Eclipse三层架构项目(增删改查)

ゝ一世哀愁。 2022-03-30 06:52 390阅读 0赞

搭建好项目记得导包：

![20190105100308722.jpg][]

连接池(根据自己的配置改)：

driver=com.mysql.jdbc.Driver
    url=jdbc:mysql://localhost:3306/student?useUnicode=true&characterEncoding=utf-8&useSSL=false
    user=root
    password=994994

连接数据库工具类：

package com.accp.dao;
    
    import java.io.IOException;
    import java.io.InputStream;
    import java.sql.Connection;
    import java.sql.DriverManager;
    import java.sql.PreparedStatement;
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.util.List;
    import java.util.Properties;
    
    public class BaseDao {
    	private static String driver;
    	private static String url;
    	private static String user;
    	private static String password;
    	private Connection conn;
    	private PreparedStatement pstmt;
    	private ResultSet rs;
    	
    	static {
    		Properties params = new Properties();
    		String configFile = "database.properties";
    		InputStream is = BaseDao.class.getClassLoader().getResourceAsStream(configFile);
    		try {
    			params.load(is);
    		} catch (IOException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}
    		driver=params.getProperty("driver");
    		url=params.getProperty("url");
    		user=params.getProperty("user");
    		password=params.getProperty("password");
    	}
    	
        //连接
    	public Connection getConnection() {
    		try {
    			Class.forName(driver);
    			conn = DriverManager.getConnection(url, user, password);
    		} catch (ClassNotFoundException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		} catch (SQLException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}
    		return conn;
    	}
    
        //关闭流
    	public void closeAll() {
    		if (null != rs) {
    			try {
    				rs.close();
    			} catch (SQLException e) {
    				// TODO Auto-generated catch block
    				e.printStackTrace();
    			}
    		}
    		if (null != pstmt) {
    			try {
    				pstmt.close();
    			} catch (SQLException e) {
    				// TODO Auto-generated catch block
    				e.printStackTrace();
    			}
    		}
    		if (null != conn) {
    			try {
    				conn.close();
    			} catch (SQLException e) {
    				// TODO Auto-generated catch block
    				e.printStackTrace();
    			}
    		}
    	}
    
        //增删改
    	public int executeUpdate(String sql, Object... objects) {
    		getConnection();
    		int rows = 0;
    		try {
    			pstmt = conn.prepareStatement(sql);
    			for (int i = 0; i < objects.length; i++) {
    				pstmt.setObject(i + 1, objects[i]);
    			}
    			rows = pstmt.executeUpdate();
    		} catch (SQLException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		} finally {
    			closeAll();
    		}
    		return rows;
    	}
    
        //查询
    	public ResultSet executeQuery(String sql, List<Object> list) {
    		getConnection();
    		try {
    			pstmt = conn.prepareStatement(sql);
    			for (int i = 0; i < list.size(); i++) {
    				pstmt.setObject(i + 1, list.get(i));
    			}
    			rs = pstmt.executeQuery();
    		} catch (SQLException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}
    		return rs;
    	}
    }

实体类：

package com.accp.entity;
    
    public class StudentInfo {
    	private Integer sId;
    	private String sName;
    	private String sGender;
    	private Integer sAge;
    	private String sAddress;
    	private String sEmail;
    	public Integer getsId() {
    		return sId;
    	}
    	public void setsId(Integer sId) {
    		this.sId = sId;
    	}
    	public String getsName() {
    		return sName;
    	}
    	public void setsName(String sName) {
    		this.sName = sName;
    	}
    	public String getsGender() {
    		return sGender;
    	}
    	public void setsGender(String sGender) {
    		this.sGender = sGender;
    	}
    	public Integer getsAge() {
    		return sAge;
    	}
    	public void setsAge(Integer sAge) {
    		this.sAge = sAge;
    	}
    	public String getsAddress() {
    		return sAddress;
    	}
    	public void setsAddress(String sAddress) {
    		this.sAddress = sAddress;
    	}
    	public String getsEmail() {
    		return sEmail;
    	}
    	public void setsEmail(String sEmail) {
    		this.sEmail = sEmail;
    	}
    }

