JSP登录验证码生成的源代码

jsp登陆验证码生成源代码 ，java import java.awt.image.*; import javax.servlet.*; import javax.servlet.http.*; import javax.imageio.*; import com.sun.image.codec.jpeg.*; import com.sun.image.codec.jpeg.JPEGCodec; public class BuildImageServlet extends HttpServlet { private Random generator = new Random(); private Color getRandColor(int fc, int bc) { //给定范围获得随机颜色 Random random = new Random(); if (fc > 255) { fc = 255; } if (bc > 255) { bc = 255; } int r = fc + random.nextInt(bc - fc); int g = fc + random.nextInt(bc - fc); int b = fc + random.nextInt(bc - fc); return new Color(r, g, b); } 。。。。