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	/*
	* Copyright (c) 1997, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package javax.swing.text;

	import sun.swing.SwingUtilities2;
	import java.awt.*;
	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 View
	*/
	public class PasswordView extends FieldView {

	/**
	* 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().
	*
	* @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
	*/
	protected int drawUnselectedText(Graphics g, int x, int y,
	int p0, int p1) throws BadLocationException {

	Container c = getContainer();
	if (c instanceof JPasswordField) {
	JPasswordField f = (JPasswordField) c;
	if (! f.echoCharIsSet()) {
	return super.drawUnselectedText(g, x, y, p0, p1);
	}
	if (f.isEnabled()) {
	g.setColor(f.getForeground());
	}
	else {
	g.setColor(f.getDisabledTextColor());
	}
	char echoChar = f.getEchoChar();
	int n = p1 - p0;
	for (int i = 0; i < n; i++) {
	x = drawEchoCharacter(g, x, 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.
	*
	* @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
	*/
	protected int drawSelectedText(Graphics g, int x,
	int y, int p0, int p1) throws BadLocationException {
	g.setColor(selected);
	Container c = getContainer();
	if (c instanceof JPasswordField) {
	JPasswordField f = (JPasswordField) c;
	if (! f.echoCharIsSet()) {
	return super.drawSelectedText(g, x, y, p0, p1);
	}
	char echoChar = f.getEchoChar();
	int n = p1 - p0;
	for (int i = 0; i < n; i++) {
	x = drawEchoCharacter(g, x, 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.
	*
	* @param g the graphics context
	* @param x the starting X coordinate >= 0
	* @param y the starting Y coordinate >= 0
	* @param c the echo character
	* @return the updated X position >= 0
	*/
	protected int drawEchoCharacter(Graphics g, int x, int y, char c) {
	ONE[0] = c;
	SwingUtilities2.drawChars(Utilities.getJComponent(this),
	g, ONE, 0, 1, x, y);
	return x + g.getFontMetrics().charWidth(c);
	}

	/**
	* 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 >= 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.
	*
	* @param fx the X coordinate >= 0.0f
	* @param fy the Y coordinate >= 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.
	*
	* @param axis may be either View.X_AXIS or View.Y_AXIS
	* @return 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.
	*/
	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];
	}

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