通用分页+jsp增删改查

①准备工作

1.1打开navicat进行数据库连接

1.2进行数据库连接

（要注意这里连接，我的安装mysql的时候是没有密码的)

1.3新建一个数据库

1.4然后将表格导入

（这里我是导入的数据，你们可以自己建表进行数据添加）

1.5在数据库新建查询

将要用到的增加，修改，删除，查询语句提前写好(这里的删除的语句跟sql和oracle的代码不一样了要加上一个from)

②打开eclipse开始建项目

（主要要建的是web的动态项目 Dynamic Web Project）

2.1项目创建

要注意下一步最后的这个要勾选上

2.2先导入需要用到的jar包

（注意jar包的位置要放在WEB-INF的lib下面）

2.3然后开始建包建类

(我这里是分包建类 action指的是处理请求的处理层 dao指的是对数据库进行增删改查的方法类 entity指的是实体类 用来存放数据 uitl指的是数据库连接类)

③开始书写代码

3.1数据库连接类

这里是直接调用的连接类

import java.io.InputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Properties;

/**
 * 提供了一组获得或关闭数据库对象的方法
 * 
 */
public class DBAccess {
	private static String driver;
	private static String url;
	private static String user;
	private static String password;

	static {// 静态块执行一次，加载 驱动一次
		try {
			InputStream is = DBAccess.class
					.getResourceAsStream("config.properties");

			Properties properties = new Properties();
			properties.load(is);

			driver = properties.getProperty("driver");
			url = properties.getProperty("url");
			user = properties.getProperty("user");
			password = properties.getProperty("pwd");

			Class.forName(driver);
		} catch (Exception e) {
			e.printStackTrace();
			throw new RuntimeException(e);
		}
	}

	/**
	 * 获得数据连接对象
	 * 
	 * @return
	 */
	public static Connection getConnection() {
		try {
			Connection conn = DriverManager.getConnection(url, user, password);
			return conn;
		} catch (SQLException e) {
			e.printStackTrace();
			throw new RuntimeException(e);
		}
	}

	public static void close(ResultSet rs) {
		if (null != rs) {
			try {
				rs.close();
			} catch (SQLException e) {
				e.printStackTrace();
				throw new RuntimeException(e);
			}
		}
	}

	public static void close(Statement stmt) {
		if (null != stmt) {
			try {
				stmt.close();
			} catch (SQLException e) {
				e.printStackTrace();
				throw new RuntimeException(e);
			}
		}
	}

	public static void close(Connection conn) {
		if (null != conn) {
			try {
				conn.close();
			} catch (SQLException e) {
				e.printStackTrace();
				throw new RuntimeException(e);
			}
		}
	}

	public static void close(Connection conn, Statement stmt, ResultSet rs) {
		close(rs);
		close(stmt);
		close(conn);
	}

	public static boolean isOracle() {
		return "oracle.jdbc.driver.OracleDriver".equals(driver);
	}

	public static boolean isSQLServer() {
		return "com.microsoft.sqlserver.jdbc.SQLServerDriver".equals(driver);
	}
	
	public static boolean isMysql() {
		return "com.mysql.jdbc.Driver".equals(driver);
	}

	public static void main(String[] args) {
		Connection conn = DBAccess.getConnection();
		DBAccess.close(conn);
		System.out.println("isOracle：" + isOracle());
		System.out.println("isSQLServer：" + isSQLServer());
		System.out.println("isMysql：" + isMysql());
		System.out.println("数据库连接(关闭)成功");
	}
}

注意url是否与主机数据库名一致 ,user跟pwd是否正确 (我安装mysql的时候没有设置密码所以直接为空)

#mysql
driver=com.mysql.jdbc.Driver
url=jdbc:mysql://localhost:3306/tanle?useUnicode=true&characterEncoding=UTF-8
user=root
pwd=

3.2实体类

实体类数据类型要与数据库一致，属性名最好一致(我的数据库字段仅供参考)

