/*
* Copyright (c) 1995, 2013, Oracle and/or its affiliates. All rights reserved.
* ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*
*
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*/
package java.awt;
import java.awt.peer.
TextFieldPeer;
import java.awt.event.*;
import java.util.
EventListener;
import java.io.
ObjectOutputStream;
import java.io.
ObjectInputStream;
import java.io.
IOException;
import javax.accessibility.*;
/**
* 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="doc-files/TextField-1.gif" alt="The preceding text describes this image."
* style="float:center; margin: 7px 10px;">
* <p>
* Here is the code that produces these four text fields:
*
* <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, one or
* more key events are sent to the text field. A <code>KeyEvent</code>
* may be one of three types: keyPressed, keyReleased, or keyTyped.
* The properties of a key event indicate which of these types
* it is, as well as additional information about the event,
* such as what modifiers are applied to the key event and the
* time at which the event occurred.
* <p>
* The key event is passed to every <code>KeyListener</code>
* or <code>KeyAdapter</code> object which registered to receive such
* events using the component's <code>addKeyListener</code> method.
* (<code>KeyAdapter</code> objects implement the
* <code>KeyListener</code> interface.)
* <p>
* It is also possible to fire an <code>ActionEvent</code>.
* If action events are enabled for the text field, they may
* be fired by pressing the <code>Return</code> key.
* <p>
* The <code>TextField</code> class's <code>processEvent</code>
* method examines the action event and passes it along to
* <code>processActionEvent</code>. The latter method redirects the
* event to any <code>ActionListener</code> objects that have
* registered to receive action events generated by this
* text field.
*
* @author Sami Shaio
* @see java.awt.event.KeyEvent
* @see java.awt.event.KeyAdapter
* @see java.awt.event.KeyListener
* @see java.awt.event.ActionEvent
* @see java.awt.Component#addKeyListener
* @see java.awt.TextField#processEvent
* @see java.awt.TextField#processActionEvent
* @see java.awt.TextField#addActionListener
* @since JDK1.0
*/
public class
TextField extends
TextComponent {
/**
* The number of columns in the text field.
* A column is an approximate average character
* width that is platform-dependent.
* Guaranteed to be non-negative.
*
* @serial
* @see #setColumns(int)
* @see #getColumns()
*/
int
columns;
/**
* The echo character, which is used when
* the user wishes to disguise the characters
* typed into the text field.
* The disguises are removed if echoChar = <code>0</code>.
*
* @serial
* @see #getEchoChar()
* @see #setEchoChar(char)
* @see #echoCharIsSet()
*/
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;
/**
* Initialize JNI field and method ids
*/
private static native void
initIDs();
static {
/* ensure that the necessary native libraries are loaded */
Toolkit.
loadLibraries();
if (!
GraphicsEnvironment.
isHeadless()) {
initIDs();
}
}
/**
* Constructs a new text field.
* @exception HeadlessException if GraphicsEnvironment.isHeadless()
* returns true.
* @see java.awt.GraphicsEnvironment#isHeadless
*/
public
TextField() throws
HeadlessException {
this("", 0);
}
/**
* Constructs a new text field initialized with the specified text.
* @param text the text to be displayed. If
* <code>text</code> is <code>null</code>, the empty
* string <code>""</code> will be displayed.
* @exception HeadlessException if GraphicsEnvironment.isHeadless()
* returns true.
* @see java.awt.GraphicsEnvironment#isHeadless
*/
public
TextField(
String text) throws
HeadlessException {
this(
text, (
text != null) ?
text.
length() : 0);
}
/**
* Constructs a new empty text field with the specified number
* of columns. A column is an approximate average character
* width that is platform-dependent.
* @param columns the number of columns. If
* <code>columns</code> is less than <code>0</code>,
* <code>columns</code> is set to <code>0</code>.
* @exception HeadlessException if GraphicsEnvironment.isHeadless()
* returns true.
* @see java.awt.GraphicsEnvironment#isHeadless
*/
public
TextField(int
columns) throws
HeadlessException {
this("",
columns);
}
/**
* Constructs a new text field initialized with the specified text
* to be displayed, and wide enough to hold the specified
* number of columns. A column is an approximate average character
* width that is platform-dependent.
* @param text the text to be displayed. If
* <code>text</code> is <code>null</code>, the empty
* string <code>""</code> will be displayed.
* @param columns the number of columns. If
* <code>columns</code> is less than <code>0</code>,
* <code>columns</code> is set to <code>0</code>.
* @exception HeadlessException if GraphicsEnvironment.isHeadless()
* returns true.
* @see java.awt.GraphicsEnvironment#isHeadless
*/
public
TextField(
String text, int
columns) throws
HeadlessException {
super(
text);
this.
columns = (
columns >= 0) ?
columns : 0;
}
/**
* Construct a name for this component. Called by getName() when the
* name is null.
*/
String constructComponentName() {
synchronized (
TextField.class) {
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 =
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.
