# Class JPasswordField

java.lang.Object
java.awt.Component
java.awt.Container
javax.swing.JComponent
javax.swing.text.JTextComponent
javax.swing.JTextField
javax.swing.JPasswordField

All Implemented Interfaces:
  `ImageObserver, MenuContainer, Serializable, Accessible, Scrollable, SwingConstants`

@JavaBean(description="Allows the editing of a line of text but doesn't show the characters.") public class JPasswordField extends JTextField
`JPasswordField` is a lightweight component that allows the editing of a single line of text where the view indicates something was typed, but does not show the original characters. You can find further information and examples in How to Use Text Fields, a section in The Java Tutorial.

`JPasswordField` is intended to be source-compatible with `java.awt.TextField` used with `echoChar` set. It is provided separately to make it easier to safely change the UI for the `JTextField` without affecting password entries.

NOTE: By default, JPasswordField disables input methods; otherwise, input characters could be visible while they were composed using input methods. If an application needs the input methods support, please use the inherited method, `enableInputMethods(true)`.

Warning: The `JPasswordField` will not show the original characters that were typed, instead displaying alternative text or graphics. However this doesn't prevent the password from appearing in the system memory. For handling confidential information such as the password text, refer to the relevant section at Secure Coding Guidelines.

Warning: Swing is not thread safe. For more information see Swing's Threading Policy.

Warning: Serialized objects of this class will not be compatible with future Swing releases. The current serialization support is appropriate for short term storage or RMI between applications running the same version of Swing. As of 1.4, support for long term storage of all JavaBeans has been added to the `java.beans` package. Please see `XMLEncoder`.

Since:
  1.2

- ## Nested Class Summary

  Nested Classes
  Modifier and Type
  Class
  Description
  `protected class`
  `JPasswordField.AccessibleJPasswordField`
  This class implements accessibility support for the `JPasswordField` class.

  ### Nested classes/interfaces declared in class JTextField

  `JTextField.AccessibleJTextField`

  ### Nested classes/interfaces declared in class JTextComponent

  `JTextComponent.AccessibleJTextComponent, JTextComponent.DropLocation, JTextComponent.KeyBinding`

  ### Nested classes/interfaces declared in class JComponent

  `JComponent.AccessibleJComponent`

  ### Nested classes/interfaces declared in class Container

  `Container.AccessibleAWTContainer`

  ### Nested classes/interfaces declared in class Component

  `Component.AccessibleAWTComponent, Component.BaselineResizeBehavior, Component.BltBufferStrategy, Component.FlipBufferStrategy`

- ## Field Summary

  ### Fields declared in class JTextField

  `notifyAction`

  ### Fields declared in class JTextComponent

  `DEFAULT_KEYMAP, FOCUS_ACCELERATOR_KEY`

  ### Fields declared in class JComponent

  `listenerList, TOOL_TIP_TEXT_KEY, ui, UNDEFINED_CONDITION, WHEN_ANCESTOR_OF_FOCUSED_COMPONENT, WHEN_FOCUSED, WHEN_IN_FOCUSED_WINDOW`

  ### Fields declared in class Component

  `accessibleContext, BOTTOM_ALIGNMENT, CENTER_ALIGNMENT, LEFT_ALIGNMENT, RIGHT_ALIGNMENT, TOP_ALIGNMENT`

  ### Fields declared in interface ImageObserver

  `ABORT, ALLBITS, ERROR, FRAMEBITS, HEIGHT, PROPERTIES, SOMEBITS, WIDTH`

  ### Fields declared in interface SwingConstants

  `BOTTOM, CENTER, EAST, HORIZONTAL, LEADING, LEFT, NEXT, NORTH, NORTH_EAST, NORTH_WEST, PREVIOUS, RIGHT, SOUTH, SOUTH_EAST, SOUTH_WEST, TOP, TRAILING, VERTICAL, WEST`

