Also see:

setColumns(int)
getColumns()
serial:

Also see:

getEchoChar()
setEchoChar(char)
echoCharIsSet()
serial:

 public TextField() throws HeadlessException 
{
               
        /* ensure that the necessary native libraries are loaded */
        Toolkit.loadLibraries();
        if (!GraphicsEnvironment.isHeadless()) {
            initIDs();
        }
        this("", 0);
}

Constructs a new text field.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true.

Also see:

java.awt.GraphicsEnvironment#isHeadless
exception: HeadlessException - if GraphicsEnvironment.isHeadless() returns true.

 public TextField(String text) throws HeadlessException 
{
        this(text, (text != null) ? text.length() : 0);
}

Constructs a new text field initialized with the specified text.

Parameters:

text - the text to be displayed. If text is null, the empty string "" will be displayed.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true.

Also see:

java.awt.GraphicsEnvironment#isHeadless
exception: HeadlessException - if GraphicsEnvironment.isHeadless() returns true.

 public TextField(int columns) throws HeadlessException 
{
        this("", columns);
}

Constructs a new empty text field with the specified number of columns. A column is an approximate average character width that is platform-dependent.

Parameters:

columns - the number of columns. If columns is less than 0, columns is set to 0.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true.

Also see:

java.awt.GraphicsEnvironment#isHeadless
exception: HeadlessException - if GraphicsEnvironment.isHeadless() returns true.

 public TextField(String text,
    int columns) throws HeadlessException 
{
        super(text);
        this.columns = (columns  >= 0) ? columns : 0;
}

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.

Parameters:

text - the text to be displayed. If text is null, the empty string "" will be displayed.

columns - the number of columns. If columns is less than 0, columns is set to 0.

Throws:

HeadlessException - if GraphicsEnvironment.isHeadless() returns true.

Also see:

java.awt.GraphicsEnvironment#isHeadless
exception: HeadlessException - if GraphicsEnvironment.isHeadless() returns true.

 public synchronized  void addActionListener(ActionListener l) 
{
        if (l == null) {
            return;
        }
        actionListener = AWTEventMulticaster.add(actionListener, l);
        newEventsOnly = true;
}

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.

Refer to AWT Threading Issues for details on AWT's threading model.

 public  void addNotify() 
{
        synchronized (getTreeLock()) {
            if (peer == null)
                peer = getToolkit().createTextField(this);
            super.addNotify();
        }
}

Creates the TextField's peer. The peer allows us to modify the appearance of the TextField without changing its functionality.

 String constructComponentName() 
{
        synchronized (TextField.class) {
            return base + nameCounter++;
        }
}

Construct a name for this component. Called by getName() when the name is null.

 public boolean echoCharIsSet() 
{
        return echoChar != 0;
}

Indicates whether or not this text field has a character set for echoing.

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.

 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);
}

 public AccessibleContext getAccessibleContext() 
{
        if (accessibleContext == null) {
            accessibleContext = new AccessibleAWTTextField();
        }
        return accessibleContext;
}

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.

 public synchronized ActionListener[] getActionListeners() 
{
        return (ActionListener[])(getListeners(ActionListener.class));
}

Returns an array of all the action listeners registered on this textfield.

 public int getColumns() 
{
        return columns;
}

Gets the number of columns in this text field. A column is an approximate average character width that is platform-dependent.

 public char getEchoChar() 
{
        return echoChar;
}

Gets the character that is to be used for echoing.

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 echoChar = 0, user input is echoed to the screen unchanged.

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.

 public T[] getListeners(Class listenerType) 
{
        EventListener l = null;
        if  (listenerType == ActionListener.class) {
            l = actionListener;
        } else {
            return super.getListeners(listenerType);
        }
        return AWTEventMulticaster.getListeners(l, listenerType);
}

Returns an array of all the objects currently registered as FooListeners upon this TextField. FooListeners are registered using the addFooListener method.

You can specify the listenerType argument with a class literal, such as FooListener.class. For example, you can query a TextField t for its action listeners with the following code:

ActionListener[] als = (ActionListener[])(t.getListeners(ActionListener.class));

If no such listeners exist, this method returns an empty array.

 public Dimension getMinimumSize() 
{
        return minimumSize();
}

Gets the minumum dimensions for this text field.

 public Dimension getMinimumSize(int columns) 
{
        return minimumSize(columns);
}

Gets the minumum dimensions for a text field with the specified number of columns.

 public Dimension getPreferredSize() 
{
        return preferredSize();
}

Gets the preferred size of this text field.

 public Dimension getPreferredSize(int columns) 
{
        return preferredSize(columns);
}

Gets the preferred size of this text field with the specified number of columns.

 public Dimension minimumSize() 
{
        synchronized (getTreeLock()) {
            return (columns  > 0) ?
                       minimumSize(columns) :
                       super.minimumSize();
        }
}

 public Dimension minimumSize(int columns) 
{
        synchronized (getTreeLock()) {
            TextFieldPeer peer = (TextFieldPeer)this.peer;
            return (peer != null) ?
                       peer.minimumSize(columns) :
                       super.minimumSize();
        }
}

 protected String paramString() 
{
        String str = super.paramString();
        if (echoChar != 0) {
            str += ",echo=" + echoChar;
        }
        return str;
}

Returns a string representing the state of this TextField. 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 null.

 public Dimension preferredSize() 
{
        synchronized (getTreeLock()) {
            return (columns  > 0) ?
                       preferredSize(columns) :
                       super.preferredSize();
        }
}

 public Dimension preferredSize(int columns) 
{
        synchronized (getTreeLock()) {
            TextFieldPeer peer = (TextFieldPeer)this.peer;
            return (peer != null) ?
                       peer.preferredSize(columns) :
                       super.preferredSize();
        }
}

 protected  void processActionEvent(ActionEvent e) 
{
        ActionListener listener = actionListener;
        if (listener != null) {
            listener.actionPerformed(e);
        }
}

Processes action events occurring on this text field by dispatching them to any registered ActionListener objects.

This method is not called unless action events are enabled for this component. Action events are enabled when one of the following occurs:

• An ActionListener object is registered via addActionListener.
• Action events are enabled via enableEvents.

Note that if the event parameter is null the behavior is unspecified and may result in an exception.

 protected  void processEvent(AWTEvent e) 
{
        if (e instanceof ActionEvent) {
            processActionEvent((ActionEvent)e);
            return;
        }
        super.processEvent(e);
}

Processes events on this text field. If the event is an instance of ActionEvent, it invokes the processActionEvent method. Otherwise, it invokes processEvent on the superclass.

Note that if the event parameter is null the behavior is unspecified and may result in an exception.

 public synchronized  void removeActionListener(ActionListener l) 
{
        if (l == null) {
            return;
        }
        actionListener = AWTEventMulticaster.remove(actionListener, l);
}

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.

Refer to AWT Threading Issues for details on AWT's threading model.

 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();
        }
}

Sets the number of columns in this text field. A column is an approximate average character width that is platform-dependent.

 public  void setEchoChar(char c) 
{
        setEchoCharacter(c);
}

Sets the echo character for this text field.

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 echoChar = 0 allows user input to be echoed to the screen again.

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.

 public synchronized  void setEchoCharacter(char c) 
{
        if (echoChar != c) {
            echoChar = c;
            TextFieldPeer peer = (TextFieldPeer)this.peer;
            if (peer != null) {
                peer.setEchoCharacter(c);
            }
        }
}

 public  void setText(String t) 
{
        super.setText(t);
        // This could change the preferred size of the Component.
        if (valid) {
            invalidate();
        }
}

Sets the text that is presented by this text component to be the specified text.