/*
* @(#)TextField.java 1.65 06/10/10
*
* Copyright 1990-2008 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 only, as published by the Free Software Foundation.
*
* This program 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
* General Public License version 2 for more details (a copy is
* included at /legal/license.txt).
*
* You should have received a copy of the GNU General Public License
* version 2 along with this work; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 or visit www.sun.com if you need additional
* information or have any questions.
*
*/
package java.awt;
import sun.awt.peer.TextFieldPeer;
import sun.awt.PeerBasedToolkit;
import java.awt.event.*;
import java.io.ObjectOutputStream;
import java.io.ObjectInputStream;
import java.io.IOException;
import java.util.EventListener;
import java.awt.AWTEventMulticaster;
/**
* A <code>TextField</code> object is a text component
* that allows for the editing of a single line of text.
* <p>
* For example, the following image depicts a frame with four
* text fields of varying widths. Two of these text fields
* display the predefined text <code>"Hello"</code>.
* <p>
* <img src="images-awt/TextField-1.gif"
* ALIGN=center HSPACE=10 VSPACE=7>
* <p>
* Here is the code that produces these four text fields:
* <p>
* <hr><blockquote><pre>
* TextField tf1, tf2, tf3, tf4;
* // a blank text field
* tf1 = new TextField();
* // blank field of 20 columns
* tf2 = new TextField("", 20);
* // predefined text displayed
* tf3 = new TextField("Hello!");
* // predefined text in 30 columns
* tf4 = new TextField("Hello", 30);
* </pre></blockquote><hr>
* <p>
* Every time the user types a key in the text field, AWT
* sends two action events to the text field. The first
* one represents the key press and the second one,
* the key release. Each action event embodies the state
* of the system at the time that some action occurred.
* The properties of an action event indicate which
* key was pressed, what modifier keys were also pressed,
* and the time at which the event occurred.
* <p>
* Since the event is an instance of <code>ActionEvent</code>,
* the <code>TextField</code> class's <code>processEvent</code>
* method examines the event and passes it along to
* <code>processActionEvent</code>. The latter method redirects the
* event to any <code>ActionListener</code> objects that have
* registered an interest in action events generated by this
* text field.
*
* @version 1.59, 08/19/02
* @author Sami Shaio
* @see java.awt.event.ActionEvent
* @see java.awt.TextField#processEvent
* @see java.awt.TextField#processActionEvent
* @since JDK1.0
*/
public class TextField extends TextComponent {
/**
* The number of columns in the TextField.
*/
int columns;
/**
* The echo character.
*/
char echoChar;
transient ActionListener actionListener;
private static final String base = "textfield";
private static int nameCounter = 0;
/*
* JDK 1.1 serialVersionUID
*/
private static final long serialVersionUID = -2966288784432217853L;
/**
* Constructs a new text field.
* @since JDK1.0
*/
public TextField() {
this("", 0);
}
/**
* Constructs a new text field initialized with the specified text.
* @param text the text to be displayed.
* @since JDK1.0
*/
public TextField(String text) {
this(text, (text != null) ? text.length() : 0);
}
/**
* Constructs a new empty TextField with the specified number of columns.
* @param columns the number of columns
*/
public TextField(int columns) {
this("", columns);
}
/**
* Constructs a new text field initialized with the specified text
* to be displayed, and wide enough to hold the specified
* number of characters.
* @param text the text to be displayed.
* @param columns the number of characters.
* @since JDK1.0
*/
public TextField(String text, int columns) {
super(text);
this.columns = (columns >= 0) ? columns : 0;
}
/**
* Construct a name for this component. Called by getName() when the
* name is null.
*/
String constructComponentName() {
return base + nameCounter++;
}
/**
* Creates the TextField's peer. The peer allows us to modify the
* appearance of the TextField without changing its functionality.
*/
public void addNotify() {
synchronized (getTreeLock()) {
if (peer == null)
peer = ((PeerBasedToolkit) getToolkit()).createTextField(this);
super.addNotify();
}
}
/**
* Gets the character that is to be used for echoing.
