第83节:Java中的学生管理系统分页功能

分页功能一般可以做成两种，一种是物理分页，另一种是逻辑分页。这两种功能是有各自的特点的，物理分页是查询的时候，对数据库进行访问，只是查一页数据就进行返回，其特点是对内存中数据量存储不大，只是缺点就是要对数据库不断的进行访问；而对逻辑分页来说，就有所不同，它是一下子就把所有的数据全部查询出来，然后放入到内存中，访问速度快，缺点就是对内存空间不足，数据量过大。

select * from stu limit 5;复制代码

// offset 偏移前面的多少条，offset 1 跳过前面的一条select * from stu limit 5 offset 5;复制代码

SELECT * FROM stu LIMIT 5 , 5;复制代码

SELECT * FROM stu LIMIT 5 , 2;复制代码

SELECT * FROM stu LIMIT 2 , 5;复制代码

写分页的dao模式

// index.jsp
分页显示所有学生
复制代码

// StudentListPageServlet//1. 获取需要显示的页码数int currentPage =Integer.parseInt( request.getParameter("currentPage"));复制代码

// StudentDao// 接口中定义的成员都是常量// 一页显示多少条记录int PAGE_SIZE = 5;// 分页dao,查询当页的学生数据List
    
      findStudentByPage(int currentPage) throws SQLException;复制代码
    

// StudentDaoImpl	@Override	public List
    
      findStudentByPage(int currentPage) throws SQLException {		// TODO Auto-generated method stub		QueryRunner runner = new QueryRunner(JDBCUtil02.getDataSource());		// 第一个问号，一页返回多少条记录，第二个问号，跳过前面的多少条记录		//5 0 --- 第一页 (1-1)*5		//5 5  --- 第二页 (2-1)*5		//5 10  --- 第三页		return runner.query("select * from stu limit ? offset ?", new BeanListHandler
     
      (Student.class),PAGE_SIZE , (currentPage-1)*PAGE_SIZE);			}复制代码
     
    

业务逻辑

select count(*) from stu;复制代码

业务逻辑

package com.dashucoding.servlet;import java.io.IOException;import java.sql.SQLException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.dashucoding.domain.PageBean;import com.dashucoding.service.StudentService;import com.dashucoding.service.impl.StudentServiceImpl;/** * 这是用于分页显示学生列表的servlet */public class StudentListPageServlet extends HttpServlet {		protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {		try {			//1. 获取需要显示的页码数			int currentPage =Integer.parseInt( request.getParameter("currentPage"));						//2. 根据指定的页数，去获取该页的数据回来			//List
    
      --- list.jsp						StudentService service = new StudentServiceImpl();			PageBean pageBean= service.findStudentByPage(currentPage);			request.setAttribute("pageBean", pageBean);			//3. 跳转界面。			request.getRequestDispatcher("list_page.jsp").forward(request, response);		} catch (SQLException e) {			e.printStackTrace();		}	}		protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {		// TODO Auto-generated method stub		doGet(request, response);	}	}复制代码
    

去业务逻辑去找

package com.dashucoding.service;import java.sql.SQLException;import java.util.List;import com.dashucoding.domain.PageBean;import com.dashucoding.domain.Student;/* * 这是学生的业务处理规范 * */public interface StudentService {	// 分页dao,查询当页的学生数据	// 分页的很多小逻辑业务 可以做到service里面	// 业务做到service里面，做的就是bean了，当前页，总页数，显示条数， 总记录数	// 返回的是一个bean了	// 返回的是PageBean里面的所有数据了	PageBean findStudentByPage(int currentPage) throws SQLException;	// 根据姓名或性别，查询	List
    
      searchStudent(String sname, String sgender) throws SQLException;	/*	 * 查询所有学生 list
     
      	 */	List
      
        findAll() throws SQLException;	void insert(Student student) throws SQLException;	// sid根据id删除学生	void delete(int sid) throws SQLException;	// 根据id查询单个学生对象	Student findStudentById(int sid) throws SQLException;	// 更新学生信息	void update(Student student) throws SQLException;}复制代码
      