Dao层：

package com.accp.dao;
    
    import java.util.List;
    
    import com.accp.entity.StudentInfo;
    
    public interface StudentInfoDao {
    	public List<StudentInfo> select(StudentInfo si);
    	
    	public int update(StudentInfo si);
    	
    	public int delete(StudentInfo si);
    }

Dao层Impl实现类：

package com.accp.dao.impl;
    
    import java.sql.ResultSet;
    import java.sql.SQLException;
    import java.util.ArrayList;
    import java.util.List;
    
    import com.accp.dao.BaseDao;
    import com.accp.dao.StudentInfoDao;
    import com.accp.entity.StudentInfo;
    
    public class StudentInfoDaoImpl extends BaseDao implements StudentInfoDao{
    
    	@Override
    	public List<StudentInfo> select(StudentInfo si) {
    		// TODO Auto-generated method stub
    		String sql = "select * from studentInfo where 1=1";
    		List<StudentInfo> list = new ArrayList<StudentInfo>();
    		List<Object> olist = new ArrayList<Object>();
    		if(si.getsId()!=null) {
    			sql += " and sid=?";
    			olist.add(si.getsId());
    		}
    		try {
    			ResultSet rs = this.executeQuery(sql, olist);
    			while(rs.next()) {
    				StudentInfo sis = new StudentInfo();
    				sis.setsId(rs.getInt("sid"));
    				sis.setsName(rs.getString("sname"));
    				sis.setsGender(rs.getString("sgender"));
    				sis.setsAge(rs.getInt("sage"));
    				sis.setsAddress(rs.getString("saddress"));
    				sis.setsEmail(rs.getString("semail"));
    				list.add(sis);
    			}
    		} catch (SQLException e) {
    			// TODO Auto-generated catch block
    			e.printStackTrace();
    		}finally {
    			this.closeAll();
    		}
    		return list;
    	}
    
    	@Override
    	public int update(StudentInfo si) {
    		// TODO Auto-generated method stub
    		String sql = "update studentInfo set sname=?,sgender=?,sage=?,saddress=?,semail=? where sid=?";
    		return this.executeUpdate(sql, si.getsName(),si.getsGender(),si.getsAge(),si.getsAddress(),si.getsEmail(),si.getsId());
    	}
    
    	@Override
    	public int delete(StudentInfo si) {
    		// TODO Auto-generated method stub
    		String sql = "delete from studentInfo where sid=?";
    		return this.executeUpdate(sql, si.getsId());
    	}
    
    }

Service层：

package com.accp.service;
    
    import java.util.List;
    
    import com.accp.entity.StudentInfo;
    
    public interface StudentInfoService {
    	public List<StudentInfo> select(StudentInfo si);
    	
    	public int update(StudentInfo si);
    	
    	public int delete(StudentInfo si);
    }

Service层Impl实现类：

package com.accp.service.impl;
    
    import java.util.List;
    
    import com.accp.dao.StudentInfoDao;
    import com.accp.dao.impl.StudentInfoDaoImpl;
    import com.accp.entity.StudentInfo;
    import com.accp.service.StudentInfoService;
    
    public class StudentInfoServiceImpl implements StudentInfoService{
    	
    	StudentInfoDao sid = new StudentInfoDaoImpl();
    	@Override
    	public List<StudentInfo> select(StudentInfo si) {
    		// TODO Auto-generated method stub
    		return sid.select(si);
    	}
    
    	@Override
    	public int update(StudentInfo si) {
    		// TODO Auto-generated method stub
    		return sid.update(si);
    	}
    
    	@Override
    	public int delete(StudentInfo si) {
    		// TODO Auto-generated method stub
    		return sid.delete(si);
    	}
    
    }

Servlet层删除：

package com.accp.servlet;
    
    import java.io.IOException;
    import java.io.PrintWriter;
    
    import javax.servlet.ServletException;
    import javax.servlet.annotation.WebServlet;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    import com.accp.dao.impl.StudentInfoDaoImpl;
    import com.accp.entity.StudentInfo;
    
    /**
     * Servlet implementation class DeleteStudentInfoServlet
     */
    @WebServlet("/dsis")
    public class DeleteStudentInfoServlet extends HttpServlet {
    	private static final long serialVersionUID = 1L;
           
        /**
         * @see HttpServlet#HttpServlet()
         */
        public DeleteStudentInfoServlet() {
            super();
            // TODO Auto-generated constructor stub
        }
    
    	/**
    	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
    	 */
    	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		// TODO Auto-generated method stub
    		request.setCharacterEncoding("UTF-8");
    		response.setCharacterEncoding("UTF-8");
    		response.setContentType("text/html; charset=UTF-8");
    		String id = request.getParameter("id"); //获得要删除的用户ID
    		StudentInfo si = new StudentInfo();
    		si.setsId(Integer.valueOf(id));
    		StudentInfoDaoImpl sis = new StudentInfoDaoImpl();
    		int count = sis.delete(si);	//调用删除方法
    		
    		//写入流
    		PrintWriter out = response.getWriter();
    		out.print(count);
    		out.flush();
    		out.close();
    	}
    
    	/**
    	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
    	 */
    	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		// TODO Auto-generated method stub
    		doGet(request, response);
    	}
    
    }

Servlet层修改：

package com.accp.servlet;
    
    import java.io.IOException;
    import javax.servlet.ServletException;
    import javax.servlet.annotation.WebServlet;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    import com.accp.dao.impl.StudentInfoDaoImpl;
    import com.accp.entity.StudentInfo;
    
