draw2d.java

学习Java的一些基本课件和源代码 对于初学者很有帮助的

//Draw2D.java
import javax.swing.*;
import java.awt.*;
import java.awt.geom.*;

public class Draw2D extends JFrame{

	public Draw2D(){
		super("Java2D图形绘制");
		setSize(200,150);
		setVisible(true);
	}
	public void paint(Graphics g){
		super.paint(g);
		Graphics2D g2D=(Graphics2D)g;//将图形对象强制转换为Graphics2D类型
		//用红色，5.0宽的画笔绘制2D线段
		g2D.setPaint(Color.RED);
		g2D.setStroke(new BasicStroke(5.0f));
		g2D.draw(new Line2D.Float(30.5f,30.5f,30.5f,130.5f));
		
		//用蓝-黄渐变色绘制2D图形椭圆
		g2D.setPaint(new GradientPaint(5,30,Color.BLUE,35,100,Color.YELLOW,true));
		//Graphics2D类的方法，设置渐变色
		g2D.fill(new Ellipse2D.Double(45,30,65,100));
		//用绿色，10.0宽的画笔绘制2D矩形
		g2D.setPaint(Color.GREEN);
		g2D.setStroke(new BasicStroke(10.0f));
		g2D.draw(new Rectangle2D.Double(120,30,50,100));
	}
	
	public static void main(String args[])
	{
		Draw2D myDraw2D=new Draw2D();
		myDraw2D.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	}
}