其它内容都不显示，是什么原因啊，请高手赐教。验证码实现是一个java程序，用servlet调用。
验证码的servlet：
Ic.java
package com.zuxia.common;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
@SuppressWarnings("serial")
public class Ic extends HttpServlet {
/**
* Constructor of the object.
*/
public Ic() {
super();
}
/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
Color getRandColor(int fc, int bc) {
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);
}
/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("image/png");
response.setHeader("Pragma", "no-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0L);
int width = 60; int height = 20;
BufferedImage image = new BufferedImage(width, height,
1);
Graphics g = image.createGraphics();
Random random = new Random();
g.setColor(getRandColor(200, 250));
g.fillRect(0, 0, width, height);
g.setFont(new Font("DialogInput", 2, 18));
g.setColor(getRandColor(160, 200));
for (int i = 0; i < 255; i++) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x, y, x + xl, y + yl);
}
String sRand = "";
for (int i = 0; i < 4; i++) {
String rand = String.valueOf(random.nextInt(10));
sRand = sRand + rand;
g.setColor(
new Color(20 + random.nextInt(110), 20 +
random.nextInt(110), 20 + random.nextInt(110)));
g.drawString(rand, 13 * i + 6, 16);
}
HttpSession session = request.getSession();
session.setAttribute("validecode", sRand);
g.dispose();
ServletOutputStream outputstream = response.getOutputStream();
ImageIO.write(image, "PNG", outputstream);
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
}
}
配置文件：
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<!-- 配置 验证码支持-->
<servlet>
<servlet-name>Ic</servlet-name>
<servlet-class>com.zuxia.common.Ic</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Ic</servlet-name>
<url-pattern>/Ic</url-pattern>
</servlet-mapping>
</web-app>
jsp页面：
index.jsp
<%@ page language="java" import="java.util.*" pageEncoding="gbk"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'index.jsp' starting page</title>
<script type="text/javascript">
function Code(obj){
obj.src="Ic?"+Math.random();
}
</script>
</head>
<body>
<img src="Ic" alt="看不清?点击图片换一张" onclick="Code(this)"/>
</body>
</html>
Ic.java
package com.zuxia.common;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
@SuppressWarnings("serial")
public class Ic extends HttpServlet {
/**
* Constructor of the object.
*/
public Ic() {
super();
}
/**
* Destruction of the servlet. <br>
*/
public void destroy() {
super.destroy(); // Just puts "destroy" string in log
// Put your code here
}
/**
* The doGet method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to get.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doPost(request, response);
}
Color getRandColor(int fc, int bc) {
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);
}
/**
* The doPost method of the servlet. <br>
*
* This method is called when a form has its tag value method equals to post.
*
* @param request the request send by the client to the server
* @param response the response send by the server to the client
* @throws ServletException if an error occurred
* @throws IOException if an error occurred
*/
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType("image/png");
response.setHeader("Pragma", "no-cache");
response.setHeader("Cache-Control", "no-cache");
response.setDateHeader("Expires", 0L);
int width = 60; int height = 20;
BufferedImage image = new BufferedImage(width, height,
1);
Graphics g = image.createGraphics();
Random random = new Random();
g.setColor(getRandColor(200, 250));
g.fillRect(0, 0, width, height);
g.setFont(new Font("DialogInput", 2, 18));
g.setColor(getRandColor(160, 200));
for (int i = 0; i < 255; i++) {
int x = random.nextInt(width);
int y = random.nextInt(height);
int xl = random.nextInt(12);
int yl = random.nextInt(12);
g.drawLine(x, y, x + xl, y + yl);
}
String sRand = "";
for (int i = 0; i < 4; i++) {
String rand = String.valueOf(random.nextInt(10));
sRand = sRand + rand;
g.setColor(
new Color(20 + random.nextInt(110), 20 +
random.nextInt(110), 20 + random.nextInt(110)));
g.drawString(rand, 13 * i + 6, 16);
}
HttpSession session = request.getSession();
session.setAttribute("validecode", sRand);
g.dispose();
ServletOutputStream outputstream = response.getOutputStream();
ImageIO.write(image, "PNG", outputstream);
}
/**
* Initialization of the servlet. <br>
*
* @throws ServletException if an error occurs
*/
public void init() throws ServletException {
// Put your code here
}
}
配置文件：
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
<!-- 配置 验证码支持-->
<servlet>
<servlet-name>Ic</servlet-name>
<servlet-class>com.zuxia.common.Ic</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Ic</servlet-name>
<url-pattern>/Ic</url-pattern>
</servlet-mapping>
</web-app>
jsp页面：
index.jsp
<%@ page language="java" import="java.util.*" pageEncoding="gbk"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'index.jsp' starting page</title>
<script type="text/javascript">
function Code(obj){
obj.src="Ic?"+Math.random();
}
</script>
</head>
<body>
<img src="Ic" alt="看不清?点击图片换一张" onclick="Code(this)"/>
</body>
</html>
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