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package javax.swing.text;

import sun.swing.SwingUtilities2;
import java.awt.*;
import java.awt.font.FontRenderContext;
import javax.swing.JPasswordField;


Implements a View suitable for use in JPasswordField
UI implementations.  This is basically a field ui that
renders its contents as the echo character specified
in the associated component (if it can narrow the
component to a JPasswordField).

Author: Timothy Prinzing
See Also:
/**
 * Implements a View suitable for use in JPasswordField
 * UI implementations.  This is basically a field ui that
 * renders its contents as the echo character specified
 * in the associated component (if it can narrow the
 * component to a JPasswordField).
 *
 * @author  Timothy Prinzing
 * @see     View
 */
public class PasswordView extends FieldView {

    
Constructs a new view wrapped on an element.

Params:
  • elem – the element
/**
     * Constructs a new view wrapped on an element.
     *
     * @param elem the element
     */
    public PasswordView(Element elem) {
        super(elem);
    }

    
Renders the given range in the model as normal unselected
text.  This sets the foreground color and echos the characters
using the value returned by getEchoChar().

Params:
  • g – the graphics context
  • x – the starting X coordinate >= 0
  • y – the starting Y coordinate >= 0
  • p0 – the starting offset in the model >= 0
  • p1 – the ending offset in the model >= p0
Throws:
Returns:the X location of the end of the range >= 0
Deprecated:replaced by drawUnselectedText(Graphics2D, float, float, int, int)
/**
     * Renders the given range in the model as normal unselected
     * text.  This sets the foreground color and echos the characters
     * using the value returned by getEchoChar().
     *
     * @param g the graphics context
     * @param x the starting X coordinate >= 0
     * @param y the starting Y coordinate >= 0
     * @param p0 the starting offset in the model >= 0
     * @param p1 the ending offset in the model >= p0
     * @return the X location of the end of the range >= 0
     * @exception BadLocationException if p0 or p1 are out of range
     *
     * @deprecated replaced by
     *     {@link #drawUnselectedText(Graphics2D, float, float, int, int)}
     */
    @Deprecated(since = "9")
    @Override
    protected int drawUnselectedText(Graphics g, int x, int y,
                                     int p0, int p1) throws BadLocationException {
        return (int) drawUnselectedTextImpl(g, x, y, p0, p1, false);
    }

    @Override
    protected float drawUnselectedText(Graphics2D g, float x, float y,
                                       int p0, int p1)
            throws BadLocationException
    {
        return drawUnselectedTextImpl(g, x, y, p0, p1, true);
    }

    @SuppressWarnings("deprecation")
    private float drawUnselectedTextImpl(Graphics g, float x, float y,
                                         int p0, int p1,
                                         boolean useFPAPI)
            throws BadLocationException
    {
        Container c = getContainer();
        if (c instanceof JPasswordField) {
            JPasswordField f = (JPasswordField) c;
            if (!f.echoCharIsSet()) {
                boolean useDrawUnselectedFPAPI = useFPAPI
                        && drawUnselectedTextOverridden
                        && g instanceof Graphics2D;
                return (useDrawUnselectedFPAPI )
                        ? super.drawUnselectedText((Graphics2D) g, x, y, p0, p1)
                        : super.drawUnselectedText(g, (int) x, (int) y, p0, p1);
            }
            if (f.isEnabled()) {
                g.setColor(f.getForeground());
            }
            else {
                g.setColor(f.getDisabledTextColor());
            }
            char echoChar = f.getEchoChar();
            int n = p1 - p0;
            boolean useEchoCharFPAPI = useFPAPI
                    && drawEchoCharacterOverridden
                    && g instanceof Graphics2D;
            for (int i = 0; i < n; i++) {
                x = (useEchoCharFPAPI)
                        ? drawEchoCharacter((Graphics2D) g, x, y, echoChar)
                        : drawEchoCharacter(g, (int) x, (int) y, echoChar);
            }
        }
        return x;
    }

    
Renders the given range in the model as selected text.  This
is implemented to render the text in the color specified in
the hosting component.  It assumes the highlighter will render
the selected background.  Uses the result of getEchoChar() to
display the characters.

