import java.awt.BasicStroke;
import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Component;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.GridLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;
import java.awt.print.PageFormat;
import java.awt.print.Printable;
import java.awt.print.PrinterException;
import java.awt.print.PrinterJob;
import javax.swing.JButton;
import javax.swing.JDialog;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.SwingUtilities;
import javax.swing.WindowConstants;
import javax.swing.text.BadLocationException;
import javax.swing.text.Document;
public class PrintUIComponent extends JPanel implements ActionListener,
Printable {
private static final long serialVersionUID=4797002827940419724L;
private static JFrame frame;
private JTextArea textAreaToPrint;
private PrinterJob job;
private int[] pageBreaks;// array of page break line positions
private String[] textLines;
private Header header;
public PrintUIComponent() {
super(new BorderLayout());
textAreaToPrint=new JTextArea(50, 20);
for (int i=1; i <=50; i++) {
textAreaToPrint.append(“Line ” + i + “\n”);
}
JScrollPane scrollPane=new JScrollPane(textAreaToPrint);
scrollPane.setPreferredSize(new Dimension(250, 200));
add(scrollPane, BorderLayout.CENTER);
JButton printButton=new JButton(“Print This TextArea”);
printButton.setName(“printButton”);
printButton.addActionListener(this);
JButton printPreviewButton=new JButton(“Print Preview”);
printPreviewButton.setName(“printPreviewButton”);
printPreviewButton.addActionListener(this);
JPanel buttonGroup=new JPanel(new GridLayout(2, 1));
buttonGroup.add(printButton);
buttonGroup.add(printPreviewButton);
add(buttonGroup, BorderLayout.SOUTH);
initPrinterJob();
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {
@Override
public void run() {
createAndShowGUI();
}
});
}
private static void createAndShowGUI() {
frame=new JFrame(“Print UI Example”);
frame.setContentPane(new PrintUIComponent());
frame.pack();
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
frame.setVisible(true);
}
private void initTextLines() {
Document doc=textAreaToPrint.getDocument();
try {
String text=doc.getText(0, doc.getLength());
textLines=text.split(“\n”);
} catch (BadLocationException e) {
e.printStackTrace();
}
}
private void initPrinterJob() {
job=PrinterJob.getPrinterJob();
job.setJobName(“Print TextArea”);// 出现在系统打印任务列表
job.setPrintable(this);
}
@Override
public int print(Graphics graphics, PageFormat pageFormat, int pageIndex)
throws PrinterException {
Graphics2D g2=(Graphics2D) graphics.create();
Font font=new Font(“Serif”, Font.PLAIN, 12);
FontMetrics metrics=g2.getFontMetrics(font);
int lineHeight=metrics.getHeight();
if (pageBreaks==null) {
initTextLines();
int linesPerPage=(int) (pageFormat.getImageableHeight() / lineHeight);
int numBreaks=(textLines.length – 1) / linesPerPage;
pageBreaks=new int[numBreaks];
for (int b=0; b < numBreaks; b++) {
pageBreaks[b]=(b + 1) * linesPerPage;
}
}
if (pageIndex > pageBreaks.length) {
return NO_SUCH_PAGE;
}
g2.translate(pageFormat.getImageableX(), pageFormat.getImageableY());
int y=0;
int start=(pageIndex==0) ? 0 : pageBreaks[pageIndex – 1];
int end=(pageIndex==pageBreaks.length) ? textLines.length
: pageBreaks[pageIndex];
for (int line=start; line < end; line++) {
y +=lineHeight;
g2.drawString(textLines[line], 0, y);
}
g2.dispose();
return PAGE_EXISTS;
}
@Override
public void actionPerformed(ActionEvent e) {
Object actionEventSource=e.getSource();
if (actionEventSource instanceof JButton) {
JButton button=(JButton) actionEventSource;
