java 如何把源码导出为jar包，以及如何使用导出的jar包

1.新建java project，编写源码如下：

package baseTest;

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

public class DrawLineFrame {public static void main (String [] args){ JFrame window = new DrawFrame(); window.setTitle("绘制图形"); window.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); window.setBounds(100,100,600,400); window.setVisible(true);}}

//窗口类class DrawFrame extends JFrame{ /** * */ private static final long serialVersionUID = 1L;

public DrawFrame(){

add(new DrawComponent()); pack(); }}

//图形类class DrawComponent extends JComponent{ /** * */ private static final long serialVersionUID = 1L; private static final int DEAFULT_WIDTH = 400; private static final int DEFAULT_HEIGHT = 400; public void paintComponent(Graphics g){ Graphics2D g2 = (Graphics2D)g; //绘制矩形 double leftx = 100; double topy = 100; double width = 200; double height = 150; Rectangle2D rect = new Rectangle2D.Double(leftx,topy ,width,height); g2.draw(rect);

//绘制椭圆 Ellipse2D ellipse = new Ellipse2D.Double(); ellipse.setFrame(rect); g2.draw(ellipse); //绘制直线 g2.draw(new Line2D.Double(leftx,topy,leftx + width ,topy + height)); //画正圆 double centerx = rect.getCenterX(); double centery = rect.getCenterY(); double radius = 150; Ellipse2D circle = new Ellipse2D.Double(); circle.setFrameFromCenter(centerx, centery,centerx+radius,centery+radius); g2.draw(circle); }}

2.运行，run as application,如果没有什么错误，导出jar包。

右键点击项目，export -->java --->jar files-->填写jar包的保存路径-->finish

3.新建新的java project,新建一个主main所在的类，

右键点击项目，Build Path-->Config Build Path--->add external jar--->选择刚才生成的jar包，---->apply-确定

在新工程中编写如下代码：

package testjar;public class testjar {

public static void main(String[] args) {

baseTest.DrawLineFrame.main(args); }

}

运行一下，就可以了