rprintutilities.java

具有不同语法高亮的编辑器实例

/*
 * 11/14/2003
 *
 * RPrintUtilities.java - A collection of static methods useful for printing
 *                        text from Swing text components.
 * Copyright (C) 2003 Robert Futrell
 * [e-mail]
 * www.website.com
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or any later version.
 *
 * This program 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 for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 */
package org.fife.print;

import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
import javax.swing.text.Element;
import javax.swing.text.Segment;
import javax.swing.text.JTextComponent;
import javax.swing.text.TabExpander;
import javax.swing.text.Utilities;
import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.print.*;



/**
 * A collection of static methods useful for printing text from Swing text components.
 *
 * @author Robert Futrell
 * @version 1.0
 */
public abstract class RPrintUtilities {

	private static int currentDocLineNumber;		// The line number in the document we are currently on.
	private static int numDocLines;				// The number of lines in the current document.
	private static Element rootElement;			// The first Element (line) in the current document.

	// The characters at which to break a line if implementing word wrap.
	private static final char [] breakChars = { ' ', '\t', ',', '.', ';', '?', '!' };

	// These variables are 'global' because RPrintTabExpander uses them.
	private static int xOffset;					// The x-offset (for the page margin) when printing.
	private static int tabSizeInSpaces;			// The length of a tab, in spaces.
	private static FontMetrics fontMetrics;			// The metrics of the font currently being used to print.


/*****************************************************************************/


	/**
	 * Returns the position closest to, but before, position <code>maxCharsPerLine</code> in
	 * <code>line</code> of one of the chars in <code>breakChars</code>, or simply returns
	 * <code>maxCharsPerLine-1</code> if none of the <code>breakChars</code> comes before
	 * that position.  This position represents the logical line break for this <code>java.lang.String</code>
	 * if it is being printed in a monospaced font when lines can only be <code>maxCharsPerLine</code>
	 * characters long.
	 *
	 * @param line The text being printed.
	 * @param maxCharsPerLine Only up-to this many characters from <code>line</code> can be printed
	 *                        on one line.
	 * @return The logical position at which to stop printing <code>line</code> to simulate
	 *         word wrap.
	 */
	private static int getLineBreakPoint(String line, final int maxCharsPerLine) {

		int breakPoint = -1;
		for (int i=0; i<breakChars.length; i++) {
			int breakCharPos = line.lastIndexOf(breakChars[i], maxCharsPerLine-1);
			if (breakCharPos > breakPoint)
				breakPoint = breakCharPos;
		}

		return (breakPoint==-1 ? maxCharsPerLine-1 : breakPoint);

	}


/*****************************************************************************/


	/**
	 * Prints a <code>Document</code> using a monospaced font, and does no word wrapping (ie,
	 * words will wrap mid-word to the next line).  This method is expected to be called from
	 * Printable 'print(Graphics g)' functions.
	 *
	 * @param g The graphics context to write to.
	 * @param doc The <code>javax.swing.text.Document</code> to print.
	 * @param fontSize the point size to use for the monospaced font.
	 * @param pageIndex The page number to print.
	 * @param pageFormat The format to print the page with.
	 * @param tabSize The number of spaces to expand tabs to.
	 *
	 * @see #printDocumentMonospacedWordWrap
	 */
	public static int printDocumentMonospaced(Graphics g, Document doc, int fontSize, int pageIndex,
							PageFormat pageFormat, int tabSize) {

		g.setColor(Color.BLACK);
		g.setFont(new Font("monospaced", Font.PLAIN, fontSize));

		// Initialize our static variables (these are used by our tab expander below).
		tabSizeInSpaces = tabSize;
		fontMetrics = g.getFontMetrics();

		// Create our tab expander.
		//RPrintTabExpander tabExpander = new RPrintTabExpander();

		// Get width and height of characters in this monospaced font.
		int fontWidth = fontMetrics.charWidth('w');			// Any character will do here, since font is monospaced.
		int fontHeight = fontMetrics.getHeight();

		int MAX_CHARS_PER_LINE = (int)pageFormat.getImageableWidth() / fontWidth;
		int MAX_LINES_PER_PAGE = (int)pageFormat.getImageableHeight() / fontHeight;

		final int STARTING_LINE_NUMBER = MAX_LINES_PER_PAGE * pageIndex;

		// The (x,y) coordinate to print at (in pixels, not characters).
		// Since y is the baseline of where we'll start printing (not the top-left
		// corner), we offset it by the font's ascent ( + 1 just for good measure).
		xOffset = (int)pageFormat.getImageableX();
		int y = (int)pageFormat.getImageableY() + fontMetrics.getAscent() + 1;

		// A counter to keep track of the number of lines that WOULD HAVE been printed if we were printing all lines.
		int numPrintedLines = 0;

		// Keep going while there are more lines in the document.
		currentDocLineNumber = 0;						// The line number of the document we're currently on.
		rootElement = doc.getDefaultRootElement();		// To shorten accesses in our loop.
		numDocLines = rootElement.getElementCount();	// The number of lines in our document.
		while (currentDocLineNumber<numDocLines) {

			// Get the line we are going to print.
			String curLineString;
			Element currentLine = rootElement.getElement(currentDocLineNumber);
			try {
				curLineString = doc.getText(currentLine.getStartOffset(), currentLine.getEndOffset()-currentLine.getStartOffset());
			} catch (BadLocationException ble) {
				System.err.println("EXCEPTION - " + ble);
				return Printable.NO_SUCH_PAGE;
			}