仅供参考，具体与自身的为主(实体类主要用来实例化存取数据 有set和get方法 还有两个构造方法 一个无参一个有参)

import java.io.Serializable;
public class Student implements Serializable{
	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;
	private String id;
	private String job;
	private String company;
	private String address;
	private String salary;
	private String url;
	private String limit;
	private String time;
	private String desc;
	private String jobHandle;
	private String addressHandle;
	public String getId() {
		return id;
	}
	public void setId(String id) {
		this.id = id;
	}
	public String getJob() {
		return job;
	}
	public void setJob(String job) {
		this.job = job;
	}
	public String getCompany() {
		return company;
	}
	public void setCompany(String company) {
		this.company = company;
	}
	public String getAddress() {
		return address;
	}
	public void setAddress(String address) {
		this.address = address;
	}
	public String getSalary() {
		return salary;
	}
	public void setSalary(String salary) {
		this.salary = salary;
	}
	public String getUrl() {
		return url;
	}
	public void setUrl(String url) {
		this.url = url;
	}
	public String getLimit() {
		return limit;
	}
	public void setLimit(String limit) {
		this.limit = limit;
	}
	public String getTime() {
		return time;
	}
	public void setTime(String time) {
		this.time = time;
	}
	public String getDesc() {
		return desc;
	}
	public void setDesc(String desc) {
		this.desc = desc;
	}
	public String getJobHandle() {
		return jobHandle;
	}
	public void setJobHandle(String jobHandle) {
		this.jobHandle = jobHandle;
	}
	public String getAddressHandle() {
		return addressHandle;
	}
	public void setAddressHandle(String addressHandle) {
		this.addressHandle = addressHandle;
	}
	
	public Student() {

	}
	public Student(String id, String job, String company, String address, String salary, String url, String limit,
			String time, String desc, String jobHandle, String addressHandle) {
		this.id = id;
		this.job = job;
		this.company = company;
		this.address = address;
		this.salary = salary;
		this.url = url;
		this.limit = limit;
		this.time = time;
		this.desc = desc;
		this.jobHandle = jobHandle;
		this.addressHandle = addressHandle;
	}
	
	
	
}

3.3dao类

连接数据库操作类对数据库的数据进行增加删除修改

	//模糊查询
	public List<Student> list(String sname,PageBean pageBean){
		List<Student> list=new ArrayList<Student>();
		//模糊查询的条件
		String sql="select * from t_solr_job";
		if(sname!=null) {
			sql="select * from t_solr_job where company like '%"+sname+"%'";
		}
		return this.query(sql, pageBean, new Callback<Student>() {
			
			@Override
			public List<Student> foreach(ResultSet rs) throws SQLException {
				// TODO Auto-generated method stub
				Student stu=null;
				while(rs.next()) {
					stu=new Student();
					stu.setId(rs.getString("id"));
					stu.setJob(rs.getString("job"));
					stu.setCompany(rs.getString("company"));
					stu.setAddress(rs.getString("address"));
					stu.setSalary(rs.getString("salary"));
					stu.setUrl(rs.getString("url"));
					stu.setLimit(rs.getString("limito"));
					stu.setTime(rs.getString("time"));
					stu.setDesc(rs.getString("descc"));
					stu.setJobHandle(rs.getString("jobHandle"));
					stu.setAddressHandle(rs.getString("addressHandle"));
					list.add(stu);
				}
				return list;
			}
		});
	} 
	
