huaban.java

是一个课程设计时候编写的JAVA的绘图板工具

   class mouseB extends MouseMotionAdapter
      {
        public void mouseDragged(MouseEvent e)
          {statusBar.setText("     鼠标在绘画面板的移动位置:["
                          + e.getX() + ", " + e.getY() + "]");
    if(currentChoice==3||currentChoice==8)
       {
        itemList[index-1].x1=itemList[index].x2=itemList[index].x1=e.getX();
        itemList[index-1].y1=itemList[index].y2=itemList[index].y1=e.getY();
        index++;
        createNewItem();
       }
   else     {  itemList[index].x2=e.getX();
               itemList[index].y2=e.getY();
             }
       repaint();
          }
          
       public void mouseMoved(MouseEvent e)
            {statusBar.setText("     鼠标在绘画面板的位置:["
                        + e.getX() +  ", " + e.getY() + "]");
            }  
       }  
//选择字体风格时候用到的事件侦听器类，加入到字体风格的选择框中
private class checkBoxHandler implements ItemListener
    {  public void itemStateChanged(ItemEvent e)
         {if(e.getSource()==bold)
             if(e.getStateChange()==ItemEvent.SELECTED)
                  f1=Font.BOLD;
             else f1=Font.PLAIN;
             
          if(e.getSource()==italic)
             if(e.getStateChange()==ItemEvent.SELECTED)
                  f2=Font.ITALIC;
             else f2=Font.PLAIN;
         }
     }
//画图面板类，用来画图
  class DrawPanel extends JPanel
    {
     public DrawPanel(){
        setCursor(Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR));
        setBackground(Color.white);
        addMouseListener(new mouseA());
        addMouseMotionListener(new mouseB());
           }

     public void paintComponent(Graphics g)
        {  super.paintComponent(g);
           Graphics2D g2d=(Graphics2D)g;	//定义画笔
           int j=0;
           while (j<=index)
              {
              draw(g2d,itemList[j]);
              j++;
              }
        }
    void draw(Graphics2D g2d,drawings i)
          {  i.draw(g2d);} //用来完成各子类的绘图
     }
 //新建一个画图基本单元对象的程序段
 void createNewItem()
    { if(currentChoice==9) drawingArea.setCursor(
    	  Cursor.getPredefinedCursor(Cursor.TEXT_CURSOR));
          else drawingArea.setCursor(
          Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR));

   switch (currentChoice)
        {
      case 3:itemList[index]=new Pencil();break;
      case 4:itemList[index]=new Line(); break;
      case 5:itemList[index]=new Rect(); break;
      case 6:itemList[index]=new Oval();  break;
      case 7:itemList[index]=new Circle(); break;
      case 8:itemList[index]=new Rubber();break;
      case 9:itemList[index]=new Word();break;
      case 11:itemList[index]=new fillRect();break;
      case 12:itemList[index]=new fillOval();break;
      case 13:itemList[index]=new fillCircle();break;
         }
     itemList[index].type=currentChoice;
     itemList[index].R=R;
     itemList[index].G=G;
     itemList[index].B=B;
     itemList[index].brush=brush;
    }
//选择当前颜色程序段
public void chooseColor()
   {  color=JColorChooser.showDialog(Huaban.this,
                          "选择你所需要的颜色",color);
      R=color.getRed();
      G=color.getGreen();
      B=color.getBlue();
      itemList[index].R=R;
      itemList[index].G=G;
      itemList[index].B=B;
    }
//选择当前线条粗细程序段
 public void setStroke()
    {
      String input;
      input=JOptionPane.showInputDialog(
             "请输入你想要的粗度数字! ( 默认是1)");
      brush=Float.parseFloat(input);
      itemList[index].brush=brush;
     }
 //新建一个文件程序段
 public void newFile()
  {  index=0;  currentChoice=3;
    color=Color.black; brush=1.0f;
    createNewItem();
    repaint();//将有关值设置为初始状态，并且重画
   }
//保存图形文件程序段
 public void saveFile()
  {
    JFileChooser filesave=new JFileChooser();
    filesave.setFileSelectionMode(JFileChooser.FILES_ONLY);
    if(filesave.showSaveDialog(this)==JFileChooser.CANCEL_OPTION)return ;
             
    File fileName=filesave.getSelectedFile();
    fileName.canWrite();
    
   try {
       fileName.delete();
       FileOutputStream fos=new FileOutputStream(fileName);

       output=new ObjectOutputStream(fos);
       drawings record;

       output.writeInt( index );

       for(int i=0;i< index ;i++)
            {
               drawings p= itemList[ i ] ;
             output.writeObject(p);
          output.flush();//将所有图形信息强制转换成父类线性化存储到文件中
               }
         output.close();
         fos.close();
        }
          catch(Exception ioe){}
      }
 //打开一个图形文件程序段
   public void openFile()
   {
     JFileChooser fileopen=new JFileChooser();
     fileopen.setFileSelectionMode(JFileChooser.FILES_ONLY);
     int result =fileopen.showOpenDialog(this);
     if(result==JFileChooser.CANCEL_OPTION)return ;
          