     
    

package com.dashucoding.service.impl;import java.sql.SQLException;import java.util.List;import com.dashucoding.dao.StudentDao;import com.dashucoding.dao.impl.StudentDaoImpl;import com.dashucoding.domain.PageBean;import com.dashucoding.domain.Student;import com.dashucoding.service.StudentService;/* * 这是学生业务实现 * */public class StudentServiceImpl implements StudentService {	@Override	public List
    
      findAll() throws SQLException {		StudentDao dao = new StudentDaoImpl();		return dao.findAll();	}	@Override	public void insert(Student student) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		dao.insert(student);	}	@Override	public void delete(int sid) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		dao.delete(sid);	}	@Override	public Student findStudentById(int sid) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		return dao.findStudentById(sid);	}	@Override	public void update(Student student) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		dao.update(student);	}	@Override	public List
     
       searchStudent(String sname, String sgender) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		return dao.searchStudent(sname, sgender);	}	@Override	public PageBean findStudentByPage(int currentPage) throws SQLException {		// TODO Auto-generated method stub		// 封装分页的该页的数据		PageBean
      
        pageBean = new PageBean
       
        ();				int pageSize = StudentDao.PAGE_SIZE;				// 设置当前页		pageBean.setCurrentPage(currentPage);		// 每条记录		pageBean.setPageSize(pageSize);				StudentDao dao = new StudentDaoImpl();		List
        
          list = dao.findStudentByPage(currentPage);		pageBean.setList(list);		// 总记录数，总页数		int count = dao.findCount();		pageBean.setTotalSize(count);				// 总页数		pageBean.setTotalPage(count % pageSize == 0 ? count / pageSize : (count / pageSize) + 1);				return null;	}}复制代码
        
       
      
     
    

// 封装的数据package com.dashucoding.domain;import java.util.List;// 一个用于封装了分页的数据// 有： 当前学生集合数据，总的记录数，总的页数，当前页，每页的显示记录数public class PageBean
    
      {	private int currentPage; // 当前页	private int totalPage;// 总页数	private int pageSize;// 每页的记录数，每页要显示多少记录	private int totalSize; // 总的记录数	private List
     
       list; // 当前页的学生集合		public int getCurrentPage() {		return currentPage;	}	public void setCurrentPage(int currentPage) {		this.currentPage = currentPage;	}	public int getTotalPage() {		return totalPage;	}	public void setTotalPage(int totalPage) {		this.totalPage = totalPage;	}	public int getPageSize() {		return pageSize;	}	public void setPageSize(int pageSize) {		this.pageSize = pageSize;	}	public int getTotalSize() {		return totalSize;	}	public void setTotalSize(int totalSize) {		this.totalSize = totalSize;	}	public List
      
        getList() {		return list;	}	public void setList(List
       
         list) {		this.list = list;	}		}复制代码
       
      
     
    

最后就靠显示页面逻辑

<%@ page language="java" contentType="text/html; charset=UTF-8"    pageEncoding="UTF-8"%>     <%@ taglib prefix="c"  uri="http://java.sun.com/jsp/jstl/core"%>
    	
    
		
     				  
     
     
					      
       
				        
										按姓名查询:					 					按性别查询: --请选择-- 男 女 					   										   					添加				
			       
				         
			        
编号
			        
姓名
			        
性别
			        
电话
			        
生日
			        
爱好
			        
简介
			        
操作
		         
		  			         
					        
${stu.sid }
					        
${stu.sname }
					        
${stu.gender }
					        
${stu.phone }
					        
${stu.birthday }
					        
${stu.hobby }
					        
${stu.info }
					        
更新   删除
				         
			  			  			         
			  	        
			  		第 ${pageBean.currentPage } / ${pageBean.totalPage }			  		  			  		每页显示${pageBean.pageSize }条     			  		总的记录数${pageBean.totalSize }    			  					  		
          
          首页 | 
          上一页 
         			  					  		
          
          
            ${i } 
           
           
           ${i } 
           
         			  					  					  		
          
          下一页 | 
          尾页 
         			  	
			         
		        
     
	  