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `JPasswordField()`
  Constructs a new `JPasswordField`, with a default document, `null` starting text string, and 0 column width.
  `JPasswordField(int columns)`
  Constructs a new empty `JPasswordField` with the specified number of columns.
  `JPasswordField(String text)`
  Constructs a new `JPasswordField` initialized with the specified text.
  `JPasswordField(String text, int columns)`
  Constructs a new `JPasswordField` initialized with the specified text and columns.
  `JPasswordField(Document doc, String txt, int columns)`
  Constructs a new `JPasswordField` that uses the given text storage model and the given number of columns.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `copy()`
  Invokes `provideErrorFeedback` on the current look and feel, which typically initiates an error beep.
  `void`
  `cut()`
  Invokes `provideErrorFeedback` on the current look and feel, which typically initiates an error beep.
  `boolean`
  `echoCharIsSet()`
  Returns true if this `JPasswordField` has a character set for echoing.
  `AccessibleContext`
  `getAccessibleContext()`
  Returns the `AccessibleContext` associated with this `JPasswordField`.
  `char`
  `getEchoChar()`
  Returns the character to be used for echoing.
  `char[]`
  `getPassword()`
  Returns the text contained in this `TextComponent`.
  `String`
  `getText()`
  Deprecated.
  As of Java 2 platform v1.2, replaced by `getPassword`.
  `String`
  `getText(int offs, int len)`
  Deprecated.
  As of Java 2 platform v1.2, replaced by `getPassword`.
  `String`
  `getUIClassID()`
  Returns the name of the L&F class that renders this component.
  `protected String`
  `paramString()`
  Returns a string representation of this `JPasswordField`.
  `void`
  `setEchoChar(char c)`
  Sets the echo character for this `JPasswordField`.
  `void`
  `setText(String t)`
  Sets the text of this `TextComponent` to the specified text.
  `void`
  `updateUI()`
  Reloads the pluggable UI.

  ### Methods declared in class JTextField

  `actionPropertyChanged, addActionListener, configurePropertiesFromAction, createActionPropertyChangeListener, createDefaultModel, fireActionPerformed, getAction, getActionListeners, getActions, getColumns, getColumnWidth, getHorizontalAlignment, getHorizontalVisibility, getPreferredSize, getScrollOffset, isValidateRoot, postActionEvent, removeActionListener, scrollRectToVisible, setAction, setActionCommand, setColumns, setDocument, setFont, setHorizontalAlignment, setScrollOffset`

  ### Methods declared in class JTextComponent

  `addCaretListener, addKeymap, fireCaretUpdate, getCaret, getCaretColor, getCaretListeners, getCaretPosition, getDisabledTextColor, getDocument, getDragEnabled, getDropLocation, getDropMode, getFocusAccelerator, getHighlighter, getInputMethodRequests, getKeymap, getKeymap, getMargin, getNavigationFilter, getPreferredScrollableViewportSize, getPrintable, getScrollableBlockIncrement, getScrollableTracksViewportHeight, getScrollableTracksViewportWidth, getScrollableUnitIncrement, getSelectedText, getSelectedTextColor, getSelectionColor, getSelectionEnd, getSelectionStart, getToolTipText, getUI, isEditable, loadKeymap, modelToView, modelToView2D, moveCaretPosition, paste, print, print, print, read, removeCaretListener, removeKeymap, replaceSelection, restoreComposedText, saveComposedText, select, selectAll, setCaret, setCaretColor, setCaretPosition, setDisabledTextColor, setDragEnabled, setDropMode, setEditable, setFocusAccelerator, setHighlighter, setKeymap, setMargin, setNavigationFilter, setSelectedTextColor, setSelectionColor, setSelectionEnd, setSelectionStart, setUI, viewToModel, viewToModel2D, write`

