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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * This code is free software; you can redistribute it and/or modify it
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 *
 * This code is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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 * version 2 for more details (a copy is included in the LICENSE file that
 * accompanied this code).
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 * 2 along with this work; if not, write to the Free Software Foundation,
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 *
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package javax.swing.text;

import java.util.Vector;
import java.awt.*;
import javax.swing.plaf.*;
import javax.swing.*;


Implements the Highlighter interfaces.  Implements a simple highlight
painter that renders in a solid color.

Author: Timothy Prinzing
See Also:
/**
 * Implements the Highlighter interfaces.  Implements a simple highlight
 * painter that renders in a solid color.
 *
 * @author  Timothy Prinzing
 * @see     Highlighter
 */
public class DefaultHighlighter extends LayeredHighlighter {

    
Creates a new DefaultHighlighther object.

/**
     * Creates a new DefaultHighlighther object.
     */
    public DefaultHighlighter() {
        drawsLayeredHighlights = true;
    }

    // ---- Highlighter methods ----------------------------------------------

    
Renders the highlights.

Params:
  • g – the graphics context
/**
     * Renders the highlights.
     *
     * @param g the graphics context
     */
    public void paint(Graphics g) {
        // PENDING(prinz) - should cull ranges not visible
        int len = highlights.size();
        for (int i = 0; i < len; i++) {
            HighlightInfo info = (HighlightInfo) highlights.elementAt(i);
            if (!(info instanceof LayeredHighlightInfo)) {
                // Avoid allocing unless we need it.
                Rectangle a = component.getBounds();
                Insets insets = component.getInsets();
                a.x = insets.left;
                a.y = insets.top;
                a.width -= insets.left + insets.right;
                a.height -= insets.top + insets.bottom;
                for (; i < len; i++) {
                    info = (HighlightInfo)highlights.elementAt(i);
                    if (!(info instanceof LayeredHighlightInfo)) {
                        Highlighter.HighlightPainter p = info.getPainter();
                        p.paint(g, info.getStartOffset(), info.getEndOffset(),
                                a, component);
                    }
                }
            }
        }
    }

    
Called when the UI is being installed into the
interface of a JTextComponent.  Installs the editor, and
removes any existing highlights.

Params:
  • c – the editor component
See Also:
/**
     * Called when the UI is being installed into the
     * interface of a JTextComponent.  Installs the editor, and
     * removes any existing highlights.
     *
     * @param c the editor component
     * @see Highlighter#install
     */
    public void install(JTextComponent c) {
        component = c;
        removeAllHighlights();
    }

    
Called when the UI is being removed from the interface of
a JTextComponent.

Params:
  • c – the component
See Also:
/**
     * Called when the UI is being removed from the interface of
     * a JTextComponent.
     *
     * @param c the component
     * @see Highlighter#deinstall
     */
    public void deinstall(JTextComponent c) {
        component = null;
    }

    
Adds a highlight to the view.  Returns a tag that can be used
to refer to the highlight.

Params:
  • p0 –   the start offset of the range to highlight >= 0
  • p1 –   the end offset of the range to highlight >= p0
  • p –    the painter to use to actually render the highlight
Throws:
Returns:    an object that can be used as a tag
  to refer to the highlight
/**
     * Adds a highlight to the view.  Returns a tag that can be used
     * to refer to the highlight.
     *
     * @param p0   the start offset of the range to highlight >= 0
     * @param p1   the end offset of the range to highlight >= p0
     * @param p    the painter to use to actually render the highlight
     * @return     an object that can be used as a tag
     *   to refer to the highlight
     * @exception BadLocationException if the specified location is invalid
     */
    public Object addHighlight(int p0, int p1, Highlighter.HighlightPainter p) throws BadLocationException {
        Document doc = component.getDocument();
        HighlightInfo i = (getDrawsLayeredHighlights() &&
                           (p instanceof LayeredHighlighter.LayerPainter)) ?
                          new LayeredHighlightInfo() : new HighlightInfo();
        i.painter = p;
        i.p0 = doc.createPosition(p0);
        i.p1 = doc.createPosition(p1);
        highlights.addElement(i);
        safeDamageRange(p0, p1);
        return i;
    }

    
Removes a highlight from the view.

