libjava/classpath/javax/swing/JPasswordField.java

   1 /* JPasswordField.java --
   2    Copyright (C) 2002, 2004 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 javax.swing;
  40
  41 import java.io.IOException;
  42 import java.io.ObjectOutputStream;
  43
  44 import javax.accessibility.AccessibleContext;
  45 import javax.accessibility.AccessibleRole;
  46 import javax.swing.text.BadLocationException;
  47 import javax.swing.text.Document;
  48
  49 /**
  50  * class JPasswordField
  51  *
  52  * @author Andrew Selkirk
  53  * @author Lillian Angel
  54  * @version 1.0
  55  */
  56 public class JPasswordField extends JTextField
  57 {
  58   /**
  59    * AccessibleJPasswordField
  60    */
  61   protected class AccessibleJPasswordField extends AccessibleJTextField
  62   {
  63     private static final long serialVersionUID = -8477039424200681086L;
  64
  65     /**
  66      * Constructor AccessibleJPasswordField
  67      */
  68     protected AccessibleJPasswordField()
  69     {
  70       // Nothing to do here.
  71     }
  72
  73     /**
  74      * getAccessibleRole
  75      *
  76      * @return AccessibleRole
  77      */
  78     public AccessibleRole getAccessibleRole()
  79     {
  80       return AccessibleRole.PASSWORD_TEXT;
  81     }
  82   }
  83
  84   /**
  85    * echoChar.  Default is 0.
  86    */
  87   private char echoChar = 0;
  88
  89   /**
  90    * Creates a <code>JPasswordField</code> object.
  91    */
  92   public JPasswordField()
  93   {
  94     this(null, null, 0);
  95   }
  96
  97   /**
  98    * Creates a <code>JPasswordField</code> object.
  99    *
 100    * @param text the initial text
 101    */
 102   public JPasswordField(String text)
 103   {
 104     this(null, text, 0);
 105   }
 106
 107   /**
 108    * Creates a <code>JPasswordField</code> object.
 109    *
 110    * @param columns the number of columns
 111    */
 112   public JPasswordField(int columns)
 113   {
 114     this(null, null, columns);
 115   }
 116
 117   /**
 118    * Creates a <code>JPasswordField</code> object.
 119    *
 120    * @param text the initial text
 121    * @param columns the number of columns
 122    */
 123   public JPasswordField(String text, int columns)
 124   {
 125     this(null, text, columns);
 126   }
 127
 128   /**
 129    * Creates a <code>JPasswordField</code> object.
 130    *
 131    * @param document the document to use
 132    * @param text the initial text
 133    * @param columns the number of columns
 134    */
 135   public JPasswordField(Document document, String text, int columns)
 136   {
 137     super(document, text, columns);
 138   }
 139
 140   /**
 141    * writeObject
 142    *
 143    * @param stream the stream to write to
 144    *
 145    * @exception IOException if an error occurs
 146    */
 147   private void writeObject(ObjectOutputStream stream) throws IOException
 148   {
 149     // TODO: Implement me.
 150   }
 151
 152   /**
 153    * Returns the <code>UIClassID</code>
 154    *
 155    * @return the string "PasswordFieldUI"
 156    */
 157   public String getUIClassID()
 158   {
 159     return "PasswordFieldUI";
 160   }
 161
 162   /**
 163    * getEchoChar
 164    *
 165    * @return the echo char
 166    */
 167   public char getEchoChar()
 168   {
 169     return echoChar;
 170   }
 171
 172   /**
 173    * setEchoChar
 174    *
 175    * @param echo the echo char
 176    */
 177   public void setEchoChar(char echo)
 178   {
 179     this.echoChar = echo;
 180   }
 181
 182   /**
 183    * Returns true if this JPasswordField has a character set for echoing.
 184    * A character is considered to be set if the echo character is not 0.
 185    *
 186    * @return <code>true</code> if the echo char is set,
 187    * <code>false</code> otherwise.
 188    */
 189   public boolean echoCharIsSet()
 190   {
 191     return echoChar != 0;
 192   }
 193
 194   /**
 195    * Copies the selected text into the clipboard. This operation is not
 196    * allowed in a password input field.
 197    */
 198   public void copy()
 199   {
 200     UIManager.getLookAndFeel().provideErrorFeedback(this);
 201   }
 202
 203   /**
 204    * Cuts the selected text and puts it into the clipboard. This operation
 205    * is not allowed in a password input field.
 206    */
 207   public void cut()
 208   {
 209     UIManager.getLookAndFeel().provideErrorFeedback(this);
 210   }
 211
 212   /**
 213    * Returns the text contained in this TextComponent. If the
 214    * underlying document is null, will give a NullPointerException.
 215    *
 216    * @return String
 217    *
 218    * @deprecated
 219    */
 220   public String getText()
 221   {
 222     try
 223       {
 224         return getDocument().getText(0, getDocument().getLength());
 225       }
 226     catch (BadLocationException ble)
 227       {
 228         // This should never happen.
 229         throw new AssertionError(ble);
 230       }
 231   }
 232
 233   /**
 234    * Fetches a portion of the text represented by the component.
 235    * Returns an empty string if length is 0. If the
 236    * underlying document is null, will give a NullPointerException.
 237    *
 238    * @param offset TODO
 239    * @param length TODO
 240    *
 241    * @return String
 242    *
 243    * @exception BadLocationException TODO
 244    *
 245    * @deprecated
 246    */
 247   public String getText(int offset, int length) throws BadLocationException
 248   {
 249     return getDocument().getText(offset, length);
 250   }
 251
 252   /**
 253    * Returns the text contained in this TextComponent. If the underlying
 254    * document is null, will give a NullPointerException.
 255    * For stronger security, it is recommended that the returned character
 256    * array be cleared after use by setting each character to zero.
 257    *
 258    * @return char[]
 259    */
 260   public char[] getPassword()
 261   {
 262     return getText().toCharArray();
 263   }
 264
 265   /**
 266    * Returns a string representation of this JPasswordField. This method is
 267    * intended to be used only for debugging purposes,
 268    * and the content and format of the returned string may vary between
 269    * implementations. The returned string may be empty but may not be null.
 270    *
 271    * @return String
 272    */
 273   protected String paramString()
 274   {
 275     try
 276       {
 277         return getText();
 278       }
 279     catch (NullPointerException npe)
 280       {
 281         return "";
 282       }
 283   }
 284
 285   /**
 286    * getAccessibleContext
 287    *
 288    * @return the <code>AccessibleContext</code> object
 289    */
 290   public AccessibleContext getAccessibleContext()
 291   {
 292     if (accessibleContext == null)
 293       accessibleContext = new AccessibleJPasswordField();
 294
 295     return accessibleContext;
 296   }
 297 }