    File fileName=fileopen.getSelectedFile();
    fileName.canRead();
    
      try {

          FileInputStream fis=new FileInputStream(fileName);

          input=new ObjectInputStream(fis);
          drawings inputRecord;

          int countNumber=0;
          countNumber=input.readInt();

          for(index=0;index< countNumber ;index++)
           {
            inputRecord=(drawings)input.readObject();
            itemList[ index ] = inputRecord ;
           }

          createNewItem();
          input.close();
           repaint();
          } catch(Exception e){JOptionPane.showMessageDialog(this,"读取文件格式错误",
                           "读取错误",JOptionPane.ERROR_MESSAGE );}
         }

 //主函数段
 public static void main(String args[])
  {try {
        UIManager.setLookAndFeel( UIManager.getSystemLookAndFeelClassName());
        }
     catch ( Exception e ) {}//将界面设置为当前windows风格

   Huaban newPad=new Huaban();
   newPad.addWindowListener(
        new WindowAdapter(){
           public void windowClosing(WindowEvent e)
           {System.exit(0);}});
  }
}
//定义画图的基本图形单元
class drawings implements Serializable//父类，基本图形单元，用到串行化接口，保存时所用
 {
  int x1,y1,x2,y2;	//坐标属性
  int R,G,B;	
  float brush;		//定义线条粗细属性
  int type;		//定义字体属性
  String s1;
  String s2;		//定义字体风格属性
  void draw(Graphics2D g2d){};//定义绘图函数
  
 }

// 下面是各种基本图形单元的子类，都继承自父类drawings
class Line extends drawings //直线类
  { void draw(Graphics2D g2d)
     {  g2d.setPaint(new Color(R,G,B));
        g2d.setStroke(new BasicStroke(brush,
              BasicStroke.CAP_ROUND,BasicStroke.JOIN_BEVEL));
      g2d.drawLine(x1,y1,x2,y2);
     }
   }
   
class Rect extends drawings//矩形类
   { 
 void draw(Graphics2D g2d)
       { g2d.setPaint(new Color(R,G,B));
        g2d.setStroke(new BasicStroke(brush));
         g2d.drawRect(Math.min(x1,x2),Math.min(y1,y2),
              Math.abs(x1-x2),Math.abs(y1-y2));
       }
    }

class fillRect extends drawings//实心矩形类
 {  void draw(Graphics2D g2d)
     { g2d.setPaint(new Color(R,G,B));
       g2d.setStroke(new BasicStroke(brush));
       g2d.fillRect(Math.min(x1,x2),Math.min(y1,y2),
              Math.abs(x1-x2),Math.abs(y1-y2));
      }
  }

class Oval extends drawings//椭圆类
  { void draw(Graphics2D g2d)
     { g2d.setPaint(new Color(R,G,B));
       g2d.setStroke(new BasicStroke(brush));
       g2d.drawOval(Math.min(x1,x2),Math.min(y1,y2),
                  Math.abs(x1-x2),Math.abs(y1-y2));
      }
   }

 class fillOval extends drawings//实心椭圆
   {  void draw(Graphics2D g2d)
       { g2d.setPaint(new Color(R,G,B));
         g2d.setStroke(new BasicStroke(brush));
         g2d.fillOval(Math.min(x1,x2),Math.min(y1,y2),
                Math.abs(x1-x2),Math.abs(y1-y2));
        }
    }

 class Circle extends drawings//圆类
  { void draw(Graphics2D g2d)
     { g2d.setPaint(new Color(R,G,B));
       g2d.setStroke(new BasicStroke(brush));
       g2d.drawOval(Math.min(x1,x2),Math.min(y1,y2),
               Math.max(Math.abs(x1-x2),Math.abs(y1-y2)),
               Math.max(Math.abs(x1-x2),Math.abs(y1-y2)));
      }
   }

 class fillCircle extends drawings//实心圆
  { void draw(Graphics2D g2d)
     { g2d.setPaint(new Color(R,G,B));
       g2d.setStroke(new BasicStroke(brush));
       g2d.fillOval(Math.min(x1,x2),Math.min(y1,y2),
               Math.max(Math.abs(x1-x2),Math.abs(y1-y2)),
               Math.max(Math.abs(x1-x2),Math.abs(y1-y2)));
      }
   }

 class Pencil extends drawings//随笔画类
  { void draw(Graphics2D g2d)
     { g2d.setPaint(new Color(R,G,B));
       g2d.setStroke(new BasicStroke(brush,
              BasicStroke.CAP_ROUND,BasicStroke.JOIN_BEVEL));
       g2d.drawLine(x1,y1,x2,y2);
      }
   }

 class Rubber extends drawings//橡皮擦类
   { void draw(Graphics2D g2d)
      { g2d.setPaint(new Color(255,255,255));
        g2d.setStroke(new BasicStroke(brush+4,
             BasicStroke.CAP_ROUND,BasicStroke.JOIN_BEVEL));
        g2d.drawLine(x1,y1,x2,y2);
         }
    }

class Word extends drawings//输入文字类
   {  void draw(Graphics2D g2d)
       {  g2d.setPaint(new Color(R,G,B));
          g2d.setFont(new Font(s2,x2+y2,((int)brush)*18));
          if (s1!= null )
          g2d.drawString(s1,x1,y1);
         }
    }