Params:
  • tag – the reference to the highlight
/**
     * Removes a highlight from the view.
     *
     * @param tag the reference to the highlight
     */
    public void removeHighlight(Object tag) {
        if (tag instanceof LayeredHighlightInfo) {
            LayeredHighlightInfo lhi = (LayeredHighlightInfo)tag;
            if (lhi.width > 0 && lhi.height > 0) {
                component.repaint(lhi.x, lhi.y, lhi.width, lhi.height);
            }
        }
        else {
            HighlightInfo info = (HighlightInfo) tag;
            safeDamageRange(info.p0, info.p1);
        }
        highlights.removeElement(tag);
    }

    
Removes all highlights.

/**
     * Removes all highlights.
     */
    public void removeAllHighlights() {
        TextUI mapper = component.getUI();
        if (getDrawsLayeredHighlights()) {
            int len = highlights.size();
            if (len != 0) {
                int minX = 0;
                int minY = 0;
                int maxX = 0;
                int maxY = 0;
                int p0 = -1;
                int p1 = -1;
                for (int i = 0; i < len; i++) {
                    HighlightInfo hi = (HighlightInfo)highlights.elementAt(i);
                    if (hi instanceof LayeredHighlightInfo) {
                        LayeredHighlightInfo info = (LayeredHighlightInfo)hi;
                        minX = Math.min(minX, info.x);
                        minY = Math.min(minY, info.y);
                        maxX = Math.max(maxX, info.x + info.width);
                        maxY = Math.max(maxY, info.y + info.height);
                    }
                    else {
                        if (p0 == -1) {
                            p0 = hi.p0.getOffset();
                            p1 = hi.p1.getOffset();
                        }
                        else {
                            p0 = Math.min(p0, hi.p0.getOffset());
                            p1 = Math.max(p1, hi.p1.getOffset());
                        }
                    }
                }
                if (minX != maxX && minY != maxY) {
                    component.repaint(minX, minY, maxX - minX, maxY - minY);
                }
                if (p0 != -1) {
                    try {
                        safeDamageRange(p0, p1);
                    } catch (BadLocationException e) {}
                }
                highlights.removeAllElements();
            }
        }
        else if (mapper != null) {
            int len = highlights.size();
            if (len != 0) {
                int p0 = Integer.MAX_VALUE;
                int p1 = 0;
                for (int i = 0; i < len; i++) {
                    HighlightInfo info = (HighlightInfo) highlights.elementAt(i);
                    p0 = Math.min(p0, info.p0.getOffset());
                    p1 = Math.max(p1, info.p1.getOffset());
                }
                try {
                    safeDamageRange(p0, p1);
                } catch (BadLocationException e) {}

                highlights.removeAllElements();
            }
        }
    }

    
Changes a highlight.

Params:
  • tag – the highlight tag
  • p0 – the beginning of the range >= 0
  • p1 – the end of the range >= p0
Throws:
/**
     * Changes a highlight.
     *
     * @param tag the highlight tag
     * @param p0 the beginning of the range >= 0
     * @param p1 the end of the range >= p0
     * @exception BadLocationException if the specified location is invalid
     */
    public void changeHighlight(Object tag, int p0, int p1) throws BadLocationException {
        Document doc = component.getDocument();
        if (tag instanceof LayeredHighlightInfo) {
            LayeredHighlightInfo lhi = (LayeredHighlightInfo)tag;
            if (lhi.width > 0 && lhi.height > 0) {
                component.repaint(lhi.x, lhi.y, lhi.width, lhi.height);
            }
            // Mark the highlights region as invalid, it will reset itself
            // next time asked to paint.
            lhi.width = lhi.height = 0;
            lhi.p0 = doc.createPosition(p0);
            lhi.p1 = doc.createPosition(p1);
            safeDamageRange(Math.min(p0, p1), Math.max(p0, p1));
        }
        else {
            HighlightInfo info = (HighlightInfo) tag;
            int oldP0 = info.p0.getOffset();
            int oldP1 = info.p1.getOffset();
            if (p0 == oldP0) {
                safeDamageRange(Math.min(oldP1, p1),
                                   Math.max(oldP1, p1));
            } else if (p1 == oldP1) {
                safeDamageRange(Math.min(p0, oldP0),
                                   Math.max(p0, oldP0));
            } else {
                safeDamageRange(oldP0, oldP1);
                safeDamageRange(p0, p1);
            }
            info.p0 = doc.createPosition(p0);
            info.p1 = doc.createPosition(p1);
        }
    }

    
Makes a copy of the highlights.  Does not actually clone each highlight,
but only makes references to them.