if (button.getName().equals(“printButton”)) {
pageBreaks=null;// reset pagination
boolean ok=job.printDialog();
if (ok) {
try {
job.print();
} catch (PrinterException ex) {
ex.printStackTrace();
}
}
} else if (button.getName().equals(“printPreviewButton”)) {
pageBreaks=null;// reset pagination
createAndShowPreviewDialog();
}
}
}
private void createAndShowPreviewDialog() {
JDialog previewDialog=new JDialog(frame, “Print Preview Dialog”, true);
JPanel contentPane=new JPanel(new BorderLayout());
PreviewArea previewArea=new PreviewArea();
previewArea.addMouseListener(new PreviewAreaMouseAdapter(previewArea));
JScrollPane scrollPane=new JScrollPane(previewArea);
contentPane.add(scrollPane, BorderLayout.CENTER);
header=new Header(previewArea);
contentPane.add(header, BorderLayout.NORTH);
previewDialog.setContentPane(contentPane);
previewDialog.setSize(600, 600);
previewDialog
.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
previewDialog.setVisible(true);
}
private class Header extends Component {
private static final long serialVersionUID=-1741188309769027249L;
private PreviewArea previewArea;
private boolean paintable;
private Header(PreviewArea previewArea) {
this.previewArea=previewArea;
}
private void setPaintable(boolean paintable) {
this.paintable=paintable;
}
@Override
public void paint(Graphics g) {
if (paintable) {
g.setColor(Color.GRAY);
g.drawString(
String.valueOf(previewArea.getPageIndex() + 1)
+ “/”
+ String.valueOf(pageBreaks.length + 1)
+ ” pages (Click left mouse button to preview next page; right to previous)”,
10, 15);
}
}
@Override
public Dimension getPreferredSize() {
return new Dimension(super.getPreferredSize().width, 20);
}
}
private class PreviewArea extends Component {
private static final long serialVersionUID=-6384174997251439843L;
private PageFormat pageFormat;
private int pageIndex;
private int w;
private int h;
private final int marginX=10;
private final int marginY=20;
private PreviewArea() {
pageFormat=job.pageDialog(job.defaultPage());
pageIndex=0;
w=(int) pageFormat.getWidth();
h=(int) pageFormat.getHeight();
}
private int getPageIndex() {
return pageIndex;
}
private void setPageIndex(int pageIndex) {
this.pageIndex=pageIndex;
}
@Override
public Dimension getPreferredSize() {
return new Dimension(w + 2 * marginX, h + 2 * marginY);
}
@Override
public void paint(Graphics g) {
Graphics2D g2=(Graphics2D) g.create();
g2.translate(marginX, marginY);
g2.drawRect(0, 0, w, h);
int ix=(int) (pageFormat.getImageableX() – 1);
int iy=(int) (pageFormat.getImageableY() – 1);
int iw=(int) (pageFormat.getImageableWidth() + 1);
int ih=(int) (pageFormat.getImageableHeight() + 1);
g2.setStroke(new BasicStroke(1f, BasicStroke.CAP_ROUND,
BasicStroke.JOIN_ROUND, 10f, new float[] { 5, 5 }, 0f));
g2.drawRect(ix, iy, iw, ih);
try {
PrintUIComponent.this.print(g2, pageFormat, pageIndex);
} catch (PrinterException e) {
e.printStackTrace();
}
g2.dispose();
header.setPaintable(true);
header.repaint();
}
}
private class PreviewAreaMouseAdapter extends MouseAdapter {
private PreviewArea previewArea;
private PreviewAreaMouseAdapter(PreviewArea previewArea) {
this.previewArea=previewArea;
}
@Override
public void mouseClicked(MouseEvent e) {
int currentIndex=previewArea.getPageIndex();
if (e.getButton()==MouseEvent.BUTTON1) {
if (currentIndex < pageBreaks.length) {
previewArea.setPageIndex(currentIndex + 1);
previewArea.repaint();
}
} else if (e.getButton()==MouseEvent.BUTTON3) {
if (currentIndex > 0) {
previewArea.setPageIndex(currentIndex – 1);
previewArea.repaint();
}
}
}
}
}
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