javabean 使用 JavaBean+servlet的mvc

javabean 使用 javabean+servlet的mvc

先设置web-inf下面的web.xml设置路由了

<servlet>
        <servlet-name>
            login
        </servlet-name>
        <servlet-class>
            javaweb.javabean
        </servlet-class>
    </servlet>

    <servlet-mapping>
        <servlet-name>login</servlet-name>
        <url-pattern>/login.do</url-pattern>
    </servlet-mapping>

<%@ page language="java" import="java.util.*" pageencoding="utf-8"%>
<html>
<center>
<form method=post action="wellcom.jsp">
username<input type=text name=username>
<br><br>
password<input type=password name=password>
<br><br>
<input type=submit value="注册">
</form>
</center>
</html>

定义javabean：

package javaweb;

public class javabean {
private string username;
private string password;
public void setusername(string username)
{
this.username=username;
}
public void setpassword(string password)
{
this.password=password;
}
public string getusername()
{
return username;
}
public string getpassword()
{
return password;
}
}

<%@ page language="java" import="java.util.*" pageencoding="utf-8"%>
<html>
<jsp:usebean id="hello" class="javaweb.javabean" scope="session" />
<jsp:setproperty name="hello" property="*" />
<%
//hello.username = "myname";
%>
your username is:<%= hello.getusername() %>
<br><br>
your password is:<jsp:getproperty name="hello" property="password"/>
<br><br>

</html>

jsp + javabean + servlet (俗称的mvc结构)

import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
import com.huanlin.userinfobean;

public class helloservlet2 extends https教程ervlet {
    public void service(httpservletrequest request,
            httpservletresponse response)
            throws servletexception, ioexception {


        response.setcontenttype("text/html; charset=gbk");
        request.setcharacterencoding("gbk");

        //创建javabean的对象
        javabean bean = new javabean();
        bean.setusername( request.getparameter("username").tostrng());
        httpsession session = request.getsession();
        session.setattribute("userinfo", userinfo);

        // 前往指定的网页
       response.sendredirect("welcom.jsp")
    }
}

为了重用逻辑代码部分，外加内嵌页面java代码太多，不好管理，于是出现了jsp+javabean的两层架构。就是把逻辑代码部分提取出来，放在class里面，然后在jsp页面调用class；calss功能有点类似于webform的后台处理代码，但是本质上是完全不同的；webform的后台代码是可以直接控制asp教程x页面的服务器控件，而javabean是传输数据，或兼并处理数据，然后在jsp显示，jsp+javabean模式的两层分工很明确

补充：Jsp教程,J2EE/EJB/服务器