See Also:
Returns:the copy
/**
     * Makes a copy of the highlights.  Does not actually clone each highlight,
     * but only makes references to them.
     *
     * @return the copy
     * @see Highlighter#getHighlights
     */
    public Highlighter.Highlight[] getHighlights() {
        int size = highlights.size();
        if (size == 0) {
            return noHighlights;
        }
        Highlighter.Highlight[] h = new Highlighter.Highlight[size];
        highlights.copyInto(h);
        return h;
    }

    
When leaf Views (such as LabelView) are rendering they should
call into this method. If a highlight is in the given region it will
be drawn immediately.

Params:
  • g – Graphics used to draw
  • p0 – starting offset of view
  • p1 – ending offset of view
  • viewBounds – Bounds of View
  • editor – JTextComponent
  • view – View instance being rendered
/**
     * When leaf Views (such as LabelView) are rendering they should
     * call into this method. If a highlight is in the given region it will
     * be drawn immediately.
     *
     * @param g Graphics used to draw
     * @param p0 starting offset of view
     * @param p1 ending offset of view
     * @param viewBounds Bounds of View
     * @param editor JTextComponent
     * @param view View instance being rendered
     */
    public void paintLayeredHighlights(Graphics g, int p0, int p1,
                                       Shape viewBounds,
                                       JTextComponent editor, View view) {
        for (int counter = highlights.size() - 1; counter >= 0; counter--) {
            Object tag = highlights.elementAt(counter);
            if (tag instanceof LayeredHighlightInfo) {
                LayeredHighlightInfo lhi = (LayeredHighlightInfo)tag;
                int start = lhi.getStartOffset();
                int end = lhi.getEndOffset();
                if ((p0 < start && p1 > start) ||
                    (p0 >= start && p0 < end)) {
                    lhi.paintLayeredHighlights(g, p0, p1, viewBounds,
                                               editor, view);
                }
            }
        }
    }

    
Queues damageRange() call into event dispatch thread
to be sure that views are in consistent state.

/**
     * Queues damageRange() call into event dispatch thread
     * to be sure that views are in consistent state.
     */
    private void safeDamageRange(final Position p0, final Position p1) {
        safeDamager.damageRange(p0, p1);
    }

    
Queues damageRange() call into event dispatch thread
to be sure that views are in consistent state.

/**
     * Queues damageRange() call into event dispatch thread
     * to be sure that views are in consistent state.
     */
    private void safeDamageRange(int a0, int a1) throws BadLocationException {
        Document doc = component.getDocument();
        safeDamageRange(doc.createPosition(a0), doc.createPosition(a1));
    }

    
If true, highlights are drawn as the Views draw the text. That is
the Views will call into paintLayeredHighlight which
will result in a rectangle being drawn before the text is drawn
(if the offsets are in a highlighted region that is). For this to
work the painter supplied must be an instance of
LayeredHighlightPainter.

/**
     * If true, highlights are drawn as the Views draw the text. That is
     * the Views will call into <code>paintLayeredHighlight</code> which
     * will result in a rectangle being drawn before the text is drawn
     * (if the offsets are in a highlighted region that is). For this to
     * work the painter supplied must be an instance of
     * LayeredHighlightPainter.
     */
    public void setDrawsLayeredHighlights(boolean newValue) {
        drawsLayeredHighlights = newValue;
    }

    public boolean getDrawsLayeredHighlights() {
        return drawsLayeredHighlights;
    }

    // ---- member variables --------------------------------------------

    private final static Highlighter.Highlight[] noHighlights =
            new Highlighter.Highlight[0];
    private Vector highlights = new Vector();  // Vector<HighlightInfo>
    private JTextComponent component;
    private boolean drawsLayeredHighlights;
    private SafeDamager safeDamager = new SafeDamager();


    
Default implementation of LayeredHighlighter.LayerPainter that can
be used for painting highlights.


As of 1.4 this field is final.

/**
     * Default implementation of LayeredHighlighter.LayerPainter that can
     * be used for painting highlights.
     * <p>
     * As of 1.4 this field is final.
     */
    public static final LayeredHighlighter.LayerPainter DefaultPainter = new DefaultHighlightPainter(null);


    
Simple highlight painter that fills a highlighted area with
a solid color.

/**
     * Simple highlight painter that fills a highlighted area with
     * a solid color.
     */
    public static class DefaultHighlightPainter extends LayeredHighlighter.LayerPainter {

        
Constructs a new highlight painter. If c is null,
the JTextComponent will be queried for its selection color.