* <p>
* An echo character is useful for text fields where
* user input should not be echoed to the screen, as in
* the case of a text field for entering a password.
* @return the echo character for this text field.
* @see java.awt.TextField#echoCharIsSet
* @see java.awt.TextField#setEchoChar
* @since JDK1.0
*/
public char getEchoChar() {
return echoChar;
}
/**
* Sets the echo character for this text field.
* <p>
* An echo character is useful for text fields where
* user input should not be echoed to the screen, as in
* the case of a text field for entering a password.
* @param c the echo character for this text field.
* @see java.awt.TextField#echoCharIsSet
* @see java.awt.TextField#getEchoChar
* @since JDK1.1
*/
public void setEchoChar(char c) {
setEchoCharacter(c);
}
/**
* @deprecated As of JDK version 1.1,
* replaced by <code>setEchoChar(char)</code>.
*/
public synchronized void setEchoCharacter(char c) {
if (echoChar != c) {
echoChar = c;
TextFieldPeer peer = (TextFieldPeer) this.peer;
if (peer != null) {
peer.setEchoChar(c);
}
}
}
/**
* Indicates whether or not this text field has a
* character set for echoing.
* <p>
* An echo character is useful for text fields where
* user input should not be echoed to the screen, as in
* the case of a text field for entering a password.
* @return <code>true</code> if this text field has
* a character set for echoing;
* <code>false</code> otherwise.
* @see java.awt.TextField#setEchoChar
* @see java.awt.TextField#getEchoChar
* @since JDK1.0
*/
public boolean echoCharIsSet() {
return echoChar != 0;
}
/**
* Gets the number of columns in this text field.
* @return the number of columns.
* @see java.awt.TextField#setColumns
* @since JDK1.1ld.
*/
public int getColumns() {
return columns;
}
/**
* Sets the number of columns in this text field.
* @param columns the number of columns.
* @see java.awt.TextField#getColumns
* @exception IllegalArgumentException if the value
* supplied for <code>columns</code>
* is less than zero.
* @since JDK1.1
*/
public synchronized void setColumns(int columns) {
int oldVal = this.columns;
if (columns < 0) {
throw new IllegalArgumentException("columns less than zero.");
}
if (columns != oldVal) {
this.columns = columns;
invalidate();
}
}
/**
* Gets the preferred size of this text field
* with the specified number of columns.
* @param columns the number of columns
* in this text field.
* @return the preferred dimensions for
* displaying this text field.
* @since JDK1.1
*/
public Dimension getPreferredSize(int columns) {
return preferredSize(columns);
}
/**
* @deprecated As of JDK version 1.1,
* replaced by <code>getPreferredSize(int)</code>.
*/
public Dimension preferredSize(int columns) {
synchronized (getTreeLock()) {
TextFieldPeer peer = (TextFieldPeer) this.peer;
return (peer != null) ?
peer.getPreferredSize(columns) :
super.preferredSize();
}
}
/**
* Gets the preferred size of this text field.
* @return the preferred dimensions for
* displaying this text field.
* @since JDK1.1
*/
public Dimension getPreferredSize() {
return preferredSize();
}
/**
* @deprecated As of JDK version 1.1,
* replaced by <code>getPreferredSize()</code>.
*/
public Dimension preferredSize() {
synchronized (getTreeLock()) {
return (columns > 0) ?
preferredSize(columns) :
super.preferredSize();
}
}
/**
* Gets the minumum dimensions for a text field with
* the specified number of columns.
* @param columns the number of columns in
* this text field.
* @since JDK1.1
*/
public Dimension getMinimumSize(int columns) {
return minimumSize(columns);
}
/**
* @deprecated As of JDK version 1.1,
* replaced by <code>getMinimumSize(int)</code>.
*/
public Dimension minimumSize(int columns) {
synchronized (getTreeLock()) {
TextFieldPeer peer = (TextFieldPeer) this.peer;
return (peer != null) ?
peer.getMinimumSize(columns) :
super.minimumSize();
}
}
/**
* Gets the minumum dimensions for this text field.
* @return the minimum dimensions for
* displaying this text field.