  ### Methods declared in class JComponent

  `addAncestorListener, addNotify, addVetoableChangeListener, computeVisibleRect, contains, createToolTip, disable, enable, firePropertyChange, firePropertyChange, fireVetoableChange, getActionForKeyStroke, getActionMap, getAlignmentX, getAlignmentY, getAncestorListeners, getAutoscrolls, getBaseline, getBaselineResizeBehavior, getBorder, getBounds, getClientProperty, getComponentGraphics, getComponentPopupMenu, getConditionForKeyStroke, getDebugGraphicsOptions, getDefaultLocale, getFontMetrics, getGraphics, getHeight, getInheritsPopupMenu, getInputMap, getInputMap, getInputVerifier, getInsets, getInsets, getListeners, getLocation, getMaximumSize, getMinimumSize, getNextFocusableComponent, getPopupLocation, getRegisteredKeyStrokes, getRootPane, getSize, getToolTipLocation, getToolTipText, getTopLevelAncestor, getTransferHandler, getVerifyInputWhenFocusTarget, getVetoableChangeListeners, getVisibleRect, getWidth, getX, getY, grabFocus, hide, isDoubleBuffered, isLightweightComponent, isManagingFocus, isOpaque, isOptimizedDrawingEnabled, isPaintingForPrint, isPaintingOrigin, isPaintingTile, isRequestFocusEnabled, paint, paintBorder, paintChildren, paintComponent, paintImmediately, paintImmediately, print, printAll, printBorder, printChildren, printComponent, processComponentKeyEvent, processKeyBinding, processKeyEvent, processMouseEvent, processMouseMotionEvent, putClientProperty, registerKeyboardAction, registerKeyboardAction, removeAncestorListener, removeNotify, removeVetoableChangeListener, repaint, repaint, requestDefaultFocus, requestFocus, requestFocus, requestFocusInWindow, requestFocusInWindow, resetKeyboardActions, reshape, revalidate, setActionMap, setAlignmentX, setAlignmentY, setAutoscrolls, setBackground, setBorder, setComponentPopupMenu, setDebugGraphicsOptions, setDefaultLocale, setDoubleBuffered, setEnabled, setFocusTraversalKeys, setForeground, setInheritsPopupMenu, setInputMap, setInputVerifier, setMaximumSize, setMinimumSize, setNextFocusableComponent, setOpaque, setPreferredSize, setRequestFocusEnabled, setToolTipText, setTransferHandler, setUI, setVerifyInputWhenFocusTarget, setVisible, unregisterKeyboardAction, update`

  ### Methods declared in class Container

  `add, add, add, add, add, addContainerListener, addImpl, addPropertyChangeListener, addPropertyChangeListener, applyComponentOrientation, areFocusTraversalKeysSet, countComponents, deliverEvent, doLayout, findComponentAt, findComponentAt, getComponent, getComponentAt, getComponentAt, getComponentCount, getComponents, getComponentZOrder, getContainerListeners, getFocusTraversalKeys, getFocusTraversalPolicy, getLayout, getMousePosition, insets, invalidate, isAncestorOf, isFocusCycleRoot, isFocusCycleRoot, isFocusTraversalPolicyProvider, isFocusTraversalPolicySet, layout, list, list, locate, minimumSize, paintComponents, preferredSize, printComponents, processContainerEvent, processEvent, remove, remove, removeAll, removeContainerListener, setComponentZOrder, setFocusCycleRoot, setFocusTraversalPolicy, setFocusTraversalPolicyProvider, setLayout, transferFocusDownCycle, validate, validateTree`

  ### Methods declared in class Component

  `action, add, addComponentListener, addFocusListener, addHierarchyBoundsListener, addHierarchyListener, addInputMethodListener, addKeyListener, addMouseListener, addMouseMotionListener, addMouseWheelListener, bounds, checkImage, checkImage, coalesceEvents, contains, createImage, createImage, createVolatileImage, createVolatileImage, disableEvents, dispatchEvent, enable, enableEvents, enableInputMethods, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, firePropertyChange, getBackground, getBounds, getColorModel, getComponentListeners, getComponentOrientation, getCursor, getDropTarget, getFocusCycleRootAncestor, getFocusListeners, getFocusTraversalKeysEnabled, getFont, getForeground, getGraphicsConfiguration, getHierarchyBoundsListeners, getHierarchyListeners, getIgnoreRepaint, getInputContext, getInputMethodListeners, getKeyListeners, getLocale, getLocation, getLocationOnScreen, getMouseListeners, getMouseMotionListeners, getMousePosition, getMouseWheelListeners, getName, getParent, getPropertyChangeListeners, getPropertyChangeListeners, getSize, getToolkit, getTreeLock, gotFocus, handleEvent, hasFocus, imageUpdate, inside, isBackgroundSet, isCursorSet, isDisplayable, isEnabled, isFocusable, isFocusOwner, isFocusTraversable, isFontSet, isForegroundSet, isLightweight, isMaximumSizeSet, isMinimumSizeSet, isPreferredSizeSet, isShowing, isValid, isVisible, keyDown, keyUp, list, list, list, location, lostFocus, mouseDown, mouseDrag, mouseEnter, mouseExit, mouseMove, mouseUp, move, nextFocus, paintAll, postEvent, prepareImage, prepareImage, processComponentEvent, processFocusEvent, processHierarchyBoundsEvent, processHierarchyEvent, processInputMethodEvent, processMouseWheelEvent, remove, removeComponentListener, removeFocusListener, removeHierarchyBoundsListener, removeHierarchyListener, removeInputMethodListener, removeKeyListener, removeMouseListener, removeMouseMotionListener, removeMouseWheelListener, removePropertyChangeListener, removePropertyChangeListener, repaint, repaint, repaint, requestFocus, requestFocus, requestFocusInWindow, resize, resize, setBounds, setBounds, setComponentOrientation, setCursor, setDropTarget, setFocusable, setFocusTraversalKeysEnabled, setIgnoreRepaint, setLocale, setLocation, setLocation, setMixingCutoutShape, setName, setSize, setSize, show, show, size, toString, transferFocus, transferFocusBackward, transferFocusUpCycle`