    
复制代码

我的源码

package com.dashucoding.dao;import java.sql.SQLException;import java.util.List;import com.dashucoding.domain.Student;/* * 这是针对学生表的数据访问 *  * */public interface StudentDao {	// 接口中定义的成员都是常量	// 一页显示多少条记录	int PAGE_SIZE = 5;	// 分页dao,查询当页的学生数据	List
    
      findStudentByPage(int currentPage) throws SQLException;	// 根据姓名或性别，查询	List
     
       searchStudent(String sname, String sgender) throws SQLException;	/*	 * 查询所有学生 list
      
       	 */	List
       
         findAll() throws SQLException;	void insert(Student student) throws SQLException;	// sid根据id删除学生	void delete(int sid) throws SQLException;	// 根据id查询单个学生对象	Student findStudentById(int sid) throws SQLException;	// 更新学生信息	void update(Student student) throws SQLException;		// 查询总的学生记录数	int findCount() throws SQLException;}复制代码
       
      
     
    

package com.dashucoding.dao.impl;import java.sql.Connection;import java.sql.SQLException;import java.util.ArrayList;import java.util.List;import org.apache.commons.dbutils.QueryRunner;import org.apache.commons.dbutils.handlers.BeanHandler;import org.apache.commons.dbutils.handlers.BeanListHandler;import org.apache.commons.dbutils.handlers.ScalarHandler;import com.dashucoding.dao.StudentDao;import com.dashucoding.domain.Student;import com.dashucoding.util.JDBCUtil02;import com.dashucoding.util.TextUtils;/* *这是StudentDao的实现,针对前面定义的规范,做出具体的实现 * */public class StudentDaoImpl implements StudentDao {	/*	 * 查询所有学生	 */	@Override	public List
    
      findAll() throws SQLException {		QueryRunner runner = new QueryRunner(JDBCUtil02.getDataSource());		return runner.query("select * from stu", new BeanListHandler
     
      (Student.class));	}	@Override	public void insert(Student student) throws SQLException {		// TODO Auto-generated method stub		QueryRunner runner = new QueryRunner(JDBCUtil02.getDataSource());		runner.update("insert into stu values(null, ?,?,?,?,?,?)", 				student.getSname(), 				student.getGender(),				student.getPhone(), 				student.getBirthday(), 				student.getHobby(), 				student.getInfo()				);	}	@Override	public void delete(int sid) throws SQLException {		// TODO Auto-generated method stub		QueryRunner runner = new QueryRunner(JDBCUtil02.getDataSource());		runner.update("delete from stu where sid=?", sid);			}	@Override	public Student findStudentById(int sid) throws SQLException {		// TODO Auto-generated method stub		QueryRunner runner = new QueryRunner(JDBCUtil02.getDataSource());				return runner.query("select * from stu where sid = ?", new BeanHandler
      
       (Student.class), sid);	}	@Override	public void update(Student student) throws SQLException {		// TODO Auto-generated method stub		QueryRunner runner = new QueryRunner(JDBCUtil02.getDataSource());		runner.update("update stu set sname=?, gender=?, phone=?, birthday=?, hobby=?, info=? where sid=?",				student.getSname(), 				student.getGender(),				student.getPhone(), 				student.getBirthday(), 				student.getHobby(), 				student.getInfo(),				student.getSid());	}	// 模糊查询	@Override	public List
       
         searchStudent(String sname, String sgender) throws SQLException {		// TODO Auto-generated method stub				/*System.out.println(sname + sgender);*/				QueryRunner runner = new QueryRunner(JDBCUtil02.getDataSource());				/*		 * String sql = "select * from stu where sname=? or sgender=?";		 * select * from stu where sname like ?;		 * select * from stu where gender = ?;		 * select * from stu where sname like ? and gender = ?;		 * 如果两个都没有就查询所有		 * sql = "select * from stu"		 * if(姓名){		 *  sql = sql + "where sname like ?";		 * }		 * if(性别){		 *  sql = sql + "where gender = ?";		 * }		 * 		 * String sql = "select * from stu where 1=1";		 * if(姓名){		 *  sql = sql + " and sname like ? ";		 * }		 * if(性别){		 *  sql = sql + " and gender = ? ";		 * }		 * */				String sql = "select * from stu where 1=1";				List
        
          list = new ArrayList
         
          (); if(!TextUtils.isEmpty(sname)) { sql = sql + " and sname like ? "; list.add("%"+sname+"%"); } if(!TextUtils.isEmpty(sgender)) { sql = sql + " and gender = ? "; list.add(sgender); } /*list.toArray()*/ return runner.query(sql, new BeanListHandler
          