    /**
     * Servlet implementation class UpdateStudentInfoServlet
     */
    @WebServlet("/usis")
    public class UpdateStudentInfoServlet extends HttpServlet {
    	private static final long serialVersionUID = 1L;
    
    	/**
    	 * @see HttpServlet#HttpServlet()
    	 */
    	public UpdateStudentInfoServlet() {
    		super();
    		// TODO Auto-generated constructor stub
    	}
    
    	/**
    	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse
    	 *      response)
    	 */
    	protected void doGet(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
    		// TODO Auto-generated method stub
    		request.setCharacterEncoding("UTF-8");
    		response.setCharacterEncoding("UTF-8");
    		response.setContentType("text/html; charset=UTF-8");
    
    		/*
    		 * 获得修改后的学员信息
    		 */
    		String id = request.getParameter("id");
    		String name = request.getParameter("name");
    		name = new String(name.getBytes("ISO-8859-1"), "UTF-8");
    		String gender = request.getParameter("gender");
    		gender = new String(gender.getBytes("ISO-8859-1"), "UTF-8");
    		String age = request.getParameter("age");
    		String address = request.getParameter("address");
    		address = new String(address.getBytes("ISO-8859-1"), "UTF-8");
    		String email = request.getParameter("email");
    
    		// 申明学员对象存入值
    		StudentInfo si = new StudentInfo();
    		si.setsId(Integer.valueOf(id));
    		si.setsName(name);
    		si.setsGender(gender);
    		si.setsAge(Integer.valueOf(age));
    		si.setsAddress(address);
    		si.setsEmail(email);
    		StudentInfoDaoImpl sis = new StudentInfoDaoImpl();
    
    		// 调用修改方法
    		int count = sis.update(si);
    
    		// 修改后提示
    		if (count > 0) {
    			response.getWriter().write("<script>alert('修改成功！');window.location.href='ssis'</script>");
    		} else {
    			response.getWriter().write("<script>alert('修改失败！');history.go(-1)</script>");
    		}
    	}
    
    	/**
    	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse
    	 *      response)
    	 */
    	protected void doPost(HttpServletRequest request, HttpServletResponse response)
    			throws ServletException, IOException {
    		// TODO Auto-generated method stub
    		doGet(request, response);
    	}
    
    }

Servlet层查询：

package com.accp.servlet;
    
    import java.io.IOException;
    import java.util.List;
    
    import javax.servlet.ServletException;
    import javax.servlet.annotation.WebServlet;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    import com.accp.dao.impl.StudentInfoDaoImpl;
    import com.accp.entity.StudentInfo;
    
    /**
     * Servlet implementation class SelectStudentInfoServlet
     */
    @WebServlet("/ssis")
    public class SelectStudentInfoServlet extends HttpServlet {
    	private static final long serialVersionUID = 1L;
           
        /**
         * @see HttpServlet#HttpServlet()
         */
        public SelectStudentInfoServlet() {
            super();
            // TODO Auto-generated constructor stub
        }
    
    	/**
    	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
    	 */
    	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		// TODO Auto-generated method stub
    		request.setCharacterEncoding("UTF-8");
    		response.setCharacterEncoding("UTF-8");
    		response.setContentType("text/html; charset=UTF-8");
    		StudentInfo si = new StudentInfo();
    		StudentInfoDaoImpl sis = new StudentInfoDaoImpl();
    		List<StudentInfo> list = sis.select(si);	//调用查询方法
    		request.setAttribute("list",list);	//存入作用域
    		
    		//转发
    		request.getRequestDispatcher("index.jsp").forward(request, response);
    	}
    
    	/**
    	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
    	 */
    	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		// TODO Auto-generated method stub
    		doGet(request, response);
    	}
    
    }

Servlet层传值到修改页面查看：

package com.accp.servlet;
    
    import java.io.IOException;
    import java.util.List;
    
    import javax.servlet.ServletException;
    import javax.servlet.annotation.WebServlet;
    import javax.servlet.http.HttpServlet;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    
    import com.accp.dao.impl.StudentInfoDaoImpl;
    import com.accp.entity.StudentInfo;
    
    /**
     * Servlet implementation class SelectStudentInfoByIdServlet
     */
    @WebServlet("/ssibis")
    public class SelectStudentInfoByIdServlet extends HttpServlet {
    	private static final long serialVersionUID = 1L;
           
        /**
         * @see HttpServlet#HttpServlet()
         */
        public SelectStudentInfoByIdServlet() {
            super();
            // TODO Auto-generated constructor stub
        }
    
