JSP(java  server  page

<%! Int i=1%>成员变量

jsp页面中插入java代码

<html>

<head> <head>

<body>

<% for(int i=0;i<10;i++){ %>

<h3><%=i%></h3>

<% } %>

</body>

</html>

<html>

<head></head>

<body>

<table>

<%

String name[]={"zhangsan","luming","liuming","wangwu","lisi"};

String age[]={"23","24","56","67","24"};

for(int i=0;i<name.length;i++){

%>

<tr>

<td><%=name[i]%></td>

<td><%=age[i]%></td>

</tr>

<%

}

%>

</table>

</body>

</html>

jsp中如何导入包

<%@page import="java.util.*"%>

如何把servlet数据带入jsp

///////////////////////////////////////////////////Hashmap   put      get

页面的跳转:

说明:

首先要在webapps里面建立一个文件夹,命名为:two

two文件夹下面建立一个:WEB-INF文件夹,RegisterPage.html,  RegisterOutPage.jsp   .

然后在WEB-INF文件夹里面建立:classes文件夹,web.xml(配置文件),  data.txt(存入数据文件)。

最后在classes文件夹里面建立:RegisterPage,java

1RegisterPage,java

package com.android;

import java.io.*;

import javax.servlet.*;

import javax.servlet.http.*;

public class RegisterPage extends HttpServlet{

public void init(){

}

public void doGet(HttpServletRequest request,HttpServletResponse response) throws IOException,ServletException{

}

public void doPost(HttpServletRequest request,HttpServletResponse response) throws IOException,ServletException{

String user = request.getParameter("user");

String password = request.getParameter("password");

String confirmpassword = request.getParameter("confirmpassword");

response.setContentType("text/html;charset=gbk");

PrintWriter writer = response.getWriter();

if(!password.equals(confirmpassword)){

writer.print("两次输入的密码不一致");

}

else{

BufferedReader reader = new BufferedReader(new FileReader("D:\\tomcat\\apache-tomcat-7.0.29\\webapps\\two\\WEB-INF\\data.txt"));

String line = "";

boolean flag = false;

while((line = reader.readLine()) != null){

String arr [] = line.split("[ ]+");

if(user.equals(arr[0])){

flag = true;

writer.print("用户名已经存在");

break;

}

}

reader.close();

if(!flag){

RandomAccessFile raf = new RandomAccessFile("D:\\tomcat\\apache-tomcat-7.0.29\\webapps\\two\\WEB-INF\\data.txt","rw");

raf.seek(raf.length());

String s = "\n" + user + " " + password;

raf.write(s.getBytes());

raf.close();

// writer.print("注册成功");

RequestDispatcher rd=request.getServletContext().getRequestDispatcher("/RegisterOutPage.jsp");

rd.forward(request,response);

}

}

}

public void destory(){

}

}

(2)Web.xml

<?xml version="1.0" encoding="ISO-8859-1"?>

<web-app 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_3_0.xsd"

  version="3.0"

  metadata-complete="true">

  <servlet>

  <servlet-name>RegisterPage</servlet-name>

  <servlet-class>com.android.RegisterPage</servlet-class>

  </servlet>

  <servlet-mapping>

   <servlet-name>RegisterPage</servlet-name>

   <url-pattern>/register</url-pattern>

  </servlet-mapping>

 (3)RegisterPage.html

<html>

<head>

<title>

我的第一个注册页面

</title>

</head>

<body>

<form action="register" method="POST">

<table>

<tr>

<td>用户名:</td>

<td><input type="text" name="user" /></td>

</tr>

<tr>

<td>密码:</td>

<td><input type="password" name="password" /></td>

</tr>

<tr>

<td>确认密码:</td>

<td><input type="password" name="confirmpassword" /></td>

<td><input type="submit" name="submit" value="注册"></td>

</tr>

</table>

</form>

</body>

</html>

 (4)RegisterOutPage.jsp

<html>

<head></head>

<body>

<form>

<table>

<%

String user=(String)request.getAttribute("user");

String password=(String)request.getAttribute("password");

%>

<tr>

<td>user:<td>

<td><%=user%><td>

</tr>

<tr>

<td>password:<td>

<td><%=password%><td>

</tr>

</table>

</form>

</body>

</html>

此四个文件准备好后,对RegisterPage.java进行编译

命令:javac -d . RegisterPage.java

编译完成后,启动tomcat,启动成功后,在浏览器地址栏里面输入地址,连接到注册页面,在里面输入成功后,点击注册:

最后显示页面如下所示: