Java javax.swing Class JPasswordField（JDK8）

Constructor Detail

• 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 Detail

• getUIClassID

  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(javax.swing.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(javax.swing.plaf.ComponentUI), UIManager.getLookAndFeel(), UIManager.getUI(javax.swing.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

  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(java.lang.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

  public void setText(String t)

  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:

  getText(), DefaultCaret

• getPassword

  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

  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