           (Student.class),list.toArray()); } @Override public List
           
             findStudentByPage(int currentPage) throws SQLException { // TODO Auto-generated method stub QueryRunner runner = new QueryRunner(JDBCUtil02.getDataSource()); // 第一个问号，一页返回多少条记录，第二个问号，跳过前面的多少条记录 //5 0 --- 第一页 (1-1)*5 //5 5 --- 第二页 (2-1)*5 //5 10 --- 第三页 return runner.query("select * from stu limit ? offset ?", new BeanListHandler
            
             (Student.class),PAGE_SIZE , (currentPage-1)*PAGE_SIZE); } // 查询总的记录数 @Override public int findCount() throws SQLException { // TODO Auto-generated method stub QueryRunner runner = new QueryRunner(JDBCUtil02.getDataSource()); // 用于处理平均值，总的个数 Long result = (Long) runner.query("select count(*) from stu", new ScalarHandler()); return result.intValue(); }}复制代码
            
           
          
         
        
       
      
     
    

package com.dashucoding.domain;import java.util.List;// 一个用于封装了分页的数据// 有： 当前学生集合数据，总的记录数，总的页数，当前页，每页的显示记录数public class PageBean
    
      {	private int currentPage; // 当前页	private int totalPage;// 总页数	private int pageSize;// 每页的记录数，每页要显示多少记录	private int totalSize; // 总的记录数	private List
     
       list; // 当前页的学生集合		public int getCurrentPage() {		return currentPage;	}	public void setCurrentPage(int currentPage) {		this.currentPage = currentPage;	}	public int getTotalPage() {		return totalPage;	}	public void setTotalPage(int totalPage) {		this.totalPage = totalPage;	}	public int getPageSize() {		return pageSize;	}	public void setPageSize(int pageSize) {		this.pageSize = pageSize;	}	public int getTotalSize() {		return totalSize;	}	public void setTotalSize(int totalSize) {		this.totalSize = totalSize;	}	public List
      
        getList() {		return list;	}	public void setList(List
       
         list) {		this.list = list;	}		}复制代码
       
      
     
    

package com.dashucoding.domain;import java.util.Date;/* * 这是学生封装的对象bean *  * */public class Student {		private int sid;	private String sname;	private String gender;	private String phone;	private String hobby;	private String info;	private Date birthday;		public Student() {		super();		// TODO Auto-generated constructor stub	}	public Student(int sid, String sname, String gender, String phone, String hobby, String info, Date birthday) {		super();		this.sid = sid;		this.sname = sname;		this.gender = gender;		this.phone = phone;		this.hobby = hobby;		this.info = info;		this.birthday = birthday;	}				public Student(String sname, String gender, String phone, String hobby, String info, Date birthday) {		super();		this.sname = sname;		this.gender = gender;		this.phone = phone;		this.hobby = hobby;		this.info = info;		this.birthday = birthday;	}	public int getSid() {		return sid;	}	public void setSid(int sid) {		this.sid = sid;	}	public String getSname() {		return sname;	}	public void setSname(String sname) {		this.sname = sname;	}	public String getGender() {		return gender;	}	public void setGender(String gender) {		this.gender = gender;	}	public String getPhone() {		return phone;	}	public void setPhone(String phone) {		this.phone = phone;	}	public String getHobby() {		return hobby;	}	public void setHobby(String hobby) {		this.hobby = hobby;	}	public String getInfo() {		return info;	}	public void setInfo(String info) {		this.info = info;	}	public Date getBirthday() {		return birthday;	}	public void setBirthday(Date birthday) {		this.birthday = birthday;	}	@Override	public String toString() {		return "Student [sid=" + sid + ", sname=" + sname + ", gender=" + gender + ", phone=" + phone + ", hobby="				+ hobby + ", info=" + info + ", birthday=" + birthday + "]";	}			}复制代码

package com.dashucoding.service;import java.sql.SQLException;import java.util.List;import com.dashucoding.domain.PageBean;import com.dashucoding.domain.Student;/* * 这是学生的业务处理规范 * */public interface StudentService {	// 分页dao,查询当页的学生数据	// 分页的很多小逻辑业务 可以做到service里面	// 业务做到service里面，做的就是bean了，当前页，总页数，显示条数， 总记录数	// 返回的是一个bean了	// 返回的是PageBean里面的所有数据了	PageBean findStudentByPage(int currentPage) throws SQLException;	// 根据姓名或性别，查询	List
    
      searchStudent(String sname, String sgender) throws SQLException;	/*	 * 查询所有学生 list
     
