如何设计打印功能

Question

用java编写像windows记事本的打印功能如何设计

Answer 1

参考实现，反写一下设计吧
import   java.awt.*;   
  import   java.io.*;   
  import   java.awt.print.*;   
  import   javax.swing.*;   
  import   javax.swing.text.*;   
    
  class   PrintableTextArea   extends   JTextArea   implements   Printable   {   
      String   str;   
      Font   font;   
      PrinterJob   pj;   
      PageFormat   defaultFormat;   
      int   visiblePageWidth   =   0,   visiblePageHeight   =   0;   
      final   static   int   PageX   =   10,   PageY   =   10;   
    
      PrintableTextArea(int   rows,   int   columns)   {   
          super(rows,   columns);   
      }   
    
      public   void   printIt(String   str,   Font   font)   {   
          this.str   =   str;   
          this.font   =   font;   
          pj   =   PrinterJob.getPrinterJob();   
          defaultFormat   =   pj.defaultPage();   
          pj.setPrintable(this,   defaultFormat);   
          visiblePageWidth   =   (int)defaultFormat.getImageableWidth();   
          visiblePageHeight   =   (int)defaultFormat.getImageableHeight();   
          if(pj.printDialog())   {   
              try   {   
                  pj.print();   
              }   catch(PrinterException   e)   {   
              }   
          }   
      }   
    
      public   int   print(Graphics   g,   PageFormat   pf,   int   page)   throws   PrinterException   {   
          if(page   >=   1)   
              return   Printable.NO_SUCH_PAGE;   
          Graphics2D   g2   =   (Graphics2D)   g;   
          g2.translate((int)pf.getImageableX(),   (int)pf.getImageableY());   
          g2.setFont(font);   
          int   fontHeight   =   0,   fontStringWidth   =   0;   
          int   line   =   0;   
          String   s   =   null;   
          FontMetrics   fm   =   getFontMetrics(font);   
          fontHeight   =   fm.getHeight();   
          try{   
              DataOutputStream   osw   =   new   DataOutputStream(new   FileOutputStream("$temp.$$p"));   
              osw.writeBytes(str);   
              osw.close();   
          }   catch(IOException   e)   {   
          }   
          try   {   
              BufferedReader   br   =   new   BufferedReader(new   FileReader("$temp.$$p"));   
              s   =   br.readLine();   
              while(s   !=   null)   {   
                  if(s.length()   ==   0)   
                      g2.drawString("   ",   PageX,   PageY   +   fontHeight*(line++));   
                  else   {   
                      //g2.drawString(s,   PageX,   PageY   +   fontHeight*(line++));   
                      fontStringWidth   =   fm.stringWidth(s);   
                      if(fontStringWidth   >   visiblePageWidth)   {   
                          String   s1,   s2;   
                          int   goBack   =   0;   
                          while(   fm.stringWidth(s1   =   s.substring(0,   s.length()   -   goBack))   >   
                                        visiblePageWidth)   {   
                              goBack++;   
                          }   
                          s1   =   s.substring(0,   s.length()   -   goBack);   
                          s2   =   s.substring(s.length()   -   goBack   -   1);   
                          g2.drawString(s1,   PageX,   PageY   +   fontHeight*(line++));   
                          g2.drawString(s2,   PageX,   PageY   +   fontHeight*(line++));   
                      }   
                      else   {   
                          g2.drawString(s,   PageX,   PageY   +   fontHeight*(line++));   
                      }   
                  }   
                  s   =   br.readLine();   
              }   
              br.close();   
          }   catch(IOException   e)   {   
          }   
          return   Printable.PAGE_EXISTS;   
      }