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/**
* Class: Example5
* <p>
*
* Example of using the TextLayout class to format a text paragraph. with full
* justification.
* <p>
*
* @author Jean-Pierre Dube <jpdube@videotron.ca>
* @version 1.0
* @since 1.0
*/
import java.awt.BasicStroke;
import java.awt.Color;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.font.FontRenderContext;
import java.awt.font.LineBreakMeasurer;
import java.awt.font.TextAttribute;
import java.awt.font.TextLayout;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import java.awt.print.Book;
import java.awt.print.PageFormat;
import java.awt.print.Printable;
import java.awt.print.PrinterJob;
import java.text.AttributedString;
import java.util.Vector;
public class JavaWorldPrintExample5 {
public static void main(String[] args) {
JavaWorldPrintExample5 example = new JavaWorldPrintExample5();
System.exit(0);
}
//--- Private instances declarations
private final static int POINTS_PER_INCH = 72;
/**
* Constructor: Example5
* <p>
*
*/
public JavaWorldPrintExample5() {
//--- Create a new PrinterJob object
PrinterJob printJob = PrinterJob.getPrinterJob();
//--- Create a new book to add pages to
Book book = new Book();
//--- Add the cover page using the default page format for this print
// job
book.append(new IntroPage(), printJob.defaultPage());
//--- Add the document page using a landscape page format
PageFormat documentPageFormat = new PageFormat();
documentPageFormat.setOrientation(PageFormat.LANDSCAPE);
book.append(new Document(), documentPageFormat);
//--- Tell the printJob to use the book as the pageable object
printJob.setPageable(book);
//--- Show the print dialog box. If the user click the
//--- print button we then proceed to print else we cancel
//--- the process.
if (printJob.printDialog()) {
try {
printJob.print();
} catch (Exception PrintException) {
PrintException.printStackTrace();
}
}
}
/**
* Class: IntroPage
* <p>
*
* This class defines the painter for the cover page by implementing the
* Printable interface.
* <p>
*
* @author Jean-Pierre Dube <jpdube@videotron.ca>
* @version 1.0
* @since 1.0
* @see Printable
*/
private class IntroPage implements Printable {
/**
* Method: print
* <p>
*
* @param g
* a value of type Graphics
* @param pageFormat
* a value of type PageFormat
* @param page
* a value of type int
* @return a value of type int
*/
public int print(Graphics g, PageFormat pageFormat, int page) {
//--- Create the Graphics2D object
Graphics2D g2d = (Graphics2D) g;
//--- Translate the origin to 0,0 for the top left corner
g2d.translate(pageFormat.getImageableX(), pageFormat
.getImageableY());
//--- Set the default drawing color to black
g2d.setPaint(Color.black);
//--- Draw a border arround the page
Rectangle2D.Double border = new Rectangle2D.Double(0, 0, pageFormat
.getImageableWidth(), pageFormat.getImageableHeight());
g2d.draw(border);
//--- Print the title
String titleText = "Printing in Java Part 2, Example 5, Using full justification";
Font titleFont = new Font("helvetica", Font.BOLD, 18);
g2d.setFont(titleFont);
//--- Compute the horizontal center of the page
FontMetrics fontMetrics = g2d.getFontMetrics();
double titleX = (pageFormat.getImageableWidth() / 2)
- (fontMetrics.stringWidth(titleText) / 2);
double titleY = 3 * POINTS_PER_INCH;
g2d.drawString(titleText, (int) titleX, (int) titleY);
return (PAGE_EXISTS);
}
}
/**
* Class: Document
* <p>
*
* This class is the painter for the document content. The print method will
* render a text paragraph fully justified.