Params:
  • g – the graphics context
  • x – the starting X coordinate >= 0
  • y – the starting Y coordinate >= 0
  • p0 – the starting offset in the model >= 0
  • p1 – the ending offset in the model >= p0
Throws:
Returns:the X location of the end of the range >= 0
Deprecated:replaced by drawSelectedText(Graphics2D, float, float, int, int)
/**
     * Renders the given range in the model as selected text.  This
     * is implemented to render the text in the color specified in
     * the hosting component.  It assumes the highlighter will render
     * the selected background.  Uses the result of getEchoChar() to
     * display the characters.
     *
     * @param g the graphics context
     * @param x the starting X coordinate &gt;= 0
     * @param y the starting Y coordinate &gt;= 0
     * @param p0 the starting offset in the model &gt;= 0
     * @param p1 the ending offset in the model &gt;= p0
     * @return the X location of the end of the range &gt;= 0
     * @exception BadLocationException if p0 or p1 are out of range
     *
     * @deprecated replaced by
     *     {@link #drawSelectedText(Graphics2D, float, float, int, int)}
     */
    @Deprecated(since = "9")
    @Override
    protected int drawSelectedText(Graphics g, int x,
                                   int y, int p0, int p1) throws BadLocationException {
        return (int) drawSelectedTextImpl(g, x, y, p0, p1, false);
    }

    @Override
    protected float drawSelectedText(Graphics2D g, float x, float y,
                                     int p0, int p1) throws BadLocationException
    {
        return drawSelectedTextImpl(g, x, y, p0, p1, true);
    }

    @SuppressWarnings("deprecation")
    private float drawSelectedTextImpl(Graphics g, float x, float y,
                                       int p0, int p1,
                                       boolean useFPAPI)
            throws BadLocationException {
        g.setColor(selected);
        Container c = getContainer();
        if (c instanceof JPasswordField) {
            JPasswordField f = (JPasswordField) c;
            if (!f.echoCharIsSet()) {
                boolean useDrawUnselectedFPAPI = useFPAPI
                        && drawSelectedTextOverridden
                        && g instanceof Graphics2D;
                return (useFPAPI)
                        ? super.drawSelectedText((Graphics2D) g, x, y, p0, p1)
                        : super.drawSelectedText(g, (int) x, (int) y, p0, p1);
            }
            char echoChar = f.getEchoChar();
            int n = p1 - p0;
            boolean useEchoCharFPAPI = useFPAPI
                    && drawEchoCharacterOverridden
                    && g instanceof Graphics2D;
            for (int i = 0; i < n; i++) {
                x = (useEchoCharFPAPI)
                        ? drawEchoCharacter((Graphics2D) g, x, y, echoChar)
                        : drawEchoCharacter(g, (int) x, (int) y, echoChar);

            }
        }
        return x;
    }

    
Renders the echo character, or whatever graphic should be used
to display the password characters.  The color in the Graphics
object is set to the appropriate foreground color for selected
or unselected text.

Params:
  • g – the graphics context
  • x – the starting X coordinate >= 0
  • y – the starting Y coordinate >= 0
  • c – the echo character
Returns:the updated X position >= 0
Deprecated:replaced by drawEchoCharacter(Graphics2D, float, float, char)
/**
     * Renders the echo character, or whatever graphic should be used
     * to display the password characters.  The color in the Graphics
     * object is set to the appropriate foreground color for selected
     * or unselected text.
     *
     * @param g the graphics context
     * @param x the starting X coordinate &gt;= 0
     * @param y the starting Y coordinate &gt;= 0
     * @param c the echo character
     * @return the updated X position &gt;= 0
     *
     * @deprecated replaced by
     *     {@link #drawEchoCharacter(Graphics2D, float, float, char)}
     */
    @Deprecated(since = "9")
    protected int drawEchoCharacter(Graphics g, int x, int y, char c) {
        return (int) drawEchoCharacterImpl(g, x, y, c, false);
    }

    
Renders the echo character, or whatever graphic should be used
to display the password characters.  The color in the Graphics
object is set to the appropriate foreground color for selected
or unselected text.

Params:
  • g – the graphics context
  • x – the starting X coordinate >= 0
  • y – the starting Y coordinate >= 0
  • c – the echo character
Returns:the updated X position >= 0
Since:9
/**
     * Renders the echo character, or whatever graphic should be used
     * to display the password characters.  The color in the Graphics
     * object is set to the appropriate foreground color for selected
     * or unselected text.
     *
     * @param g the graphics context
     * @param x the starting X coordinate {@code >= 0}
     * @param y the starting Y coordinate {@code >= 0}
     * @param c the echo character
     * @return the updated X position {@code >= 0}
     *
     * @since 9
     */
    protected float drawEchoCharacter(Graphics2D g, float x, float y, char c) {
        return drawEchoCharacterImpl(g, x, y, c, true);
    }

    private float drawEchoCharacterImpl(Graphics g, float x, float y,
                                        char c, boolean useFPAPI) {
        ONE[0] = c;
        SwingUtilities2.drawChars(Utilities.getJComponent(this),
                                  g, ONE, 0, 1, x, y);
        if (useFPAPI) {
            return x + g.getFontMetrics().charWidth(c);
        } else {
            FontRenderContext frc = g.getFontMetrics().getFontRenderContext();
            return x + (float) g.getFont().getStringBounds(ONE, 0, 1, frc).getWidth();
        }
    }

    
Provides a mapping from the document model coordinate space
to the coordinate space of the view mapped to it.