      	 */	List
      
        findAll() throws SQLException;	void insert(Student student) throws SQLException;	// sid根据id删除学生	void delete(int sid) throws SQLException;	// 根据id查询单个学生对象	Student findStudentById(int sid) throws SQLException;	// 更新学生信息	void update(Student student) throws SQLException;}复制代码
      
     
    

package com.dashucoding.service.impl;import java.sql.SQLException;import java.util.List;import com.dashucoding.dao.StudentDao;import com.dashucoding.dao.impl.StudentDaoImpl;import com.dashucoding.domain.PageBean;import com.dashucoding.domain.Student;import com.dashucoding.service.StudentService;/* * 这是学生业务实现 * */public class StudentServiceImpl implements StudentService {	@Override	public List
    
      findAll() throws SQLException {		StudentDao dao = new StudentDaoImpl();		return dao.findAll();	}	@Override	public void insert(Student student) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		dao.insert(student);	}	@Override	public void delete(int sid) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		dao.delete(sid);	}	@Override	public Student findStudentById(int sid) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		return dao.findStudentById(sid);	}	@Override	public void update(Student student) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		dao.update(student);	}	@Override	public List
     
       searchStudent(String sname, String sgender) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		return dao.searchStudent(sname, sgender);	}	@Override	public PageBean findStudentByPage(int currentPage) throws SQLException {		// TODO Auto-generated method stub		// 封装分页的该页的数据		PageBean
      
        pageBean = new PageBean
       
        ();				int pageSize = StudentDao.PAGE_SIZE;				// 设置当前页		pageBean.setCurrentPage(currentPage);		// 每条记录		pageBean.setPageSize(pageSize);				StudentDao dao = new StudentDaoImpl();		List
        
          list = dao.findStudentByPage(currentPage);		pageBean.setList(list);		// 总记录数，总页数		int count = dao.findCount();		pageBean.setTotalSize(count);				// 总页数		pageBean.setTotalPage(count % pageSize == 0 ? count / pageSize : (count / pageSize) + 1);				return null;	}}复制代码
        
       
      
     
    

package com.dashucoding.servlet;import java.io.IOException;import java.text.SimpleDateFormat;import java.util.Arrays;import java.util.Date;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.dashucoding.domain.Student;import com.dashucoding.service.StudentService;import com.dashucoding.service.impl.StudentServiceImpl;/** * 用于处理学生的添加请求 */public class AddServlet extends HttpServlet {	protected void doGet(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {		request.setCharacterEncoding("UTF-8");		try {			// 1. 获取客户端提交上来的数据			String sname = request.getParameter("sname");			String gender = request.getParameter("gender");			String phone = request.getParameter("phone");			String birthday = request.getParameter("birthday");			String info = request.getParameter("info");			// String hobby = request.getParameter("hobby");//hobby : 游泳，写字， 足球。			String[] h = request.getParameterValues("hobby");			String hobby = Arrays.toString(h);			hobby = hobby.substring(1, hobby.length() - 1);			// 2. 添加到数据库			// string -- date			Date date = new SimpleDateFormat("yyyy-MM-dd").parse(birthday);			Student student = new Student(sname, gender, phone, hobby, info, date);			StudentService service = new StudentServiceImpl();			service.insert(student);			// 3. 跳转到列表页			request.getRequestDispatcher("StudentListServlet").forward(request, response);		} catch (Exception e) {			e.printStackTrace();		}	}	protected void doPost(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {		doGet(request, response);	}}复制代码