Params:
  • c – the color for the highlight
/**
         * Constructs a new highlight painter. If <code>c</code> is null,
         * the JTextComponent will be queried for its selection color.
         *
         * @param c the color for the highlight
         */
        public DefaultHighlightPainter(Color c) {
            color = c;
        }

        
Returns the color of the highlight.

Returns:the color
/**
         * Returns the color of the highlight.
         *
         * @return the color
         */
        public Color getColor() {
            return color;
        }

        // --- HighlightPainter methods ---------------------------------------

        
Paints a highlight.

Params:
  • g – the graphics context
  • offs0 – the starting model offset >= 0
  • offs1 – the ending model offset >= offs1
  • bounds – the bounding box for the highlight
  • c – the editor
/**
         * Paints a highlight.
         *
         * @param g the graphics context
         * @param offs0 the starting model offset >= 0
         * @param offs1 the ending model offset >= offs1
         * @param bounds the bounding box for the highlight
         * @param c the editor
         */
        public void paint(Graphics g, int offs0, int offs1, Shape bounds, JTextComponent c) {
            Rectangle alloc = bounds.getBounds();
            try {
                // --- determine locations ---
                TextUI mapper = c.getUI();
                Rectangle p0 = mapper.modelToView(c, offs0);
                Rectangle p1 = mapper.modelToView(c, offs1);

                // --- render ---
                Color color = getColor();

                if (color == null) {
                    g.setColor(c.getSelectionColor());
                }
                else {
                    g.setColor(color);
                }
                if (p0.y == p1.y) {
                    // same line, render a rectangle
                    Rectangle r = p0.union(p1);
                    g.fillRect(r.x, r.y, r.width, r.height);
                } else {
                    // different lines
                    int p0ToMarginWidth = alloc.x + alloc.width - p0.x;
                    g.fillRect(p0.x, p0.y, p0ToMarginWidth, p0.height);
                    if ((p0.y + p0.height) != p1.y) {
                        g.fillRect(alloc.x, p0.y + p0.height, alloc.width,
                                   p1.y - (p0.y + p0.height));
                    }
                    g.fillRect(alloc.x, p1.y, (p1.x - alloc.x), p1.height);
                }
            } catch (BadLocationException e) {
                // can't render
            }
        }

        // --- LayerPainter methods ----------------------------
        
Paints a portion of a highlight.

Params:
  • g – the graphics context
  • offs0 – the starting model offset >= 0
  • offs1 – the ending model offset >= offs1
  • bounds – the bounding box of the view, which is not
       necessarily the region to paint.
  • c – the editor
  • view – View painting for
Returns:region drawing occured in
/**
         * Paints a portion of a highlight.
         *
         * @param g the graphics context
         * @param offs0 the starting model offset >= 0
         * @param offs1 the ending model offset >= offs1
         * @param bounds the bounding box of the view, which is not
         *        necessarily the region to paint.
         * @param c the editor
         * @param view View painting for
         * @return region drawing occured in
         */
        public Shape paintLayer(Graphics g, int offs0, int offs1,
                                Shape bounds, JTextComponent c, View view) {
            Color color = getColor();

            if (color == null) {
                g.setColor(c.getSelectionColor());
            }
            else {
                g.setColor(color);
            }

            Rectangle r;

            if (offs0 == view.getStartOffset() &&
                offs1 == view.getEndOffset()) {
                // Contained in view, can just use bounds.
                if (bounds instanceof Rectangle) {
                    r = (Rectangle) bounds;
                }
                else {
                    r = bounds.getBounds();
                }
            }
            else {
                // Should only render part of View.
                try {
                    // --- determine locations ---
                    Shape shape = view.modelToView(offs0, Position.Bias.Forward,
                                                   offs1,Position.Bias.Backward,
                                                   bounds);
                    r = (shape instanceof Rectangle) ?
                                  (Rectangle)shape : shape.getBounds();
                } catch (BadLocationException e) {
                    // can't render
                    r = null;
                }
            }

            if (r != null) {
                // If we are asked to highlight, we should draw something even
                // if the model-to-view projection is of zero width (6340106).
                r.width = Math.max(r.width, 1);

                g.fillRect(r.x, r.y, r.width, r.height);
            }

            return r;
        }

        private Color color;

    }


    class HighlightInfo implements Highlighter.Highlight {

        public int getStartOffset() {
            return p0.getOffset();
        }

        public int getEndOffset() {
            return p1.getOffset();
        }

        public Highlighter.HighlightPainter getPainter() {
            return painter;
        }

        Position p0;
        Position p1;
        Highlighter.HighlightPainter painter;
    }


    
LayeredHighlightPainter is used when a drawsLayeredHighlights is
true. It maintains a rectangle of the region to paint.

