插件生成验证码

在web工程目录中添加工具包，如图：

 

 

创建一个Servlet，代码如下：

　　注意：如果你的tomcat版本低于7.0，就没有@WebServlet("/ValidateCode")注解；

　　　　这时就需要你自己动手为Servlet类在web.xml中注册

 

package com.qf.test;

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

import cn.dsna.util.images.ValidateCode;

/**
 * Servlet implementation class ValidateCode
 */
@WebServlet("/ValidateCode")
public class ValidateCode01 extends HttpServlet {

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        ValidateCode code = new ValidateCode(300, 100, 5, 20);
        code.write(response.getOutputStream());
        String string = code.getCode();
        System.out.println("=====code===="+string);
    }

    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        // TODO Auto-generated method stub
        doGet(request, response);
    }

}

 

　　效果图：

 

　　控制台获取生成的验证码：