MainClass.java Source code

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Here is the source code for MainClass.java

Source

import org.eclipse.swt.SWT;
import org.eclipse.swt.graphics.GC;
import org.eclipse.swt.graphics.Point;
import org.eclipse.swt.graphics.Rectangle;
import org.eclipse.swt.printing.PrintDialog;
import org.eclipse.swt.printing.Printer;
import org.eclipse.swt.printing.PrinterData;
import org.eclipse.swt.widgets.Display;
import org.eclipse.swt.widgets.MessageBox;
import org.eclipse.swt.widgets.Shell;

public class MainClass {
    public static void main(String[] args) {
        Display display = new Display();
        Shell shell = new Shell(display);

        PrintDialog dialog = new PrintDialog(shell);
        PrinterData printerData = dialog.open();
        if (printerData != null) {
            // Create the printer
            Printer printer = new Printer(printerData);

            try {
                // Print the contents of the file
                new WrappingPrinter(printer).print();
            } catch (Exception e) {
                MessageBox mb = new MessageBox(shell, SWT.ICON_ERROR | SWT.OK);
                mb.setMessage(e.getMessage());
                mb.open();
            }

            // Dispose the printer
            printer.dispose();
        }

        while (!shell.isDisposed()) {
            if (!display.readAndDispatch()) {
                display.sleep();
            }
        }
        display.dispose();
    }
}

/**
 * This class performs the printing, wrapping text as necessary Code revised
 * from /* The Definitive Guide to SWT and JFace by Robert Harris and Rob Warner
 * Apress 2004
 */

class WrappingPrinter {
    private Printer printer; // The printer

    private String fileName; // The name of the file to print

    private String contents; // The contents of the file to print

    private GC gc; // The GC to print on

    private int xPos, yPos; // The current x and y locations for print

    private Rectangle bounds; // The boundaries for the print

    private StringBuffer buf; // Holds a word at a time

    private int lineHeight; // The height of a line of text

    /**
     * WrappingPrinter constructor
     * 
     * @param printer
     *          the printer
     * @param fileName
     *          the fileName
     * @param contents
     *          the contents
     */
    WrappingPrinter(Printer printer) {
        this.printer = printer;
        this.fileName = "yourfilename.txt";
        this.contents = "long content to wrap";
    }

    /**
     * Prints the file
     */
    void print() {
        // Start the print job
        if (printer.startJob(fileName)) {
            // Determine print area, with margins
            bounds = computePrintArea(printer);
            xPos = bounds.x;
            yPos = bounds.y;

            // Create the GC
            gc = new GC(printer);

            // Determine line height
            lineHeight = gc.getFontMetrics().getHeight();

            // Determine tab width--use three spaces for tabs
            int tabWidth = gc.stringExtent(" ").x;

            // Print the text
            printer.startPage();
            buf = new StringBuffer();
            char c;
            for (int i = 0, n = contents.length(); i < n; i++) {
                // Get the next character
                c = contents.charAt(i);

                // Check for newline
                if (c == '\n') {
                    printBuffer();
                    printNewline();
                }
                // Check for tab
                else if (c == '\t') {
                    xPos += tabWidth;
                } else {
                    buf.append(c);
                    // Check for space
                    if (Character.isWhitespace(c)) {
                        printBuffer();
                    }
                }
            }
            printer.endPage();
            printer.endJob();
            gc.dispose();
        }
    }

    /**
     * Prints the contents of the buffer
     */
    void printBuffer() {
        // Get the width of the rendered buffer
        int width = gc.stringExtent(buf.toString()).x;

        // Determine if it fits
        if (xPos + width > bounds.x + bounds.width) {
            // Doesn't fit--wrap
            printNewline();
        }

        // Print the buffer
        gc.drawString(buf.toString(), xPos, yPos, false);
        xPos += width;
        buf.setLength(0);
    }

    /**
     * Prints a newline
     */
    void printNewline() {
        // Reset x and y locations to next line
        xPos = bounds.x;
        yPos += lineHeight;

        // Have we gone to the next page?
        if (yPos > bounds.y + bounds.height) {
            yPos = bounds.y;
            printer.endPage();
            printer.startPage();
        }
    }

    /**
     * Computes the print area, including margins
     * 
     * @param printer
     *          the printer
     * @return Rectangle
     */
    Rectangle computePrintArea(Printer printer) {
        // Get the printable area
        Rectangle rect = printer.getClientArea();
        // Compute the trim
        Rectangle trim = printer.computeTrim(0, 0, 0, 0);

        // Get the printer's DPI
        Point dpi = printer.getDPI();

        // Calculate the printable area, using 1 inch margins
        int left = trim.x + dpi.x;
        if (left < rect.x)
            left = rect.x;
        int right = (rect.width + trim.x + trim.width) - dpi.x;
        if (right > rect.width)
            right = rect.width;

        int top = trim.y + dpi.y;
        if (top < rect.y)
            top = rect.y;
        int bottom = (rect.height + trim.y + trim.height) - dpi.y;
        if (bottom > rect.height)
            bottom = rect.height;

        return new Rectangle(left, top, right - left, bottom - top);
    }
}