	public int delete(String id){
		int n=0;
		Connection	con=null;
		PreparedStatement ps=null;
		try {
			con=DBAccess.getConnection();
			String sql="delete from t_solr_job where id="+id;
			ps=con.prepareStatement(sql);
			n=ps.executeUpdate();
		} catch (Exception e) {
			// TODO: handle exception
			e.printStackTrace();
		}finally {
			DBAccess.close(con, ps, null);
		}
		return n;
	}
	//单个查询
	public List<Student> list(String id){
		List<Student> ls=new ArrayList<Student>();
		Connection	con=null;
		PreparedStatement ps=null;
		ResultSet rs=null;
		try {
			con=DBAccess.getConnection();
			String sql="select * from t_solr_job where id="+id;
			ps=con.prepareStatement(sql);
			rs=ps.executeQuery();
			if(rs.next()) {
				Student stu=new Student();
				stu.setId(rs.getString("id"));
				stu.setJob(rs.getString("job"));
				stu.setCompany(rs.getString("company"));
				stu.setAddress(rs.getString("address"));
				stu.setSalary(rs.getString("salary"));
				stu.setUrl(rs.getString("url"));
				stu.setLimit(rs.getString("limito"));
				stu.setTime(rs.getString("time"));
				stu.setDesc(rs.getString("descc"));
				stu.setJobHandle(rs.getString("jobHandle"));
				stu.setAddressHandle(rs.getString("addressHandle"));
				ls.add(stu);
			}
		} catch (Exception e) {
			// TODO: handle exception
			e.printStackTrace();
		}finally {
			DBAccess.close(con, ps, rs);
		}
		return ls;
	}
	//修改
	public int update(String id,Student stu){
		int n=0;
		Connection	con=null;
		PreparedStatement ps=null;
		try {
			con=DBAccess.getConnection();
			String sql="update t_solr_job set job=?,company=?,address=?,salary=?,url=?,limito=? where id="+id;
			ps=con.prepareStatement(sql);
			ps.setString(1, stu.getJob());
			ps.setString(2, stu.getCompany());
			ps.setString(3, stu.getAddress());
			ps.setString(4, stu.getSalary());
			ps.setString(5, stu.getUrl());
			ps.setString(6, stu.getLimit());
			n=ps.executeUpdate();
		} catch (Exception e) {
			// TODO: handle exception
			e.printStackTrace();
		}finally {
			DBAccess.close(con, ps, null);
		}
		return n;
	}
	//增加
	public int insert(Student stu){
		int n=0;
		Connection	con=null;
		PreparedStatement ps=null;
		try {
			con=DBAccess.getConnection();
			String sql="insert into t_solr_job(id,job,company,address,salary,url,limito,time,descc,jobHandle,addressHandle)values(?,?,?,?,?,?,?,?,?,?,?)";
			ps=con.prepareStatement(sql);
			ps.setString(1, stu.getId());
			ps.setString(2, stu.getJob());
			ps.setString(3, stu.getCompany());
			ps.setString(4, stu.getAddress());
			ps.setString(5, stu.getSalary());
			ps.setString(6, stu.getUrl());
			ps.setString(7, stu.getLimit());
			ps.setString(8, stu.getTime());
			ps.setString(9, stu.getDesc());
			ps.setString(10, stu.getJobHandle());
			ps.setString(11, stu.getAddressHandle());
			n=ps.executeUpdate();
		} catch (Exception e) {
			// TODO: handle exception
			e.printStackTrace();
		}finally {
			DBAccess.close(con, ps, null);
		}
		return n;
	}

我这里写了分页(pagebean)

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.List;
public class BaseDao<E> {
	public List<E> query(String sql,PageBean pageBean,Callback<E> callback){
		List<E> ls=new ArrayList<E>();
		Connection con=null;
		PreparedStatement ps=null;
		ResultSet rs=null;
		//第一次查询 查总记录数
		if(null!=pageBean&&pageBean.isPagination()) {
			try {
				con=DBAccess.getConnection();
				String countsql=this.getCountSql(sql);
				ps=con.prepareStatement(countsql);
				rs=ps.executeQuery();
				if(rs.next()) {
					pageBean.setTotal(rs.getInt(1));
				}
			} catch (SQLException e) {
				// TODO: handle exception
				throw new RuntimeException();
			}finally {
				DBAccess.close(null, ps, rs);
			}
			
		}
		//第二次查询 查询满足条件的记录数
		if(null!=pageBean&&pageBean.isPagination()) {
			sql=this.getPageSql(sql, pageBean);
		}
		try {
			con=DBAccess.getConnection();
			ps=con.prepareStatement(sql);
			rs=ps.executeQuery();
			return callback.foreach(rs);
		} catch (SQLException e) {
			// TODO: handle exception
			throw new RuntimeException();
		}finally {
			DBAccess.close(null, ps, rs);
		}
	}
	
