BeanUtils数据封装与表单JavaBean
                 jopen
                 11年前
            
                    一.BeanUtils工具的解释
(1)Apache的Commons组件中,提供了一个有用的工具类BeanUtils,利用它能够方便的将表单数据值填充值Bean中;
(2)javax.servlet.ServletRequest.getParameterMap()
在ServletRequest接口中,getParameter()方法的作用在于将客户端传来的参数封装在一个Map对象中,致谢参数可以通过GET POST
方法提交;
(3)org.apache.commons.beanutils.BeanUtils.populate()
这个方法的作用是将存储在Map中的参数填入给定的一个JavaBean对象中;
BeanUtils.populate(),第一个形参是一个bean对象,也就是表单的JavaBean,第二个形参是一个Map对象,也就是存储有表单圆度的Map对象;
二.举例详解
(1)编写一个JavaBean程序类RegForm
    package my;        public class RegForm         {            private String userName;            private String password;            private String sect;            private String hobby[];            private String memo;                        public void setUserName(String s)            {                userName=s;                }            public String getUserName()            {                return userName;                }            public void setPassword(String s)            {                password=s;                }            public String getPassword()            {                return password;                }                       public void setSect(String s)            {                sect=s;                }            public String getSect()            {                return sect;                }                                 public void setHobby(String s[])            {                hobby=s;                }            public String[] getHobby()            {                return hobby;                }              public void setMemo(String s)            {                memo=s;                }            public String getMemo()            {                return memo;                }         }   (2)新建一个填写数据的表单<%@ page contentType="text/html; charset=gb2312" language="java" import="java.sql.*" errorPage="" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> <title>无标题文档</title> </head> <body> <jsp:useBean id="my" class="my.RegForm" scope="page"/> <jsp:setProperty name="my" property="*"/> //反射机制将表单自动填到‘my’表单中 <br>您的用户名是:<jsp:getProperty name="my" property="userName"/> <br>您的口令是: <jsp:getProperty name="my" property="password"/> <br>您的性别是:<jsp:getProperty name="my" property="sect"/> <br>您的爱好是: <% String h[]=my.getHobby(); if(h!=null) for(int i=0;i<h.length;i++) out.print(h[i]); %> <br>您的附言是:<jsp:getProperty name="my" property="userName"/> </body> </html>(3)新建一个Servlet程序 reformServlet处理表单
    package my;        import javax.servlet.*;        import javax.servlet.http.*;        import java.io.*;        import java.util.*;        import org.apache.commons.beanutils.*;                public class RegFormServlet extends HttpServlet         {            protected void doGet(HttpServletRequest request,HttpServletResponse response)                                 throws ServletException,java.io.IOException           {              ServletContext application=getServletContext() ;              ServletConfig config=getServletConfig() ;              response.setContentType("text/html;charset=gb2312");              PrintWriter out=response.getWriter();               HttpSession session =request.getSession();              request.setCharacterEncoding("gb2312");                            RegForm form=new RegForm();              Map  map=request.getParameterMap();              try              {                 BeanUtils.populate(form,map);              }catch(Exception e)              {                System.out.println("表单处理出错:"+e);                }                        out.print("<br>您的姓名是:"+form.getUserName());            out.print("<br>您的口令是:"+form.getPassword());            out.print("<br>您的性别是:"+form.getSect());            out.print("<br>您的爱好是:");            String h[]=form.getHobby();            if(h!=null)             for(int i=0;i<h.length;i++)               out.print(h[i]);            out.print("<br>您的附言是:"+form.getMemo());            }                       protected void doPost(HttpServletRequest request,HttpServletResponse response)                                        throws ServletException,java.io.IOException          {               doGet(request,response);            }        }   (4)还有一个创建数据的界面<%@ page contentType="text/html; charset=utf-8" language="java" import="java.sql.*" errorPage="" %> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> <html xmlns="http://www.w3.org/1999/xhtml"> <head> <meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> <title>无标题文档</title> </head> <body> <form id="form1" name="form1" method="post" action="exam.jsp"> <p>会员注册信息</p> <p>用户名: <label> <input name="userName" type="text" id="userName" /> </label> </p> <p>口令: <label> <input name="password" type="password" id="password" /> </label> </p> <p>性别: <label> <input name="sect" type="radio" value="男" checked="checked" /> </label> 男 <label> <input type="radio" name="sect" value="女" /> </label> 女</p> <p>爱好: <label> <input name="hobby" type="checkbox" id="hobby" value="篮球" /> </label> 篮球 <label> <input name="hobby" type="checkbox" id="hobby" value="排球" /> </label> 排球 <label> <input name="hobby" type="checkbox" id="hobby" value="足球" /> </label> 足球</p> <p>附言: <label> <textarea name="memo" id="memo"></textarea> </label> <label> <input type="submit" name="Submit" value="提交" /> </label> </p> </form> </body> </html>来自:http://blog.csdn.net/xlgen157387/article/details/39346121