (loc == null) {
           return null;
        }
  
        ResourceBundle rb = null;
  
        // Faster than String (immuable) concatenation
        String key = new StringBuffer().append(loc.getLanguage())
                                       .append("_")
                                       .append(loc.getCountry())
                                       .append("_")
                                       .append(loc.getVariant())
                                       .toString();
  
        if (hashResources.containsKey(key)) {
           rb = (ResourceBundle) hashResources.get(key);
        } else {
           try {
              rb = ResourceBundle.getBundle(subClass, loc);
           } catch (Exception e) {
              rb = null;
           }
  
           // Put the ResourceBundle or null value in HashMap with the key
           hashResources.put(key, rb);
        }
  
        String s = null;
  
        if (rb != null) {
          try {
             s = rb.getString(msg);
          } catch (Exception e) {
             s = null;
          }
       }
 
       return s;
    }
 
 
    /***
     * Retrieve message from ResourceBundle and replace parameter "{x}" with
     * values in parms array.
     *
     * @param msgmsg </code> : Message key to lookup.
     * @param locloc </code> : Locale object to map message with good
     *        ResourceBundle.
     * @param parmsparms[] </code> : Parameters to replace "{x}" in message .
     *
     * @return <code>String</code> : Message resolve with parameter replaced,
     *         null if message key not found.
     */
    public String getMessage(String   msg,
                             Locale   loc,
                             String[] parms) {
       String result = getMessage(msg, loc);
 
       if (result == null) {
          return null;
       }
 
       String search = null;
 
       for (int i = 0; i < parms.length; i++) {
          search = "{" + i + "}";
          result = replaceAll(result, search, parms[i]);
       }
 
       return result;
    }
 
 
    /***
     * DOCUMENT ME!
     *
     * @return DOCUMENT ME!
     */
    public String getSubClass() {
       return subClass;
    }
 
 
    /***
     * Replace all expression {...} by the appropriate string.
     *
     * @param strstr </code> : Original string.
     * @param searchsearch </code> : Expression to search.
     * @param replacereplace </code> : Replacement string.
     *
     * @return <code>String</code> : The string with all expression replaced.
     */
    private String replaceAll(String str,
                              String search,
                              String replace) {
       StringBuffer result = null;
       int          oldpos = 0;
 
       do {
          int pos = str.indexOf(search, oldpos);
 
          if (pos < 0) {
             break;
          }
 
          if (result == null) {
             result = new StringBuffer();
          }
 
          result.append(str.substring(oldpos, pos));
 
          result.append(replace);
 
          pos += search.length();
          oldpos = pos;
       } while (true);
 
       if (oldpos == 0) {
          return str;
       } else {
          result.append(str.substring(oldpos));
 
          return new String(result);
       }
    }
 }