	/**
	 * 把普通sql转成查总记录数sql
	 * @param sql
	 * @return
	 */
	public String getCountSql(String sql) {
		String countSql="select count(*) from ("+sql+") t";
		return countSql;
	}
	/**
	 * 查满足分页的sql
	 * @param sql
	 * @return
	 */
	public String getPageSql(String sql,PageBean pageBean) {
		String pageSql=sql+" limit "+pageBean.getStartIndex()+","+pageBean.getRows()+"";
		return pageSql;
	}
}

3.4action请求处理

这里我写了6个Servlect

StudentServlet查询所有的赋值到界面

import java.io.IOException;
import java.util.Arrays;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Set;

import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
/**
 * Servlet implementation class StudentServlet
 */
@WebServlet("/StudentServlet")
public class StudentServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
	StudentDao studentDao=new StudentDao();
	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doPost(request, response);
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		request.setCharacterEncoding("utf-8");
		response.setContentType("text/html; charset=UTF-8");
		/*//获取项目名
		String contextPath = request.getContextPath();
		//获取请求路径
		String servletPath = request.getServletPath();*/
		
		//Student stu=new Student();
		//根据参数名获取一组参数
		String name=request.getParameter("name");
//		String[] likes = request.getParameterValues("likes");
		
		//获取请求的所有数据
		/*Map<String, String[]> parameterMap=request.getParameterMap();
		Set<Entry<String, String[]>> entrySet = parameterMap.entrySet();
		for(Entry<String, String[]> entry:entrySet) {
			System.out.println(entry.getKey());
			System.out.println(Arrays.toString(entry.getValue()));

		}*/
		if("".equals(name)) {
			name=null;
		}
		
		PageBean pageBean=new PageBean();
		pageBean.initPageBean(request, pageBean);
		List<Student> list = studentDao.list(name, pageBean);
		request.setAttribute("list", list);
		
		request.setAttribute("pageBean", pageBean);
		request.getRequestDispatcher("index.jsp").forward(request, response);
	}

}

StudentServletDelete删除数据

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;
/**
 * Servlet implementation class StudentServletDelete
 */
@WebServlet("/StudentServletDelete")
public class StudentServletDelete extends HttpServlet {
	private static final long serialVersionUID = 1L;
	StudentDao studentDao=new StudentDao();   
    /**
     * @see HttpServlet#HttpServlet()
     */
    public StudentServletDelete() {
        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
		doPost(request, response);
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		request.setCharacterEncoding("utf-8");
		response.setContentType("text/html; charset=UTF-8");
		String id = request.getParameter("id");
		PageBean pageBean=new PageBean();
		pageBean.initPageBean(request, pageBean);
		int n = studentDao.delete(id);
		if(n<0) {
			response.getWriter().print("<script>alert('删除失败');location.href='StudentServlet';</script>");
		}else {
			response.getWriter().print("<script>alert('删除成功');location.href='StudentServlet';</script>");
		}
	}

}

StudentServletInsert新增数据

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;
/**
 * Servlet implementation class StudentServletInsert
 */
@WebServlet("/StudentServletInsert")
public class StudentServletInsert extends HttpServlet {
	private static final long serialVersionUID = 1L;
	
	StudentDao studentDao=new StudentDao();
	/**
	 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		doPost(request, response);
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		request.setCharacterEncoding("utf-8");
		response.setContentType("text/html; charset=UTF-8");
		String id=request.getParameter("id");
		String job=request.getParameter("job");
		String company=request.getParameter("company");
		String address=request.getParameter("address");
		String salary=request.getParameter("salary");
		String url=request.getParameter("url");
		String limito=request.getParameter("limito");
		String time=request.getParameter("time");
		String descc=request.getParameter("descc");
		String jobHandle=request.getParameter("jobhandle");
		String addressHandle=request.getParameter("addresshandel");
		
		Student stu=new Student(id, job, company, address, salary, url, limito, time, descc, jobHandle, addressHandle);
		int n = studentDao.insert(stu);
		if(n<0) {
			response.getWriter().print("<script>alert('增加失败');location.href='StudentServlet';</script>");
		}else {
			response.getWriter().print("<script>alert('增加成功');location.href='StudentServlet';</script>");
		}
	}

}

StudentServletUpcx修改之前的查询赋值

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;