Params:
  • pos – the position to convert >= 0
  • a – the allocated region to render into
Throws:
  • BadLocationException –  if the given position does not
  represent a valid location in the associated document
See Also:
Returns:the bounding box of the given position
/**
     * Provides a mapping from the document model coordinate space
     * to the coordinate space of the view mapped to it.
     *
     * @param pos the position to convert &gt;= 0
     * @param a the allocated region to render into
     * @return the bounding box of the given position
     * @exception BadLocationException  if the given position does not
     *   represent a valid location in the associated document
     * @see View#modelToView
     */
    public Shape modelToView(int pos, Shape a, Position.Bias b) throws BadLocationException {
        Container c = getContainer();
        if (c instanceof JPasswordField) {
            JPasswordField f = (JPasswordField) c;
            if (! f.echoCharIsSet()) {
                return super.modelToView(pos, a, b);
            }
            char echoChar = f.getEchoChar();
            FontMetrics m = f.getFontMetrics(f.getFont());

            Rectangle alloc = adjustAllocation(a).getBounds();
            int dx = (pos - getStartOffset()) * m.charWidth(echoChar);
            alloc.x += dx;
            alloc.width = 1;
            return alloc;
        }
        return null;
    }

    
Provides a mapping from the view coordinate space to the logical
coordinate space of the model.

Params:
  • fx – the X coordinate >= 0.0f
  • fy – the Y coordinate >= 0.0f
  • a – the allocated region to render into
See Also:
Returns:the location within the model that best represents the
 given point in the view
/**
     * Provides a mapping from the view coordinate space to the logical
     * coordinate space of the model.
     *
     * @param fx the X coordinate &gt;= 0.0f
     * @param fy the Y coordinate &gt;= 0.0f
     * @param a the allocated region to render into
     * @return the location within the model that best represents the
     *  given point in the view
     * @see View#viewToModel
     */
    public int viewToModel(float fx, float fy, Shape a, Position.Bias[] bias) {
        bias[0] = Position.Bias.Forward;
        int n = 0;
        Container c = getContainer();
        if (c instanceof JPasswordField) {
            JPasswordField f = (JPasswordField) c;
            if (! f.echoCharIsSet()) {
                return super.viewToModel(fx, fy, a, bias);
            }
            char echoChar = f.getEchoChar();
            int charWidth = f.getFontMetrics(f.getFont()).charWidth(echoChar);
            a = adjustAllocation(a);
            Rectangle alloc = (a instanceof Rectangle) ? (Rectangle)a :
                              a.getBounds();
            n = (charWidth > 0 ?
                 ((int)fx - alloc.x) / charWidth : Integer.MAX_VALUE);
            if (n < 0) {
                n = 0;
            }
            else if (n > (getStartOffset() + getDocument().getLength())) {
                n = getDocument().getLength() - getStartOffset();
            }
        }
        return getStartOffset() + n;
    }

    
Determines the preferred span for this view along an
axis.

Params:
  • axis – may be either View.X_AXIS or View.Y_AXIS
Returns:  the span the view would like to be rendered into >= 0.
          Typically the view is told to render into the span
          that is returned, although there is no guarantee.
          The parent may choose to resize or break the view.
/**
     * Determines the preferred span for this view along an
     * axis.
     *
     * @param axis may be either View.X_AXIS or View.Y_AXIS
     * @return   the span the view would like to be rendered into &gt;= 0.
     *           Typically the view is told to render into the span
     *           that is returned, although there is no guarantee.
     *           The parent may choose to resize or break the view.
     */
    public float getPreferredSpan(int axis) {
        switch (axis) {
        case View.X_AXIS:
            Container c = getContainer();
            if (c instanceof JPasswordField) {
                JPasswordField f = (JPasswordField) c;
                if (f.echoCharIsSet()) {
                    char echoChar = f.getEchoChar();
                    FontMetrics m = f.getFontMetrics(f.getFont());
                    Document doc = getDocument();
                    return m.charWidth(echoChar) * getDocument().getLength();
                }
            }
        }
        return super.getPreferredSpan(axis);
    }

    static char[] ONE = new char[1];

    private final boolean drawEchoCharacterOverridden =
            getFPMethodOverridden(getClass(), "drawEchoCharacter", FPMethodArgs.GNNC);
}