* If <code>echoChar</code> = <code>0</code>, user
* input is echoed to the screen unchanged.
* <p>
* A Java platform implementation may support only a limited,
* non-empty set of echo characters. This function returns the
* echo character originally requested via setEchoChar(). The echo
* character actually used by the TextField implementation might be
* different.
* @return the echo character for this text field.
* @see java.awt.TextField#echoCharIsSet
* @see java.awt.TextField#setEchoChar
*/
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.
* Setting <code>echoChar</code> = <code>0</code> allows
* user input to be echoed to the screen again.
* <p>
* A Java platform implementation may support only a limited,
* non-empty set of echo characters. Attempts to set an
* unsupported echo character will cause the default echo
* character to be used instead. Subsequent calls to getEchoChar()
* will return the echo character originally requested. This might
* or might not be identical to the echo character actually
* used by the TextField implementation.
* @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>.
*/
@
Deprecated
public synchronized void
setEchoCharacter(char
c) {
if (
echoChar !=
c) {
echoChar =
c;
TextFieldPeer peer = (
TextFieldPeer)this.
peer;
if (
peer != null) {
peer.
setEchoChar(
c);
}
}
}
/**
* Sets the text that is presented by this
* text component to be the specified text.
* @param t the new text.
* @see java.awt.TextComponent#getText
*/
public void
setText(
String t) {
super.setText(
t);
// This could change the preferred size of the Component.
invalidateIfValid();
}
/**
* 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
*/
public boolean
echoCharIsSet() {
return
echoChar != 0;
}
/**
* Gets the number of columns in this text field. A column is an
* approximate average character width that is platform-dependent.
* @return the number of columns.
* @see java.awt.TextField#setColumns
* @since JDK1.1
*/
public int
getColumns() {
return
columns;
}
/**
* Sets the number of columns in this text field. A column is an
* approximate average character width that is platform-dependent.
* @param columns the number of columns.
* @see java.awt.TextField#getColumns
* @exception IllegalArgumentException if the value
* supplied for <code>columns</code>
* is less than <code>0</code>.
* @since JDK1.1
*/
public void
setColumns(int
columns) {
int
oldVal;
synchronized (this) {
oldVal = this.
columns;
if (
columns < 0) {
throw new
IllegalArgumentException("columns less than zero.");
}
if (
columns !=
oldVal) {
this.
columns =
columns;
}
}
if (
columns !=
oldVal) {
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>.
*/
@
Deprecated
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>.
*/
@
Deprecated
public
Dimension preferredSize() {
synchronized (
getTreeLock()) {
return (
columns > 0) ?
preferredSize(
columns) :
super.preferredSize();
}
}
/**
* Gets the minimum 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>.
*/
@
Deprecated
public
Dimension minimumSize(int
columns) {
synchronized (
getTreeLock()) {
TextFieldPeer peer = (
TextFieldPeer)this.
peer;
return (
peer != null) ?
peer.
getMinimumSize(
columns) :
super.minimumSize();
}
}
/**
* Gets the minimum 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>.
*/
@
Deprecated
public
Dimension minimumSize() {
synchronized (
getTreeLock()) {
return (
columns > 0) ?
minimumSize(
columns) :
super.minimumSize();
}
}
/**
* Adds the specified action listener to receive
* action events from this text field.
* If l is null, no exception is thrown and no action is performed.
* <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
* >AWT Threading Issues</a> for details on AWT's threading model.
*
* @param l the action listener.
* @see #removeActionListener
* @see #getActionListeners
* @see java.awt.event.ActionListener
* @since JDK1.1
*/
public synchronized void
addActionListener(
ActionListener l) {
if (
l == null) {
return;
}
actionListener =
AWTEventMulticaster.
add(
actionListener,
l);
newEventsOnly = true;
}
/**
* Removes the specified action listener so that it no longer
* receives action events from this text field.
* If l is null, no exception is thrown and no action is performed.
* <p>Refer to <a href="doc-files/AWTThreadIssues.html#ListenersThreads"
* >AWT Threading Issues</a> for details on AWT's threading model.
*
* @param l the action listener.
* @see #addActionListener
* @see #getActionListeners
* @see java.awt.event.ActionListener
* @since JDK1.1
*/
public synchronized void
removeActionListener(
ActionListener l) {
if (
l == null) {
return;
}
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
getListeners(
ActionListener.class);
}
/**
* Returns an array of all the objects currently registered
* as <code><em>Foo</em>Listener</code>s
* upon this <code>TextField</code>.
* <code><em>Foo</em>Listener</code>s are registered using the
* <code>add<em>Foo</em>Listener</code> method.
*
* <p>
* You can specify the <code>listenerType</code> argument
* with a class literal, such as
* <code><em>Foo</em>Listener.class</code>.