			// Get rid of newlines, because they end up as boxes if you don't; this is a monospaced font.
			curLineString = curLineString.replaceAll("\n", "");

			// Replace tabs with how many spaces they should be.
			if (tabSizeInSpaces == 0) {
				curLineString.replaceAll("\t", "");
			}
			else {
				int tabIndex = curLineString.indexOf('\t');
				while (tabIndex > -1) {
					int spacesNeeded = tabSizeInSpaces - (tabIndex % tabSizeInSpaces);
					String replacementString = "";
					for (int i=0; i<spacesNeeded; i++)
						replacementString += " ";
					curLineString = curLineString.replaceFirst("\t", replacementString);	// Note that "\t" is actually a regex for this method.
					tabIndex = curLineString.indexOf('\t');
				}
			}

			// If this document line is too long to fit on one printed line on the page,
			// break it up into multpile lines.
			while (curLineString.length() > MAX_CHARS_PER_LINE) {

				numPrintedLines++;
				if (numPrintedLines > STARTING_LINE_NUMBER) {
						g.drawString(curLineString.substring(0,MAX_CHARS_PER_LINE), xOffset,y);
						y += fontHeight;
						if (numPrintedLines==STARTING_LINE_NUMBER+MAX_LINES_PER_PAGE)
							return Printable.PAGE_EXISTS;
	 			}

				curLineString = curLineString.substring(MAX_CHARS_PER_LINE, curLineString.length());

			}

			currentDocLineNumber += 1; // We have printed one more line from the document.

			numPrintedLines++;
			if (numPrintedLines>STARTING_LINE_NUMBER) {
				g.drawString(curLineString, xOffset,y);
				y += fontHeight;
				if (numPrintedLines==STARTING_LINE_NUMBER+MAX_LINES_PER_PAGE)
					return Printable.PAGE_EXISTS;
			}


		}

		// Now, the whole document has been "printed."  Decide if this page had any text on it or not.
		if (numPrintedLines > STARTING_LINE_NUMBER)
			return Printable.PAGE_EXISTS;
		return Printable.NO_SUCH_PAGE;

	}


/*****************************************************************************/


	/**
	 * Prints a <code>Document</code> using a monospaced font, word wrapping on the characters
	 * ' ', '\t', '\n', ',', '.', and ';'.  This method is expected to be called from
	 * Printable 'print(Graphics g)' functions.
	 *
	 * @param g The graphics context to write to.
	 * @param doc The <code>javax.swing.text.Document</code> to print.
	 * @param fontSize the point size to use for the monospaced font.
	 * @param pageIndex The page number to print.
	 * @param pageFormat The format to print the page with.
	 * @param tabSize The number of spaces to expand tabs to.
	 *
	 * @see #printDocumentMonospaced
	 */
	public static int printDocumentMonospacedWordWrap(Graphics g, Document doc,
											int fontSize, int pageIndex,
											PageFormat pageFormat, int tabSize) {

		g.setColor(Color.BLACK);
		g.setFont(new Font("monospaced", Font.PLAIN, fontSize));

		// Initialize our static variables (these are used by our tab expander below).
		tabSizeInSpaces = tabSize;
		fontMetrics = g.getFontMetrics();

		// Create our tab expander.
		//RPrintTabExpander tabExpander = new RPrintTabExpander();

		// Get width and height of characters in this monospaced font.
		int fontWidth = fontMetrics.charWidth('w'); 	// Any character will do here, since font is monospaced.
		int fontHeight = fontMetrics.getHeight();

		int MAX_CHARS_PER_LINE = (int)pageFormat.getImageableWidth() / fontWidth;
		int MAX_LINES_PER_PAGE = (int)pageFormat.getImageableHeight() / fontHeight;

		final int STARTING_LINE_NUMBER = MAX_LINES_PER_PAGE * pageIndex;

		// The (x,y) coordinate to print at (in pixels, not characters).
		// Since y is the baseline of where we'll start printing (not the top-left
		// corner), we offset it by the font's ascent ( + 1 just for good measure).
		xOffset = (int)pageFormat.getImageableX();
		int y = (int)pageFormat.getImageableY() + fontMetrics.getAscent() + 1;

		// A counter to keep track of the number of lines that WOULD HAVE been printed if we were printing all lines.
		int numPrintedLines = 0;

		// Keep going while there are more lines in the document.
		currentDocLineNumber = 0;						// The line number of the document we're currently on.
		rootElement = doc.getDefaultRootElement();		// To shorten accesses in our loop.
		numDocLines = rootElement.getElementCount();	// The number of lines in our document.
		while (currentDocLineNumber<numDocLines) {

			// Get the line we are going to print.
			String curLineString;
			Element currentLine = rootElement.getElement(currentDocLineNumber);
			try {
				curLineString = doc.getText(currentLine.getStartOffset(), currentLine.getEndOffset()-currentLine.getStartOffset());
			} catch (BadLocationException ble) {
				System.err.println("EXCEPTION - " + ble);
				return Printable.NO_SUCH_PAGE;
			}

			// Remove newlines, because they end up as boxes if you don't; this is a monospaced font.
			curLineString = curLineString.replaceAll("\n", "");