  ### Methods declared in class Object

  `clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait`

- ## Constructor Details

  - ### JPasswordField

    public JPasswordField()
    Constructs a new `JPasswordField`, with a default document, `null` starting text string, and 0 column width.

  - ### JPasswordField

    public JPasswordField(String text)
    Constructs a new `JPasswordField` initialized with the specified text. The document model is set to the default, and the number of columns to 0.
    Parameters:
      `text` - the text to be displayed, `null` if none

  - ### JPasswordField

    public JPasswordField(int columns)
    Constructs a new empty `JPasswordField` with the specified number of columns. A default model is created, and the initial string is set to `null`.
    Parameters:
      `columns` - the number of columns >= 0

  - ### JPasswordField

    public JPasswordField(String text, int columns)
    Constructs a new `JPasswordField` initialized with the specified text and columns. The document model is set to the default.
    Parameters:
      `text` - the text to be displayed, `null` if none
      `columns` - the number of columns >= 0

  - ### JPasswordField

    public JPasswordField(Document doc, String txt, int columns)
    Constructs a new `JPasswordField` that uses the given text storage model and the given number of columns. This is the constructor through which the other constructors feed. The echo character is set to '*', but may be changed by the current Look and Feel. If the document model is `null`, a default one will be created.
    Parameters:
      `doc` - the text storage to use
      `txt` - the text to be displayed, `null` if none
      `columns` - the number of columns to use to calculate the preferred width >= 0; if columns is set to zero, the preferred width will be whatever naturally results from the component implementation

- ## Method Details

  - ### getUIClassID

    @BeanProperty(bound=false) public String getUIClassID()
    Returns the name of the L&F class that renders this component.
    Overrides:
      `getUIClassID` in class `JTextField`
    Returns:
      the string "PasswordFieldUI"
    See Also:
      - `JComponent.getUIClassID()`
      - `UIDefaults.getUI(JComponent)`

  - ### updateUI

    public void updateUI()
    Reloads the pluggable UI. The key used to fetch the new interface is `getUIClassID()`. The type of the UI is `TextUI`. `invalidate` is called after setting the UI.
    Overrides:
      `updateUI` in class `JTextComponent`
    Since:
      1.6
    See Also:
      - `JComponent.setUI(ComponentUI)`
      - `UIManager.getLookAndFeel()`
      - `UIManager.getUI(JComponent)`

  - ### getEchoChar

    public char getEchoChar()
    Returns the character to be used for echoing. The default is '*'. The default may be different depending on the currently running Look and Feel. For example, Metal/Ocean's default is a bullet character.
    Returns:
      the echo character, 0 if unset
    See Also:
      - `setEchoChar(char)`
      - `echoCharIsSet()`

