java2dline.java

本java源程序包括了大量的学习程序（共27章）方便大家学习

import javax.swing.*;
import java.awt.*;
import java.awt.geom.*;
public class Java2DLine extends JFrame
{
	public Java2DLine()
	{
		super("绘制Java2D直线");
		setSize(400, 400);   //设置窗口大小
		setVisible(true);   //设置窗口为可见
	}	
	public void paint(Graphics g)
	{
        //将Graphics对象g转化为Graphics2D对象g_2d
		Graphics2D g_2d = (Graphics2D)g;
		//设置三种线形
		BasicStroke bs1 = new BasicStroke(8f,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL);
		BasicStroke bs2 = new BasicStroke(8f,BasicStroke.CAP_ROUND,BasicStroke.JOIN_MITER);
		BasicStroke bs3 = new BasicStroke(10f,BasicStroke.CAP_SQUARE,BasicStroke.JOIN_ROUND);
		//创建三条直线对象实例
		Line2D line1 = new Line2D.Double(20,60,200,60);
		Line2D line2 = new Line2D.Double(20,80,200,80);
		Line2D line3 = new Line2D.Double(20,100,200,100);
		g_2d.setColor(Color.BLUE);  //设置线条颜色
		g_2d.setStroke(bs1);        //设置线条线形
		g_2d.draw(line1);           //画直线
		g_2d.setColor(Color.GREEN); 
		g_2d.setStroke(bs2);        
		g_2d.draw(line2);           
		g_2d.setColor(Color.RED);
		g_2d.setStroke(bs3);
		g_2d.draw(line3);
	}
	public static void main(String[] args) 
	{
		Java2DLine java2DLine = new Java2DLine();
		java2DLine.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	}
}