package com.dashucoding.servlet;import java.io.IOException;import java.sql.SQLException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.dashucoding.service.StudentService;import com.dashucoding.service.impl.StudentServiceImpl;/** * 用于处理删除学生 */public class DeleteServlet extends HttpServlet {	protected void doGet(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {		try {			int sid = Integer.parseInt(request.getParameter("sid"));			// System.out.println("sid="+sid);			// 执行删除			StudentService service = new StudentServiceImpl();			service.delete(sid);			// 跳转到列表页			request.getRequestDispatcher("StudentListServlet").forward(request, response);		} catch (SQLException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}	}	protected void doPost(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {		doGet(request, response);	}}复制代码

package com.dashucoding.servlet;import java.io.IOException;import java.sql.SQLException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.dashucoding.domain.Student;import com.dashucoding.service.StudentService;import com.dashucoding.service.impl.StudentServiceImpl;/** * 处理单个学生的更新，查询学生的信息，跳转到更新的页面 */public class EditServlet extends HttpServlet {	protected void doGet(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {		try {			// 接收id			int sid = Integer.parseInt(request.getParameter("sid"));			// 查询学生数据			StudentService service = new StudentServiceImpl();			Student stu = service.findStudentById(sid);			// 显示数据			// 存储数据			request.setAttribute("stu", stu);			// 跳转			request.getRequestDispatcher("edit.jsp").forward(request, response);		} catch (SQLException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}	}	/**	 * @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);	}}复制代码

package com.dashucoding.servlet;import java.io.IOException;import java.sql.SQLException;import java.util.List;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.dashucoding.domain.Student;import com.dashucoding.service.StudentService;import com.dashucoding.service.impl.StudentServiceImpl;/** * Servlet implementation class SearchStudentServlet */public class SearchStudentServlet extends HttpServlet {	protected void doGet(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {		request.setCharacterEncoding("UTF-8");		try {			// 取到了要查询的关键数据			String sname = request.getParameter("sname");			String sgender = request.getParameter("sgender");			// 找service查询			StudentService service = new StudentServiceImpl();			List
    
      list = service.searchStudent(sname, sgender);						/*for(Student student : list) {				System.out.println("stu=" + student);			}*/						request.setAttribute("list", list);			// 跳转界面			request.getRequestDispatcher("list.jsp").forward(request, response);		} catch (SQLException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}	}	protected void doPost(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {		// TODO Auto-generated method stub		doGet(request, response);	}}复制代码
    

package com.dashucoding.servlet;import java.io.IOException;import java.sql.SQLException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.dashucoding.domain.PageBean;import com.dashucoding.service.StudentService;import com.dashucoding.service.impl.StudentServiceImpl;/** * 这是用于分页显示学生列表的servlet */public class StudentListPageServlet extends HttpServlet {		protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {		try {			//1. 获取需要显示的页码数			int currentPage =Integer.parseInt( request.getParameter("currentPage"));						//2. 根据指定的页数，去获取该页的数据回来			//List
    
      --- list.jsp						StudentService service = new StudentServiceImpl();			PageBean pageBean= service.findStudentByPage(currentPage);			request.setAttribute("pageBean", pageBean);			//3. 跳转界面。			request.getRequestDispatcher("list_page.jsp").forward(request, response);		} catch (SQLException e) {			e.printStackTrace();		}	}		protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {		// TODO Auto-generated method stub		doGet(request, response);	}	}复制代码
    

package com.dashucoding.servlet;import java.io.IOException;import java.sql.SQLException;import java.util.List;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.dashucoding.dao.StudentDao;import com.dashucoding.dao.impl.StudentDaoImpl;import com.dashucoding.domain.Student;import com.dashucoding.service.StudentService;import com.dashucoding.service.impl.StudentServiceImpl;public class StudentListServlet extends HttpServlet {	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {		try {			// 查询所有的学生			StudentService service = new StudentServiceImpl();			List
    
      list = service.findAll();			// 把数据存储到作用域中			request.setAttribute("list", list);						// 跳转页面			request.getRequestDispatcher("list.jsp").forward(request,response);		} catch (SQLException e) {			// TODO Auto-generated catch block			e.printStackTrace();		}	}	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {		doGet(request, response);	}}复制代码
    