    	/**
    	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
    	 */
    	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		// TODO Auto-generated method stub
    		request.setCharacterEncoding("UTF-8");
    		response.setCharacterEncoding("UTF-8");
    		response.setContentType("text/html; charset=UTF-8");
    		String id = request.getParameter("id");	//获得要修改的学员ID
    		StudentInfo si = new StudentInfo();
    		si.setsId(Integer.valueOf(id));
    		StudentInfoDaoImpl sis = new StudentInfoDaoImpl();
    		List<StudentInfo> list = sis.select(si);	//通过ID去查询该学员信息
    		request.setAttribute("info", list.get(0));	//将信息存入作用域
    		
    		//转发
    		request.getRequestDispatcher("upd.jsp").forward(request, response);
    		
    	}
    
    	/**
    	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
    	 */
    	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    		// TODO Auto-generated method stub
    		doGet(request, response);
    	}
    
    }

显示页面代码：

<%@ page language="java" contentType="text/html; charset=UTF-8"
    	pageEncoding="UTF-8"%>
    <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Insert title here</title>
    <script type="text/javascript" src="js/jquery-1.12.4.js"></script>
    <script type="text/javascript">
    	//删除方法
    	function del(id) {
    		if (confirm("确认要删除该学员信息？")) { //确认是否删除
    
    			//调用ajax方法
    			$.ajax({
    				url : "dsis",
    				type : "get",
    				data : "id=" + id,
    				success : function(data) {
    					if (data > 0) {
    						alert("删除成功！");
    						window.location.href = "ssis";
    					} else {
    						alert("删除失败！");
    					}
    				}
    			})
    		}
    	}
    </script>
    <style type="text/css">
    table tr:nth-of-type(even) {
    	background: #ccc;
    }
    </style>
    </head>
    <body>
    	<table align="center" border="1">
    		<tr align="center">
    			<td colspan="7" style="font-weight: bold;">学员信息列表</td>
    		</tr>
    		<tr align="center">
    			<td>学员编号</td>
    			<td>学员姓名</td>
    			<td>学员性别</td>
    			<td>学员年龄</td>
    			<td>家庭住址</td>
    			<td>Email</td>
    			<td>操作</td>
    		</tr>
    		<c:forEach items="${requestScope.list}" var="item">
    			<tr align="center">
    				<td>${item.sId}</td>
    				<td><a href="ssibis?id=${item.sId }">${item.sName}</a></td>
    				<td>${item.sGender}</td>
    				<td>${item.sAge}</td>
    				<td>${item.sAddress}</td>
    				<td>${item.sEmail}</td>
    				<td><a href="javascript:del(${item.sId})">删除</a></td>
    			</tr>
    		</c:forEach>
    	</table>
    </body>
    </html>

<%@ page language="java" contentType="text/html; charset=UTF-8"
        pageEncoding="UTF-8"%>
    <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
    <html>
    <head>
    <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
    <title>Insert title here</title>
    <script type="text/javascript" src="js/jquery-1.12.4.js"></script>
    <script type="text/javascript">
    
    	//验证非空方法
    	function check(){
    		var name = $("#name").val();
    		var sex = $("#gender").val();
    		var age = $("#age").val();
    		var address = $("#address").val();
    		var email = $("#email").val();
    		if(name.trim().length==0){
    			alert("姓名不能为空");
    			return false;
    		}
    		if(sex.trim().length==0){
    			alert("性别不能为空");
    			return false;
    		}
    		if(age.trim().length==0){
    			alert("年龄不能为空");
    			return false;
    		}		
    		return true;
    	}
    </script>
    </head>
    <body>
    	<form action="usis"  method="get">
    		<table border="1" align="center">
    			<tr align="center">
    				<td colspan="2"><h2>学员信息</h2></td>
    			</tr>
    			<tr align="center">
    				<td>学员姓名</td>
    				<td><input id="name" name="name" type="text" value="${requestScope.info.sName }"/></td>
    			</tr>
    			<tr align="center">
    				<td>学员性别</td>
    				<td><input id="gender" name="gender" type="text" value="${requestScope.info.sGender }"/></td>
    			</tr>
    			<tr>
    				<td>学员年龄</td>
    				<td><input id="age" name="age" type="text" value="${requestScope.info.sAge }"/></td>
    			</tr>
    			<tr align="center">
    				<td>家庭住址</td>
    				<td><input id="address" name="address" type="text" value="${requestScope.info.sAddress }"/></td>
    			</tr>
    			<tr align="center">
    				<td>Email</td>
    				<td><input id="email" name="email" type="text" value="${requestScope.info.sEmail }"/></td>
    			</tr>
    			<tr align="center">
     				<td colspan="2">
     				
     				
    				
    				<input name="id" type="hidden" value="${requestScope.info.sId }"/>
    				<input type="submit" value="修改" onclick="return check()"/></td>
    			</tr>
    		</table>
    	</form>
    </body>
    </html>

[20190105100308722.jpg]: /images/20220330/4e8e1bb088014bc59d783f698d9679d1.png