【求助】关于新人学习Servlet遇到的一些问题~

七十八号运输舰 2017-01-24 05:06:19

今天根据教程写了一些代码，三份一模一样的代码，其中一组能够顺利写入数据，其他两组分别报错404和500，请各位前辈帮忙看一下，多谢！

package web;



import java.io.IOException;

import java.io.PrintWriter;

import java.sql.Connection;

import java.sql.DriverManager;

import java.sql.PreparedStatement;

import java.sql.SQLException;



import javax.servlet.ServletException;

import javax.servlet.http.HttpServlet;

import javax.servlet.http.HttpServletRequest;

import javax.servlet.http.HttpServletResponse;



public class addEmpServlet extends HttpServlet{

	public void service(HttpServletRequest 

			request,HttpServletResponse 

			response)throws ServletException,

			IOException{

		request.setCharacterEncoding("utf-8");

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

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

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

		response.setContentType("text/html;charset=utf-8");

		PrintWriter out = response.getWriter();

		out.println(name+","+age+","+salary);

		

		Connection conn= null;

		PreparedStatement prep=null;

		try {

			Class.forName("com.mysql.jdbc.Driver");

			conn = DriverManager.getConnection("jdbc:mysql://localhost:3306/jsd1507db","root","root");

			prep = conn.prepareStatement(

					"INSERT INTO " +

					"emp(name,salary,age) " +

					"VALUES(?,?,?)");

			prep.setString(1, name);

			prep.setDouble(2, Double.parseDouble(salary));

			prep.setInt(3, Integer.parseInt(age));

			prep.executeUpdate();

			out.println("添加成功");

		} catch (Exception e) {

			 

			e.printStackTrace();

			out.println("稍后重试");

		}finally{

			if(conn!=null){

				try {

					conn.close();

				} catch (SQLException e) {

					e.printStackTrace();

				}

			}

		}

				

	}

}

<html>

	<head>

		<!-- 模拟content-type消息头 -->

		<meta http-equiv="content-type" 

		content="text/html;charset=utf-8">

	</head>

	<body style="font-size:30px;">

		<form action="2" method="post">

			<fieldset>

				<legend>添加员工</legend>

				姓名:<input name="name"/><br/>

				薪水:<input name="salary"/><br/>

				年龄:<input name="age"/><br/>

				<input type="submit" 

				value="确定"/>

			</fieldset>

		</form>

	</body>

</html>

<?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>1</servlet-name>

		<servlet-class>web.addEmpServlet</servlet-class>

	</servlet>

	<servlet-mapping>

		<servlet-name>1</servlet-name>

		<url-pattern>/2</url-pattern>

	</servlet-mapping>

</web-app>

...全文