/**
     * LayeredHighlightPainter is used when a drawsLayeredHighlights is
     * true. It maintains a rectangle of the region to paint.
     */
    class LayeredHighlightInfo extends HighlightInfo {

        void union(Shape bounds) {
            if (bounds == null)
                return;

            Rectangle alloc;
            if (bounds instanceof Rectangle) {
                alloc = (Rectangle)bounds;
            }
            else {
                alloc = bounds.getBounds();
            }
            if (width == 0 || height == 0) {
                x = alloc.x;
                y = alloc.y;
                width = alloc.width;
                height = alloc.height;
            }
            else {
                width = Math.max(x + width, alloc.x + alloc.width);
                height = Math.max(y + height, alloc.y + alloc.height);
                x = Math.min(x, alloc.x);
                width -= x;
                y = Math.min(y, alloc.y);
                height -= y;
            }
        }

        
Restricts the region based on the receivers offsets and messages
the painter to paint the region.

/**
         * Restricts the region based on the receivers offsets and messages
         * the painter to paint the region.
         */
        void paintLayeredHighlights(Graphics g, int p0, int p1,
                                    Shape viewBounds, JTextComponent editor,
                                    View view) {
            int start = getStartOffset();
            int end = getEndOffset();
            // Restrict the region to what we represent
            p0 = Math.max(start, p0);
            p1 = Math.min(end, p1);
            // Paint the appropriate region using the painter and union
            // the effected region with our bounds.
            union(((LayeredHighlighter.LayerPainter)painter).paintLayer
                  (g, p0, p1, viewBounds, editor, view));
        }

        int x;
        int y;
        int width;
        int height;
    }

    
This class invokes mapper.damageRange in
EventDispatchThread. The only one instance per Highlighter
is cretaed. When a number of ranges should be damaged
it collects them into queue and damages
them in consecutive order in run
call.

/**
     * This class invokes <code>mapper.damageRange</code> in
     * EventDispatchThread. The only one instance per Highlighter
     * is cretaed. When a number of ranges should be damaged
     * it collects them into queue and damages
     * them in consecutive order in <code>run</code>
     * call.
     */
    class SafeDamager implements Runnable {
        private Vector p0 = new Vector(10);
        private Vector p1 = new Vector(10);
        private Document lastDoc = null;

        
Executes range(s) damage and cleans range queue.

/**
         * Executes range(s) damage and cleans range queue.
         */
        public synchronized void run() {
            if (component != null) {
                TextUI mapper = component.getUI();
                if (mapper != null && lastDoc == component.getDocument()) {
                    // the Document should be the same to properly
                    // display highlights
                    int len = p0.size();
                    for (int i = 0; i < len; i++){
                        mapper.damageRange(component,
                                ((Position)p0.get(i)).getOffset(),
                                ((Position)p1.get(i)).getOffset());
                    }
                }
            }
            p0.clear();
            p1.clear();

            // release reference
            lastDoc = null;
        }

        
Adds the range to be damaged into the range queue. If the
range queue is empty (the first call or run() was already
invoked) then adds this class instance into EventDispatch
queue.
The method also tracks if the current document changed or
component is null. In this case it removes all ranges added
before from range queue.

/**
         * Adds the range to be damaged into the range queue. If the
         * range queue is empty (the first call or run() was already
         * invoked) then adds this class instance into EventDispatch
         * queue.
         *
         * The method also tracks if the current document changed or
         * component is null. In this case it removes all ranges added
         * before from range queue.
         */
        public synchronized void damageRange(Position pos0, Position pos1) {
            if (component == null) {
                p0.clear();
                lastDoc = null;
                return;
            }

            boolean addToQueue = p0.isEmpty();
            Document curDoc = component.getDocument();
            if (curDoc != lastDoc) {
                if (!p0.isEmpty()) {
                    p0.clear();
                    p1.clear();
                }
                lastDoc = curDoc;
            }
            p0.add(pos0);
            p1.add(pos1);

            if (addToQueue) {
                SwingUtilities.invokeLater(this);
            }
        }
    }
}