package com.dashucoding.servlet;import java.io.IOException;import java.text.SimpleDateFormat;import java.util.Arrays;import java.util.Date;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import com.dashucoding.domain.Student;import com.dashucoding.service.StudentService;import com.dashucoding.service.impl.StudentServiceImpl;/** * Servlet implementation class UpdateServlet */public class UpdateServlet extends HttpServlet {	protected void doGet(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {		request.setCharacterEncoding("UTF-8");		try {			// 1. 获取客户端提交上来的数据			int sid = Integer.parseInt(request.getParameter("sid"));			String sname = request.getParameter("sname");			String gender = request.getParameter("gender");			String phone = request.getParameter("phone");			String birthday = request.getParameter("birthday"); 			String info = request.getParameter("info");			// String hobby = request.getParameter("hobby");			String[] h = request.getParameterValues("hobby");			String hobby = Arrays.toString(h);			hobby = hobby.substring(1, hobby.length() - 1);			// 2. 添加到数据库			Date date = new SimpleDateFormat("yyyy-MM-dd").parse(birthday);			Student student = new Student(sid, sname, gender, phone, hobby, info, date);			// 2. 更新数据库数据			StudentService service = new StudentServiceImpl();			service.update(student);			// 3. 跳转界面			request.getRequestDispatcher("StudentListServlet").forward(request, response);		} catch (Exception e) {			e.printStackTrace();		}	}	protected void doPost(HttpServletRequest request, HttpServletResponse response)			throws ServletException, IOException {		// TODO Auto-generated method stub		doGet(request, response);	}}复制代码

package com.dashucoding.util;import java.io.FileInputStream;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;import javax.sql.DataSource;import com.mchange.v2.c3p0.ComboPooledDataSource;public class JDBCUtil02 {		static ComboPooledDataSource dataSource = null;	static {		dataSource = new ComboPooledDataSource();	}		public static DataSource getDataSource() {		return dataSource;	}	/**	 * 获取连接对象	 * @return	 * @throws SQLException 	 */	public static Connection getConn() throws SQLException{				return dataSource.getConnection();	}		/**	 * 释放资源	 * @param conn	 * @param st	 * @param rs	 */	public static void release(Connection conn , Statement st , ResultSet rs){		closeRs(rs);		closeSt(st);		closeConn(conn);	}	public static void release(Connection conn , Statement st){		closeSt(st);		closeConn(conn);	}		private static void closeRs(ResultSet rs){		try {			if(rs != null){				rs.close();			}		} catch (SQLException e) {			e.printStackTrace();		}finally{			rs = null;		}	}		private static void closeSt(Statement st){		try {			if(st != null){				st.close();			}		} catch (SQLException e) {			e.printStackTrace();		}finally{			st = null;		}	}		private static void closeConn(Connection conn){		try {			if(conn != null){				conn.close();			}		} catch (SQLException e) {			e.printStackTrace();		}finally{			conn = null;		}	}}复制代码

package com.dashucoding.util;public class TextUtils {	/**	 * 判断某一个字符串是否为空。	 * 	 * @param s	 * @return	 */	public static boolean isEmpty(CharSequence s) {		return s == null || s.length() == 0;	}}复制代码

<%@ page language="java" contentType="text/html; charset=UTF-8"	pageEncoding="UTF-8"%>
    	
    
		
     
			      
       
				        
姓名
				        
			       
			       
				        
性别
				        
男 女
			       
			       
				        
电话
				        
			       
			       
				        
生日
				        
			       
			       
				        
爱好
				        
游泳 篮球 足球 看书 写字
			       
			       
				        
简介
				        
			       
			       
				        
			       
		      
     
	
    
复制代码

<%@ page language="java" contentType="text/html; charset=UTF-8"    pageEncoding="UTF-8"%>     <%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %> <%@ taglib prefix="fn" uri="http://java.sun.com/jsp/jstl/functions" %> 
    
更新学生页面
    
	
       
     
        
       
	        
姓名
	        
         
         
	        
性别
	        
		
         
          checked
         >男		
         
          checked
         >女	
         
         
	        
电话
	        
         
         
	        
生日
	        
         
         
	        
爱好
			        
		
         
          checked
         >游泳		
         
          checked
         >篮球		
         
          checked
         >足球		
         
          checked
         >看书		
         
          checked
         >写字		
         
         
	        
简介
	        
${stu.info }
         
         
	        
  
         
        
     
   
    
复制代码

<%@ page language="java" contentType="text/html; charset=UTF-8"    pageEncoding="UTF-8"%>
    