* <p>
*
*
* @author Jean-Pierre Dube <jpdube@videotron.ca>
* @version 1.0
* @since 1.0
* @see Printable
*/
private class Document implements Printable {
/**
* Method: print
* <p>
*
* @param g
* a value of type Graphics
* @param pageFormat
* a value of type PageFormat
* @param page
* a value of type int
* @return a value of type int
*/
public int print(Graphics g, PageFormat pageFormat, int page) {
//--- Create the Graphics2D object
Graphics2D g2d = (Graphics2D) g;
//--- Translate the origin to 0,0 for the top left corner
g2d.translate(pageFormat.getImageableX(), pageFormat
.getImageableY());
//--- Set the drawing color to black
g2d.setPaint(Color.black);
//--- Draw a border arround the page using a 12 point border
g2d.setStroke(new BasicStroke(4));
Rectangle2D.Double border = new Rectangle2D.Double(0, 0, pageFormat
.getImageableWidth(), pageFormat.getImageableHeight());
g2d.draw(border);
//--- Create a string and assign the text
String text = new String();
text += "Manipulating raw fonts would be too complicated to render paragraphs of ";
text += "text. Trying to write an algorithm to fully justify text using ";
text += "proportional fonts is not trivial. Adding support for international ";
text += "characters adds to the complexity. That's why we will use the ";
text += "<code>TextLayout</code> and the <code>LineBreakMeasurer<code> class to ";
text += "render text. The <code>TextLayout<code> class offers a lot of ";
text += "functionality to render high quality text. This class is capable of ";
text += "rendering bidirectional text such as Japanese text where the alignment ";
text += "is from right to left instead of the North American style which is left ";
text += "to right. The <code>TextLayout<code> class offers some additional ";
text += "functionalities that we will not use in the course of this ";
text += "series. Features such as text input, caret positionning and hit ";
text += "testing will not be of much use when printing documents, but it's good ";
text += "to know that this functionality exists. ";
text += "The <code>TextLayout</code> class will be used to layout ";
text += "paragraphs. The <code>TextLayout</code> class does not work alone. To ";
text += "layout text within a specified width it needs the help of the ";
text += "<code>LineBreakMeasurer</code> class. This class will wrap a string of ";
text += "text to fit a predefined width. Since it's a multi-lingual class, it ";
text += "knows exactly where to break a line of text according to the rules ";
text += "of the language. Then again the <code>LineBreakMeasurer</code> does ";
text += "not work alone. It needs information from the ";
text += "<code>FontRenderContext</code> class. This class' main function is to ";
text += "return accurate font metrics. To measure text effectively, this class ";
text += "needs to know the rendering hints for the targeted device and the font ";
text += "type being used. ";
//--- Create a point object to set the top left corner of the
// TextLayout object
Point2D.Double pen = new Point2D.Double(0.25 * POINTS_PER_INCH,
0.25 * POINTS_PER_INCH);
//--- Set the width of the TextLayout box
double width = 8 * POINTS_PER_INCH;
//--- Create an attributed string from the text string. We are
// creating an
//--- attributed string because the LineBreakMeasurer needs an
// Iterator as
//--- parameter.
AttributedString paragraphText = new AttributedString(text);
//--- Set the font for this text
paragraphText.addAttribute(TextAttribute.FONT, new Font("serif",
Font.PLAIN, 12));
//--- Create a LineBreakMeasurer to wrap the text for the
// TextLayout object
//--- Note the second parameter, the FontRendereContext. I have set
// the second
//--- parameter antiAlised to true and the third parameter
// useFractionalMetrics
//--- to true to get the best possible output
LineBreakMeasurer lineBreaker = new LineBreakMeasurer(paragraphText
.getIterator(), new FontRenderContext(null, true, true));
//--- Create the TextLayouts object
TextLayout layout;
TextLayout justifyLayout;
//--- Create a Vector to temporaly store each line of text
Vector lines = new Vector();
//--- Get the output of the LineBreakMeasurer and store it in a
// Vector
while ((layout = lineBreaker.nextLayout((float) width)) != null) {
lines.add(layout);
}
//--- Scan each line of the paragraph and justify it except for the
// last line
for (int i = 0; i < lines.size(); i++) {
//--- Get the line from the vector
layout = (TextLayout) lines.get(i);
//--- Check for the last line. When found print it
//--- with justification off
if (i != lines.size() - 1)
justifyLayout = layout.getJustifiedLayout((float) width);
else
justifyLayout = layout;
//--- Align the Y pen to the ascend of the font, remember that
//--- the ascend is origin (0, 0) of a font. Refer to figure 1
pen.y += justifyLayout.getAscent();
//--- Draw the line of text
justifyLayout.draw(g2d, (float) pen.x, (float) pen.y);
//--- Move the pen to the next position adding the descent and
//--- the leading of the font
pen.y += justifyLayout.getDescent()
+ justifyLayout.getLeading();
}
//--- Validate the page
return (PAGE_EXISTS);
}
}
} // Example5
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