* @since JDK1.1
*/
public Dimension getMinimumSize() {
return minimumSize();
}
/**
* @deprecated As of JDK version 1.1,
* replaced by <code>getMinimumSize()</code>.
*/
public Dimension minimumSize() {
synchronized (getTreeLock()) {
return (columns > 0) ?
minimumSize(columns) :
super.minimumSize();
}
}
/**
* Adds the specified action listener to recieve
* action events from this text field.
* @param l the action listener.
* @see java.awt.event.ActionListener
* @see java.awt.TextField#removeActionListener
* @since JDK1.1
*/
public synchronized void addActionListener(ActionListener l) {
actionListener = AWTEventMulticaster.add(actionListener, l);
newEventsOnly = true;
}
/**
* Removes the specified action listener so that it no longer
* receives action events from this text field.
* @param l the action listener.
* @see java.awt.event.ActionListener
* @see java.awt.TextField#addActionListener
* @since JDK1.1
*/
public synchronized void removeActionListener(ActionListener l) {
actionListener = AWTEventMulticaster.remove(actionListener, l);
}
/**
* Returns an array of all the action listeners
* registered on this textfield.
*
* @return all of this textfield's <code>ActionListener</code>s
* or an empty array if no action
* listeners are currently registered
*
* @see #addActionListener
* @see #removeActionListener
* @see java.awt.event#ActionListener
* @since 1.4
*/
public synchronized ActionListener[] getActionListeners() {
return (ActionListener[])AWTEventMulticaster.getListeners(
(EventListener)actionListener,
ActionListener.class);
}
// NOTE remove when filtering is done at lower level
boolean eventEnabled(AWTEvent e) {
if (e.id == ActionEvent.ACTION_PERFORMED) {
if ((eventMask & AWTEvent.ACTION_EVENT_MASK) != 0 ||
actionListener != null) {
return true;
}
return false;
}
return super.eventEnabled(e);
}
/**
* Processes events on this text field. If the event
* is an instance of <code>ActionEvent</code>,
* it invokes the <code>processActionEvent</code>
* method. Otherwise, it invokes <code>processEvent</code>
* on the superclass.
* @param e the event.
* @see java.awt.event.ActionEvent
* @see java.awt.TextField#processActionEvent
* @since JDK1.1
*/
protected void processEvent(AWTEvent e) {
if (e instanceof ActionEvent) {
processActionEvent((ActionEvent) e);
return;
}
super.processEvent(e);
}
/**
* Processes action events occurring on this text field by
* dispatching them to any registered
* <code>ActionListener</code> objects.
* <p>
* This method is not called unless action events are
* enabled for this component. Action events are enabled
* when one of the following occurs:
* <p><ul>
* <li>An <code>ActionListener</code> object is registered
* via <code>addActionListener</code>.
* <li>Action events are enabled via <code>enableEvents</code>.
* </ul>
* @param e the action event.
* @see java.awt.event.ActionListener
* @see java.awt.TextField#addActionListener
* @see java.awt.Component#enableEvents
* @since JDK1.1
*/
protected void processActionEvent(ActionEvent e) {
if (actionListener != null) {
actionListener.actionPerformed(e);
}
}
/**
* Returns the parameter string representing the state of this
* text field. This string is useful for debugging.
* @return the parameter string of this text field.
* @since JDK1.0
*/
protected String paramString() {
String str = super.paramString();
if (echoChar != 0) {
str += ",echo=" + echoChar;
}
return str;
}
/* Serialization support.
*/
private int textFieldSerializedDataVersion = 1;
private void writeObject(ObjectOutputStream s)
throws IOException {
s.defaultWriteObject();
AWTEventMulticaster.save(s, actionListenerK, actionListener);
s.writeObject(null);
}
private void readObject(ObjectInputStream s)
throws ClassNotFoundException, IOException {
s.defaultReadObject();
Object keyOrNull;
while (null != (keyOrNull = s.readObject())) {
String key = ((String) keyOrNull).intern();
if (actionListenerK == key)
addActionListener((ActionListener) (s.readObject()));
else // skip value for unrecognized key
s.readObject();
}
}
}