j_panel.java

将前缀表达式转为中缀表达式

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 */

package pro;
import java.awt.*; 
import java.awt.event.*; 
import javax.swing.*;
import java.awt.image.BufferedImage;
import java.io.File;
import javax.imageio.ImageIO;

/**
 *
 * @author Administrator
 */

public class J_Panel extends JPanel                                  
  {
        public BufferedImage P_back;
  	public J_Panel()
  	{
  		try
  		{
  	    File f=new File("4.jpg");
  	    P_back=ImageIO.read(f);
  	  }
  	  catch(Exception e)
  	  {
  	  }
  	}
  	protected void paintComponent(Graphics g)
  	{
  		g.drawImage(P_back,0,0,640,500,null);
  	}
  }