  - ### setEchoChar

    @BeanProperty(bound=false, visualUpdate=true, description="character to display in place of the real characters") public void setEchoChar(char c)
    Sets the echo character for this `JPasswordField`. Note that this is largely a suggestion, since the view that gets installed can use whatever graphic techniques it desires to represent the field. Setting a value of 0 indicates that you wish to see the text as it is typed, similar to the behavior of a standard `JTextField`.
    Parameters:
      `c` - the echo character to display
    See Also:
      - `echoCharIsSet()`
      - `getEchoChar()`

  - ### echoCharIsSet

    public boolean echoCharIsSet()
    Returns true if this `JPasswordField` has a character set for echoing. A character is considered to be set if the echo character is not 0.
    Returns:
      true if a character is set for echoing
    See Also:
      - `setEchoChar(char)`
      - `getEchoChar()`

  - ### cut

    public void cut()
    Invokes `provideErrorFeedback` on the current look and feel, which typically initiates an error beep. The normal behavior of transferring the currently selected range in the associated text model to the system clipboard, and removing the contents from the model, is not acceptable for a password field.
    Overrides:
      `cut` in class `JTextComponent`
    See Also:
      - `Toolkit.getSystemClipboard()`
      - `Clipboard`

  - ### copy

    public void copy()
    Invokes `provideErrorFeedback` on the current look and feel, which typically initiates an error beep. The normal behavior of transferring the currently selected range in the associated text model to the system clipboard, and leaving the contents from the model, is not acceptable for a password field.
    Overrides:
      `copy` in class `JTextComponent`
    See Also:
      - `Toolkit.getSystemClipboard()`
      - `Clipboard`

  - ### getText

    @Deprecated public String getText()
    Deprecated.
    As of Java 2 platform v1.2, replaced by `getPassword`.
    Returns the text contained in this `TextComponent`. If the underlying document is `null`, will give a `NullPointerException`.

    For security reasons, this method is deprecated. Use the `* getPassword` method instead.

    Overrides:
      `getText` in class `JTextComponent`
    Returns:
      the text
    See Also:
      - `JTextComponent.setText(String)`

  - ### getText

    @Deprecated public String getText(int offs, int len) throws BadLocationException
    Deprecated.
    As of Java 2 platform v1.2, replaced by `getPassword`.
    Fetches a portion of the text represented by the component. Returns an empty string if length is 0.

    For security reasons, this method is deprecated. Use the `getPassword` method instead.

    Overrides:
      `getText` in class `JTextComponent`
    Parameters:
      `offs` - the offset >= 0
      `len` - the length >= 0
    Returns:
      the text
    Throws:
      `BadLocationException` - if the offset or length are invalid

  - ### setText

    @BeanProperty(bound=false, description="the text of this component") public void setText(String t)
    Description copied from class: `JTextComponent`
    Sets the text of this `TextComponent` to the specified text. If the text is `null` or empty, has the effect of simply deleting the old text. When text has been inserted, the resulting caret location is determined by the implementation of the caret class.

    Note that text is not a bound property, so no `PropertyChangeEvent` is fired when it changes. To listen for changes to the text, use `DocumentListener`.

    Overrides:
      `setText` in class `JTextComponent`
    Parameters:
      `t` - the new text to be set
    See Also:
      - `JTextComponent.getText(int, int)`
      - `DefaultCaret`

  - ### getPassword

    @BeanProperty(bound=false) public char[] getPassword()
    Returns the text contained in this `TextComponent`. If the underlying document is `null`, will give a `NullPointerException`. For stronger security, it is recommended that the returned character array be cleared after use by setting each character to zero.
    Returns:
      the text

  - ### paramString

    protected String paramString()
    Returns a string representation of this `JPasswordField`. 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`.
    Overrides:
      `paramString` in class `JTextField`
    Returns:
      a string representation of this `JPasswordField`

  - ### getAccessibleContext

    @BeanProperty(bound=false) public AccessibleContext getAccessibleContext()
    Returns the `AccessibleContext` associated with this `JPasswordField`. For password fields, the `AccessibleContext` takes the form of an `AccessibleJPasswordField`. A new `AccessibleJPasswordField` instance is created if necessary.
    Specified by:
      `getAccessibleContext` in interface `Accessible`
    Overrides:
      `getAccessibleContext` in class `JTextField`
    Returns:
      an `AccessibleJPasswordField` that serves as the `AccessibleContext` of this `JPasswordField`