Servlet登陆实例，用户登陆是我们程序员经常遇到的，对于初学者来说可能会是一个难题，以下为大家展示了简单的Servlet登陆实例源码，其中包括设置页面编码方式，支持中文显示防止乱码等：
Login_Servlet.java
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class Login_Servlet extends HttpServlet {
public Login_Servlet() {
super();
}
public void destroy() {
super.destroy();
}
public void doDelete(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType(“text/html”);
//设置页面编码方式，支持中文显示
response.setCharacterEncoding(“utf-8″);
PrintWriter out = response.getWriter();
out.println(“<!DOCTYPE HTML PUBLIC \”-//W3C//DTD HTML 4.01 Transitional//EN\”>”);
out.println(“<HTML>”);
out.println(” <HEAD><TITLE>A Servlet</TITLE></HEAD>”);
out.println(” <BODY>”);
out.println(” <form method=’get’ action=’Method_Service’>”);
out.println(” 用户名：”);
out.println(” <input type=’text’ name =’username’><br>”);
out.println(” 密码：”);
out.println(” <input type=’password’ name =’password’><br>”);
out.println(” <input type=’submit’ value =’登陆’><br>”);
out.println(” <input type=’reset’ value =’取消’><br>”);
out.println(” </form>”);
out.println(” </BODY>”);
out.println(“</HTML>”);
out.flush();
out.close();
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
}
public void init() throws ServletException {
}
}
Method_Service.java文件源码：
package com.cn.service;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
public class Method_Service extends HttpServlet {
public Method_Service() {
super();
}
public void destroy() {
super.destroy();
}
public void doDelete(HttpServletRequest request,
HttpServletResponse response) throws ServletException, IOException {
}
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType(“text/html”);
// 设置页面编码方式，支持中文显示
response.setCharacterEncoding(“utf-8″);
PrintWriter out = response.getWriter();
out.println(“<!DOCTYPE HTML PUBLIC \”-//W3C//DTD HTML 4.01 Transitional//EN\”>”);
out.println(“<HTML>”);
out.println(” <HEAD><TITLE>A Servlet</TITLE></HEAD>”);
out.println(” <BODY>”);
String username = (String) request.getParameter(“username”);
String password = (String)request.getParameter(“password”);
out.print(” 用户名: “+username+”<br>”);
out.print(” 密码: “+password+”<br>”);
out.println(” 调用了doGet方法”);
out.println(” </BODY>”);
out.println(“</HTML>”);
out.flush();
out.close();
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
response.setContentType(“text/html”);
// 设置页面编码方式，支持中文显示
response.setCharacterEncoding(“utf-8″);
PrintWriter out = response.getWriter();
out.println(“<!DOCTYPE HTML PUBLIC \”-//W3C//DTD HTML 4.01 Transitional//EN\”>”);
out.println(“<HTML>”);
out.println(” <HEAD><TITLE>A Servlet</TITLE></HEAD>”);
out.println(” <BODY>”);
String username = (String) request.getParameter(“username”);
String password = (String)request.getParameter(“password”);
out.print(” 用户名: “+username+”<br>”);
out.print(” 密码: “+password+”<br>”);
out.println(” 调用了doPost方法”);
out.println(” </BODY>”);
out.println(“</HTML>”);
out.flush();
out.close();
}
public void init() throws ServletException {
// Put your code here
}
}
web.xml配置文件：
<?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”>
<servlet>
<servlet-name>Method_Service</servlet-name>
<servlet-class>com.cn.service.Method_Service</servlet-class>
</servlet>
<servlet>
<servlet-name>Login_Servlet</servlet-name>
<servlet-class>com.cn.service.Login_Servlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>Method_Service</servlet-name>
<url-pattern>/Method_Service</url-pattern>
</servlet-mapping>
<servlet-mapping>
<servlet-name>Login_Servlet</servlet-name>
<url-pattern>/Login_Servlet</url-pattern>
</servlet-mapping>
</web-app>