显示所有学生列表
分页显示所有学生
复制代码

<%@ page language="java" contentType="text/html; charset=UTF-8"    pageEncoding="UTF-8"%>     <%@ taglib prefix="c"  uri="http://java.sun.com/jsp/jstl/core"%>
    	
    
		
     				  
     
     
					      
       
				        
										按姓名查询:					 					按性别查询: --请选择-- 男 女 					   										   					添加				
			       
				         
			        
编号
			        
姓名
			        
性别
			        
电话
			        
生日
			        
爱好
			        
简介
			        
操作
		         
		  			         
					        
${stu.sid }
					        
${stu.sname }
					        
${stu.gender }
					        
${stu.phone }
					        
${stu.birthday }
					        
${stu.hobby }
					        
${stu.info }
					        
更新   删除
				         
			  		        
     
	  
    
复制代码

<%@ page language="java" contentType="text/html; charset=UTF-8"	pageEncoding="UTF-8"%><%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
    	
    
		
     				
     
     
			      
       
				        
按姓名查询:  					按性别查询: --请选择-- 男 女      					    添加				
			       
			       
				        
编号
				        
姓名
				        
性别
				        
电话
				        
生日
				        
爱好
				        
简介
				        
操作
			       
			       
					        
${stu.sid }
					        
${stu.sname }
					        
${stu.gender }
					        
${stu.phone }
					        
${stu.birthday }
					        
${stu.hobby }
					        
${stu.info }
					        
更新 删除
				       
						       
				        
第 ${pageBean.currentPage } /					${pageBean.totalPage }    每页显示${pageBean.pageSize }条					    总的记录数${pageBean.totalSize }     
          
          首页 | 
          上一页 
          
          
          
            ${i } 
           
           
           ${i } 
           
          
          
          下一页 | 
          尾页 
         				
			       
		      
     
	
    
复制代码

package com.dashucoding.service.impl;import java.sql.SQLException;import java.util.List;import com.dashucoding.dao.StudentDao;import com.dashucoding.dao.impl.StudentDaoImpl;import com.dashucoding.domain.PageBean;import com.dashucoding.domain.Student;import com.dashucoding.service.StudentService;/* * 这是学生业务实现 * */public class StudentServiceImpl implements StudentService {	@Override	public List
    
      findAll() throws SQLException {		StudentDao dao = new StudentDaoImpl();		return dao.findAll();	}	@Override	public void insert(Student student) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		dao.insert(student);	}	@Override	public void delete(int sid) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		dao.delete(sid);	}	@Override	public Student findStudentById(int sid) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		return dao.findStudentById(sid);	}	@Override	public void update(Student student) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		dao.update(student);	}	@Override	public List
     
       searchStudent(String sname, String sgender) throws SQLException {		// TODO Auto-generated method stub		StudentDao dao = new StudentDaoImpl();		return dao.searchStudent(sname, sgender);	}	@Override	public PageBean findStudentByPage(int currentPage) throws SQLException {		// 封装分页的该页数据		PageBean
      
        pageBean = new PageBean
       
        ();		int pageSize = StudentDao.PAGE_SIZE;		pageBean.setCurrentPage(currentPage); 		// 设置当前页		pageBean.setPageSize(pageSize); 		// 设置每页显示多少记录		StudentDao dao = new StudentDaoImpl();		List
        
          list = dao.findStudentByPage(currentPage);		pageBean.setList(list); 		// 设置这一页的学生数据		// 总的记录数， 总的页数。		int count = dao.findCount();		pageBean.setTotalSize(count); 		// 设置总的记录数		pageBean.setTotalPage(count % pageSize == 0 ? count / pageSize : (count / pageSize) + 1); // 总页数		return pageBean;	}}复制代码
        
       
      
     
    

结言

好了，欢迎在留言区留言，与大家分享你的经验和心得。

感谢你学习今天的内容，如果你觉得这篇文章对你有帮助的话，也欢迎把它分享给更多的朋友，感谢。

达叔小生：往后余生，唯独有你 You and me, we are family ! 90后帅气小伙，良好的开发习惯；独立思考的能力；主动并且善于沟通 简书博客： 达叔小生

结语

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