一个Servlet替代项目所有的servet

在实际的项目开发中,如果没有用到struts 而是选择了Servlet。这个时候不免要创建很多的Servlet,并且在servlet中实现doget(),doPost()方法,然后再根据需求创建方法。而方法则需要经过很多的if else 语句。这不免有点让人烦感。下面这三段代码则实现了,项目仅创建一个Servlet轻松搞定所有的业务。也更加体现了面向对象的思想。
首先创建一个基类:
package com.heavan.base;

import java.io.IOException;
import java.lang.reflect.Method;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class BaseServlet extends HttpServlet {
/**
*
*/
private static final long serialVersionUID = 1L;

public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
//获取类的全路径以及名称
String className = request.getParameter("className");
                  //获取方法名
String methodName = request.getParameter("method");
try {
                           //获取class文件
Class<?> class1 = Class.forName(className);
//获取该类所需求的方法
                           Method method = class1.getDeclaredMethod(methodName,HttpServletRequest.class,HttpServletResponse.class);
method.invoke(class1.newInstance(), request,response);//方法的实现
} catch (Exception e) {
e.printStackTrace();
}
}

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

创建一个用于Book类    (不是Servlet)
package com.heavan.book;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

public class Book {

private String name;

public String getName() {
return name;
}

public void setName(String name) {
this.name = name;
}
public void addBook(HttpServletRequest request ,HttpServletResponse response){
System.out.println("haha");
System.out.println(request.getParameter("username"));
}


}


现在要实现图书的添加功能(如何实现那?)


一个灵活的方法解决问题:
前台页面:
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
  <head>
    <base href="<%=basePath%>">
   
    <title>My JSP 'book' starting page</title>
   
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">   
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
  </head>
 
  <body>
  <form action="<%=path %>/servlet/BaseServlet" method="post">
  <input type="hidden" name="className" value="com.heavan.book.Book"><!--这个要注意噢!-->
  <input type="hidden" name="method" value="addBook">
  <input type="text" name="username">
  <input type="submit" value="submit">
  </form>
  </body>
</html>


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