图片验证码

 java画图：

package createImage;

import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.image.BufferedImage;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;

import javax.imageio.ImageIO;

public class CreateImage {

	/**
	 * 关于图片的类：Image、ImageIO、BufferedImage、Icon、ImageIcon
	 * @param args
	 * @throws Exception 
	 * @throws FileNotFoundException 
	 */
	public static void main(String[] args) throws FileNotFoundException, Exception {
		//获得图片缓冲区
		BufferedImage bi = new BufferedImage(150, 70, BufferedImage.TYPE_INT_RGB);
		
		//得到绘制环境
		Graphics2D g2 = (Graphics2D)bi.getGraphics();
		
		g2.setColor(Color.white);//设置颜色
		g2.fillRect(0, 0, 150, 70);//填充整张图,相当于背景色
		
		//相当于设置边框
		g2.setColor(Color.RED);
		g2.drawRect(0, 0, 150-1, 70-1);
		
		g2.setFont(new Font("宋体", Font.BOLD, 18));//设置字体样式
		g2.setColor(Color.BLACK);//设置字体颜色
		
		g2.drawString("HelloWord", 3, 50);//在图片上写字符串
		
		ImageIO.write(bi, "JPEG", new FileOutputStream("D:/word/a.jpg"));//把缓冲区里面的图片写入到指定文件下
	}
}