/**
 * Servlet implementation class StudentServletUpcx
 */
@WebServlet("/StudentServletUpcx")
public class StudentServletUpcx extends HttpServlet {
	private static final long serialVersionUID = 1L;
	StudentDao studentDao=new StudentDao();   
    /**
     * @see HttpServlet#HttpServlet()
     */
    public StudentServletUpcx() {
        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
		doPost(request, response);
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		String id=request.getParameter("id");
		List<Student> list = studentDao.list(id);
		request.setAttribute("list", list);
		request.getRequestDispatcher("update.jsp").forward(request, response);
	}

}

StudentServletUpdate修改

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;

/**
 * Servlet implementation class StudentServletUpdate
 */
@WebServlet("/StudentServletUpdate")
public class StudentServletUpdate extends HttpServlet {
	private static final long serialVersionUID = 1L;
       StudentDao studentDao=new StudentDao();
    /**
     * @see HttpServlet#HttpServlet()
     */
    public StudentServletUpdate() {
        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
		doPost(request, response);
	}

	/**
	 * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
	 */
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		// TODO Auto-generated method stub
		request.setCharacterEncoding("utf-8");
		response.setContentType("text/html; charset=UTF-8");
		
		String id=request.getParameter("id");
		String job=request.getParameter("job");
		String company=request.getParameter("company");
		String address=request.getParameter("address");
		String salary=request.getParameter("salary");
		String url=request.getParameter("url");
		String limito=request.getParameter("limito");
		Student stu=new Student(id, job, company, address, salary, url, limito, null, null, null, null);
		int n = studentDao.update(id, stu);
		if(n<0) {
			response.getWriter().print("<script>alert('修改失败');location.href='StudentServlet';</script>");
		}else {
			response.getWriter().print("<script>alert('修改成功');location.href='StudentServlet';</script>");
		}
	
	}

}

3.5界面赋值

主界面(数据显示界面)

<%@ 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>
</head>
<body>
	<c:if test="${empty list }">
		<jsp:forward page="StudentServlet"></jsp:forward>
	</c:if>
	<form action="StudentServlet" method="post">
		公司名称：<input type="text" name="name"/>
		<input type="submit" value-"查询"/>
	</form>
	<table border="2px" style="width: 99%">
			<tr>
				<td>编号</td>
				<td>类型</td>
				<td>公司名称</td>
				<td>公司地址</td>
				<td>工资</td>
				<td>网址</td>
				<td>学历要求</td>
				<td>时间</td>
				<td>操作</td>
			</tr>
		<c:forEach items="${list }" var="i">
			<tr>
				<td>${i.id }</td>
				<td>${i.job }</td>
				<td>${i.company }</td>
				<td>${i.address }</td>
				<td>${i.salary }</td>
				<td>${i.url }</td>
				<td>${i.limit }</td>
				<td>${i.time }</td>
				<td>
				<a href="StudentServletDelete?id=${i.id }" onclick="return confirm('您确定要删除吗？')">删除</a>
				<a href="StudentServletUpcx?id=${i.id }">修改</a>
				<a href="StudentServletDetails?id=${i.id }">查看详情</a>
				</td>
			</tr>
		</c:forEach>
	</table>
	当前第${pageBean.page }页  共${pageBean.maxPage }页 共${pageBean.total }
	<a href='javascript:doForward(1)'>首页</a>
	<a href='javascript:doForward("${pageBean.frontPage }")'>上一页</a>
	<a href='javascript:doForward("${pageBean.nextPage }")'>下一页<a>
	<a href='javascript:doForward("${pageBean.maxPage }")'>尾页<a>
	<form id="form" action="${pageBean.url }"  method="post">
		<input type="text" name="page" id="page"/>
	
	</form>
	<script type="text/javascript">
		function doForward(page){
			console.log(page);
			document.getElementById("page").value=page;
			document.getElementById("form").submit();
		}
	</script>
<br/>
<button><a href="add.jsp">增加</a></button>
</body>
</html>

数据显示结果

④总结

写代码之前要理清自己的思路，按照自己的步骤一步一步来，就会很清晰。写一片区域运行测试一下。要细心不能太粗心。
谢谢观看昂!