realnumberfield.java

人工智能中Agent开发包。多 Agent 系统是处理自治 Agent 之间知识层的协作问题

/*
* The contents of this file are subject to the BT "ZEUS" Open Source 
* Licence (L77741), Version 1.0 (the "Licence"); you may not use this file 
* except in compliance with the Licence. You may obtain a copy of the Licence
* from $ZEUS_INSTALL/licence.html or alternatively from
* http://www.labs.bt.com/projects/agents/zeus/licence.htm
* 
* Except as stated in Clause 7 of the Licence, software distributed under the
* Licence is distributed WITHOUT WARRANTY OF ANY KIND, either express or 
* implied. See the Licence for the specific language governing rights and 
* limitations under the Licence.
* 
* The Original Code is within the package zeus.*.
* The Initial Developer of the Original Code is British Telecommunications
* public limited company, whose registered office is at 81 Newgate Street, 
* London, EC1A 7AJ, England. Portions created by British Telecommunications 
* public limited company are Copyright 1996-9. All Rights Reserved.
* 
* THIS NOTICE MUST BE INCLUDED ON ANY COPY OF THIS FILE
*/



package zeus.gui.fields;

import java.awt.Toolkit;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.text.*;
import javax.swing.event.*;


public class RealNumberField extends JTextField
                          implements FocusListener, DocumentListener  {

   protected static char MINUS = '-';
   protected static char PERIOD = '.';
   protected EventListenerList changeListeners = new EventListenerList();
   protected double min;
   protected double max;
   protected boolean range_check = false;
   protected boolean range_checked = false;

   public RealNumberField() {
      super();
   }
   public RealNumberField(double min, double max) {
      this();
      this.min = min;
      this.max = max;
      range_check = true;
      this.addFocusListener(this);
   }

   public void focusGained(FocusEvent evt) {
   }
   public void focusLost(FocusEvent evt) {
      if ( range_check && !range_checked ) {
         range_checked = true;
         try {
            double value = (Double.valueOf(getText())).doubleValue();
            if ( value < min || value > max ) {
               errorMsg();
               return;
            }
         }
         catch(NumberFormatException e) {
            errorMsg();
            return;
         }
      }
   }

   public void setText(Double obj) {
      setText(obj.toString());
   }
   public void setText(Integer obj) {
      setText(obj.toString());
   }
   public void setText(Long obj) {
      setText(obj.toString());
   }

   protected void errorMsg() {
      JOptionPane.showMessageDialog(this,
         "Illegal entry\nValue must be between " + min + " and " +
         max + " inclusive","Error", JOptionPane.ERROR_MESSAGE);
   }

   public void setValue(double value) {
      if ( range_check ) {
         if ( value < min || value > max ) {
            errorMsg();
            return;
         }
      }
      setText(Double.toString(value));
   }

   public Double getValue() {
      try {
         return new Double(getText());
      }
      catch(NumberFormatException e) {
         return null;
      }
   }

   public Double getValue(double def) {
      try {
         return new Double(getText());
      }
      catch(NumberFormatException e) {
         return new Double(def);
      }
   }

   protected Document createDefaultModel() {
      Document doc = new RealNumberFieldDocument();
      doc.addDocumentListener(this);
      return doc;
   }

   public void insertUpdate(DocumentEvent e) {
      range_checked = false;
      fireChanged();
   }
   public void removeUpdate(DocumentEvent e) {
      range_checked = false;
      fireChanged();
   }
   public void changedUpdate(DocumentEvent e) {
      range_checked = false;
      fireChanged();
   }

   static char[] numberSet = {
    '0', '1', '2', '3', '4', '5', '6', '7', '8', '9'
   };

   class RealNumberFieldDocument extends PlainDocument {
      public void insertString(int offs, String str, AttributeSet a)
         throws BadLocationException {

         if ( str == null ) return;
         str = str.trim();

         int length = getLength();
         String buf = getText(0,offs) + str + getText(offs,length-offs);
         buf = buf.trim();
         char[] array = buf.toCharArray();

         if ( array.length > 0 ) {
            if ( array[0] != MINUS && !member(array[0],numberSet) &&
	         array[0] != PERIOD ) {
               Toolkit.getDefaultToolkit().beep();
               return;
            }
         }

	 boolean period_found = (array.length > 0 && array[0] == PERIOD);

         for(int i = 1; i < array.length; i++ ) {
            if ( !member(array[i],numberSet) ) {
               if ( !period_found && array[i] == PERIOD ) {
                  period_found = true;
               }
               else {
	          Toolkit.getDefaultToolkit().beep();
                  return;
               }
            }
         }
         super.insertString(offs,str,a);
      }
   }
   static boolean member(char item, char[] array) {
      for(int i = 0; i < array.length; i++ )
         if ( array[i] == item ) return true;
      return false;
   }
   //------------------------------------------------------------------------
   // Event Methods
   //------------------------------------------------------------------------

   public void addChangeListener(ChangeListener x) {
      changeListeners.add(ChangeListener.class, x);
   }

   public void removeChangeListener(ChangeListener x) {
      changeListeners.remove(ChangeListener.class, x);
   }

   protected void fireChanged() {
      ChangeEvent c = new ChangeEvent(this);
      Object[] listeners = changeListeners.getListenerList();
      for(int i= listeners.length-2; i >= 0; i -=2) {
         if (listeners[i] == ChangeListener.class) {
            ChangeListener cl = (ChangeListener)listeners[i+1];
            cl.stateChanged(c);
         }
      }
   }
}