texthighlighter.java

来自「Java生成PDF Java生成PDF Java生成PDF」· Java 代码 · 共 158 行

// $Id: TextHighlighter.java,v 1.3 2007/09/12 10:04:59 mike Exp $

package org.faceless.pdf2.viewer2.feature;

import org.faceless.pdf2.viewer2.*;
import org.faceless.pdf2.*;
import javax.swing.*;
import java.awt.geom.*;
import java.awt.*;
import java.util.*;

/**
 * A feature that allows the highlighting of text in the viewer.
 * The name of this feature is "TextHighlighter".
 * @since 2.8.1
 */
public class TextHighlighter extends ViewerFeature implements DocumentPanelListener, PagePanelListener
{
    private String[] words;
    private PDFPage page;
    private Paint color;
    private Stroke stroke;
    private float margin;
    private int type;

    /**
     * A parameter to {@link #setHighlightType setHighlightType()} that will cause the highlight to be filled.
     * An example would be <code>setHighlightType(TYPE_FILL, new Color(0x70FFFF00, true), null, 0)</code>,
     * to highlight the text with a translucent yellow (the default).
     */
    public static final int TYPE_FILL = 0;

    /**
     * A parameter to {@link #setHighlightType setHighlightType()} that will cause the highlight to be outlined.
     * An example would be <code>setHighlightType(TYPE_OUTLINE, Color.red, new BasicStroke(), 2)</code> to draw
     * a solid red outline around the text with a 2 point margin
     */
    public static final int TYPE_OUTLINE = 1;

    /**
     * A parameter to {@link #setHighlightType setHighlightType()} that will cause the highlight to be outlined.
     * An example would be <code>setHighlightType(TYPE_UNDERLINE, Color.red, new BasicStroke(), 2)</code> to draw
     * a solid red underline two points below the text.
     */
    public static final int TYPE_UNDERLINE = 2;

    /**
     * Create a new TextHighlighter
     */
    public TextHighlighter() {
        super("TextHighlighter");
        words = new String[0];
        setHighlightType(TYPE_FILL, new Color(0x70FFFF00, true), null, 0);
    }

    /**
     * Add a word to highlight to this TextHighlighter.
     * @param word the word to highlight if found
     */
    public void addWord(String word) {
        if (word!=null && word.length()>0 && !Arrays.asList(words).contains(word)) {
            String[] t = new String[words.length+1];
            System.arraycopy(words, 0, t, 0, words.length);
            t[t.length-1] = word;
            words = t;
        }
    }

    public void initialize(PDFViewer viewer) {
        super.initialize(viewer);
        viewer.addDocumentPanelListener(this);
    }

    public void documentUpdated(DocumentPanelEvent event) {
        if (event.getType()=="viewportChanged") {
            event.getDocumentPanel().getViewport().addPagePanelListener(this);
        }
    }

    /**
     * Set the type of Highlight to use
     * @param type one of {@link #TYPE_FILL}, {@link #TYPE_OUTLINE} or {@link #TYPE_UNDERLINE}
     * @param color the color to use - must not be null
     * @param stroke the stroke to use for outline or underlining. May be null.
     * @param margin how many points around the text to use as a margin
     */
    public void setHighlightType(int type, Paint color, Stroke stroke, float margin) {
        if (color==null) throw new IllegalArgumentException("color is null");
        this.type = type;
        this.color = color;
        this.stroke = stroke;
        this.margin = margin;
    }

    /**
     * Draw the highlight. This method may be overridden by subclasses to highlight
     * the text in a different way
     * @param g the Graphics object to paint to
     * @param width the width of the object
     * @param height the height of the object
     */
    public void drawHighlight(Graphics2D g, int width, int height) {
        g.setPaint(color);
        if (type==TYPE_OUTLINE) {
            if (stroke!=null) g.setStroke(stroke);
            g.drawRect(0, 0, width, height);
        } else if (type==TYPE_UNDERLINE) {
            if (stroke!=null) g.setStroke(stroke);
            g.drawLine(0, height, width, height);
        } else {
            g.fillRect(0, 0, width, height);
        }
    }

    public void pageUpdated(PagePanelEvent event) {
        if (event.getType()=="redrawing") {
            event.getPagePanel().setExtractText(true);
        } else if (event.getType()=="redrawn" && words.length>0) {
            PagePanel panel = event.getPagePanel();
            if (panel.getPage()!=page) {
                for (Iterator i = panel.getPageExtractor().getMatchingText(words).iterator();i.hasNext();) {
                    PageExtractor.Text text = (PageExtractor.Text)i.next();
                    JPanel highlight = new JPanel() {
                        public void paintComponent(Graphics g) {
                            drawHighlight((Graphics2D)g, getWidth(), getHeight());
                        }
                    };
                    float[] c = text.getCorners();
                    float[] r = new float[] { c[0]-margin, c[1]-margin, c[4]+margin, c[5]+margin }; // Assume rectangular
                    AnnotationComponentFactory.bindComponentLocation(highlight, r);
                    panel.add(highlight);
                    highlight.setVisible(true);
                }
                page = panel.getPage();
            }
        }
    }

    /*
    public static void main(String[] args) {
        if (args.length<1) {
            System.out.println("Usage: java TextHighlighter file.pdf word\n");
        }
        final java.io.File ffile = new java.io.File(args[0]);
        TextHighlighter hl = new TextHighlighter();
        hl.addWord(args[1]);
        final Collection c = new ArrayList(ViewerFeature.getAllFeatures());
        c.add(hl);
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                PDFViewer viewer = PDFViewer.newPDFViewer(c);
                    if (ffile != null) viewer.loadPDF(ffile);
                }
        });
    }
    */
}