java servlet实现验证码
2018-02-08 17:48
351 查看
servlet 代码:
Java代码
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.util.Random;
import java.awt.*;
import java.awt.image.*;
import javax.imageio.*;
import javax.jms.Session;
public class SafeCode extends HttpServlet {
//产生随即的字体
private Font getFont() {
Random random = new Random();
Font font[] = new Font[5];
font[0] = new Font("Ravie", Font.PLAIN, 24);
font[1] = new Font("Antique Olive Compact", Font.PLAIN, 24);
font[2] = new Font("Forte", Font.PLAIN, 24);
font[3] = new Font("Wide Latin", Font.PLAIN, 24);
font[4] = new Font("Gill Sans Ultra Bold", Font.PLAIN, 24);
return font[random.nextInt(5)];
}
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
// 设置响应头 Content-type类型
resp.setContentType("image/jpeg");
// 以下三句是用于设置页面不缓存
resp.setHeader("Pragma", "No-cache");
resp.setHeader("Cache-Control", "No-cache");
resp.setDateHeader("Expires", 0);
OutputStream os = resp.getOutputStream();
int width = 83, height = 30;
// 建立指定宽、高和BufferedImage对象
BufferedImage image = new BufferedImage(width, height,BufferedImage.TYPE_INT_RGB);
Graphics g = image.getGraphics(); // 该画笔画在image上
Color c = g.getColor(); // 保存当前画笔的颜色,用完画笔后要回复现场
g.fillRect(0, 0, width, height);
char[] ch = "abcdefghjkmnpqrstuvwxyz23456789".toCharArray(); // 随即产生的字符串 不包括 i l(小写L) o(小写O) 1(数字1)0(数字0)
int length = ch.length; // 随即字符串的长度
String sRand = ""; // 保存随即产生的字符串
Random random = new Random();
for (int i = 0; i < 4; i++) {
// 设置字体
g.setFont(getFont());
// 随即生成0-9的数字
String rand = new Character(ch[random.nextInt(length)]).toString();
sRand += rand;
// 设置随机颜色
g.setColor(new Color(random.nextInt(255), random.nextInt(255), random.nextInt(255)));
g.drawString(rand, 20 * i + 6, 25);
}
//产生随即干扰点
for (int i = 0; i < 20; i++) {
int x1 = random.nextInt(width);
int y1 = random.nextInt(height);
g.drawOval(x1, y1, 2, 2);
}
g.setColor(c); // 将画笔的颜色再设置回去
g.dispose();
//将验证码记录到session
req.getSession().setAttribute("safecode", sRand);
// 输出图像到页面
ImageIO.write(image, "JPEG", os);
}
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
doGet(req, resp);
}
}
xml 代码:
Xml代码
<</span>servlet>
<</span>servlet-name>code</</span>servlet-name>
<</span>servlet-class>SafeCode</</span>servlet-class>
</</span>servlet>
<</span>servlet-mapping>
<</span>servlet-name>code</</span>servlet-name>
<</span>url-pattern>/servlet/safecode</</span>url-pattern>
</</span>servlet-mapping>
jsp代码:
Jsp代码
Java代码
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import java.util.Random;
import java.awt.*;
import java.awt.image.*;
import javax.imageio.*;
import javax.jms.Session;
public class SafeCode extends HttpServlet {
//产生随即的字体
private Font getFont() {
Random random = new Random();
Font font[] = new Font[5];
font[0] = new Font("Ravie", Font.PLAIN, 24);
font[1] = new Font("Antique Olive Compact", Font.PLAIN, 24);
font[2] = new Font("Forte", Font.PLAIN, 24);
font[3] = new Font("Wide Latin", Font.PLAIN, 24);
font[4] = new Font("Gill Sans Ultra Bold", Font.PLAIN, 24);
return font[random.nextInt(5)];
}
protected void doGet(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
// 设置响应头 Content-type类型
resp.setContentType("image/jpeg");
// 以下三句是用于设置页面不缓存
resp.setHeader("Pragma", "No-cache");
resp.setHeader("Cache-Control", "No-cache");
resp.setDateHeader("Expires", 0);
OutputStream os = resp.getOutputStream();
int width = 83, height = 30;
// 建立指定宽、高和BufferedImage对象
BufferedImage image = new BufferedImage(width, height,BufferedImage.TYPE_INT_RGB);
Graphics g = image.getGraphics(); // 该画笔画在image上
Color c = g.getColor(); // 保存当前画笔的颜色,用完画笔后要回复现场
g.fillRect(0, 0, width, height);
char[] ch = "abcdefghjkmnpqrstuvwxyz23456789".toCharArray(); // 随即产生的字符串 不包括 i l(小写L) o(小写O) 1(数字1)0(数字0)
int length = ch.length; // 随即字符串的长度
String sRand = ""; // 保存随即产生的字符串
Random random = new Random();
for (int i = 0; i < 4; i++) {
// 设置字体
g.setFont(getFont());
// 随即生成0-9的数字
String rand = new Character(ch[random.nextInt(length)]).toString();
sRand += rand;
// 设置随机颜色
g.setColor(new Color(random.nextInt(255), random.nextInt(255), random.nextInt(255)));
g.drawString(rand, 20 * i + 6, 25);
}
//产生随即干扰点
for (int i = 0; i < 20; i++) {
int x1 = random.nextInt(width);
int y1 = random.nextInt(height);
g.drawOval(x1, y1, 2, 2);
}
g.setColor(c); // 将画笔的颜色再设置回去
g.dispose();
//将验证码记录到session
req.getSession().setAttribute("safecode", sRand);
// 输出图像到页面
ImageIO.write(image, "JPEG", os);
}
protected void doPost(HttpServletRequest req, HttpServletResponse resp)
throws ServletException, IOException {
doGet(req, resp);
}
}
xml 代码:
Xml代码
<</span>servlet>
<</span>servlet-name>code</</span>servlet-name>
<</span>servlet-class>SafeCode</</span>servlet-class>
</</span>servlet>
<</span>servlet-mapping>
<</span>servlet-name>code</</span>servlet-name>
<</span>url-pattern>/servlet/safecode</</span>url-pattern>
</</span>servlet-mapping>
jsp代码:
Jsp代码
相关文章推荐
- Java 验证码
- java&nbsp;学习:在java中实现小数的精…
- java 实现运行dos命令
- Java 实现缓存机制
- Servlet技术实现动态图片验证码(Java)
- java web开发:servlet中图形验证码功能的实现
- javaEE servlet-02
- java使用servlet实现验证码
- [JavaWeb]Servlet验证码实现(实例代码)
- [分享]Java 线程池的原理与实现
- Java 实现树结构
- 纯JAVA技术验证码生成器(服务器端servlet实现)
- java 实现 日历 效果
- JavaWEB之Servlet实现验证码
- java实现&nbsp;tfidf
- 关于javaee servlet的跳转与重定向
- JAVA 实现漂浮效果
- java 使用servlet 实现验证码
- java 实现指定文件的复制和 拷贝
- java TCP实现聊天