partb.txt

用Java写的可以画直线的小程序

import javax.swing.JFrame;
public class DrawMain {


  public static void main(String[] args){
     JFrame app = new JFrame("Line Drawings");
   
     app.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
      
     app.add( new MyDraw2() );		
   
     app.setSize(250, 250);
     app.setVisible(true);
  }
}
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以上是一个类,一下是另一个类
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import java.awt.Graphics;

import javax.swing.*;
public class MyDraw2 extends JPanel
{
	public void paintComponent( Graphics g )
	{
		int height  = getHeight();
		int width = getWidth();
		int startX, startY, endX, endY;
	
		// Draw lines from the upper left corner
		startX = 0; startY = 0;
		endX = width / 16;
		endY = height;
		for ( int i = 0; i < 15; i++ )
			g.drawLine( startX, startY + i * height / 16,
					endX + i * width / 16, endY);
		// Draw lines from the lower left corner
		startX = 0; startY = height;
		endX = width;
		endY = height - height / 16;
		for ( int i = 0; i < 15; i++ )
			g.drawLine( startX + i * width / 16, startY,
					endX, endY - i * width / 16);
		// Draw lines from the lower right corner
		startX = width; startY = height;
		endX = width - width / 16;
		endY = 0;
		for ( int i = 0; i < 15; i++ )
			g.drawLine( startX, startY - i * height / 16,
					endX - i * width / 16, endY);
		// Draw lines from the upper right corner
		startX = width; startY = 0;
		endX = 0;
		endY = height / 16;
		for ( int i = 0; i < 15; i++ )
			g.drawLine( startX - i * width / 16, startY,
					endX, endY + i * height / 16);
	}
	
}