* For example, you can query a
* <code>TextField</code> <code>t</code>
* for its action listeners with the following code:
*
* <pre>ActionListener[] als = (ActionListener[])(t.getListeners(ActionListener.class));</pre>
*
* If no such listeners exist, this method returns an empty array.
*
* @param listenerType the type of listeners requested; this parameter
* should specify an interface that descends from
* <code>java.util.EventListener</code>
* @return an array of all objects registered as
* <code><em>Foo</em>Listener</code>s on this textfield,
* or an empty array if no such
* listeners have been added
* @exception ClassCastException if <code>listenerType</code>
* doesn't specify a class or interface that implements
* <code>java.util.EventListener</code>
*
* @see #getActionListeners
* @since 1.3
*/
public <T extends
EventListener> T[]
getListeners(
Class<T>
listenerType) {
EventListener l = null;
if (
listenerType ==
ActionListener.class) {
l =
actionListener;
} else {
return super.getListeners(
listenerType);
}
return
AWTEventMulticaster.
getListeners(
l,
listenerType);
}
// REMIND: 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.
* <p>Note that if the event parameter is <code>null</code>
* the behavior is unspecified and may result in an
* exception.
*
* @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:
* <ul>
* <li>An <code>ActionListener</code> object is registered
* via <code>addActionListener</code>.
* <li>Action events are enabled via <code>enableEvents</code>.
* </ul>
* <p>Note that if the event parameter is <code>null</code>
* the behavior is unspecified and may result in an
* exception.
*
* @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) {
ActionListener listener =
actionListener;
if (
listener != null) {
listener.
actionPerformed(
e);
}
}
/**
* Returns a string representing the state of this <code>TextField</code>.
* This method is intended to be used only for debugging purposes, and the
* content and format of the returned string may vary between
* implementations. The returned string may be empty but may not be
* <code>null</code>.
*
* @return the parameter string of this text field
*/
protected
String paramString() {
String str = super.paramString();
if (
echoChar != 0) {
str += ",echo=" +
echoChar;
}
return
str;
}
/*
* Serialization support.
*/
/**
* The textField Serialized Data Version.
*
* @serial
*/
private int
textFieldSerializedDataVersion = 1;
/**
* Writes default serializable fields to stream. Writes
* a list of serializable ActionListener(s) as optional data.
* The non-serializable ActionListener(s) are detected and
* no attempt is made to serialize them.
*
* @serialData Null terminated sequence of zero or more pairs.
* A pair consists of a String and Object.
* The String indicates the type of object and
* is one of the following :
* ActionListenerK indicating and ActionListener object.
*
* @see AWTEventMulticaster#save(ObjectOutputStream, String, EventListener)
* @see java.awt.Component#actionListenerK
*/
private void
writeObject(
ObjectOutputStream s)
throws
IOException
{
s.
defaultWriteObject();
AWTEventMulticaster.
save(
s,
actionListenerK,
actionListener);
s.
writeObject(null);
}
/**
* Read the ObjectInputStream and if it isn't null,
* add a listener to receive action events fired by the
* TextField. Unrecognized keys or values will be
* ignored.
*
* @exception HeadlessException if
* <code>GraphicsEnvironment.isHeadless()</code> returns
* <code>true</code>
* @see #removeActionListener(ActionListener)
* @see #addActionListener(ActionListener)
* @see java.awt.GraphicsEnvironment#isHeadless
*/
private void
readObject(
ObjectInputStream s)
throws
ClassNotFoundException,
IOException,
HeadlessException
{
// HeadlessException will be thrown by TextComponent's readObject
s.
defaultReadObject();
// Make sure the state we just read in for columns has legal values
if (
columns < 0) {
columns = 0;
}
// Read in listeners, if any
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();
}
}
}
/////////////////
// Accessibility support
////////////////
/**
* Gets the AccessibleContext associated with this TextField.
* For text fields, the AccessibleContext takes the form of an
* AccessibleAWTTextField.
* A new AccessibleAWTTextField instance is created if necessary.
*
* @return an AccessibleAWTTextField that serves as the
* AccessibleContext of this TextField
* @since 1.3
*/
public
AccessibleContext getAccessibleContext() {
if (
accessibleContext == null) {
accessibleContext = new
AccessibleAWTTextField();
}
return
accessibleContext;
}
/**
* This class implements accessibility support for the
* <code>TextField</code> class. It provides an implementation of the
* Java Accessibility API appropriate to text field user-interface elements.
* @since 1.3
*/
protected class
AccessibleAWTTextField extends
AccessibleAWTTextComponent
{
/*
* JDK 1.3 serialVersionUID
*/
private static final long
serialVersionUID = 6219164359235943158L;
/**
* Gets the state set of this object.
*
* @return an instance of AccessibleStateSet describing the states
* of the object
* @see AccessibleState
*/
public
AccessibleStateSet getAccessibleStateSet() {
AccessibleStateSet states = super.getAccessibleStateSet();
states.
add(
AccessibleState.
SINGLE_LINE);
return
states;
}
}
}