JAVAWEB开发之分页显示、批量删除、条件查询 以及Listener监听器

（4）分页查询

<?xml version="1.0" encoding="UTF-8"?>
<c3p0-config><default-config><property name="driverClass">com.mysql.jdbc.Driver</property><property name="jdbcUrl">jdbc:mysql:///mydb1</property><property name="user">root</property><property name="password">root</property></default-config></c3p0-config>

<?xml version="1.0" encoding="UTF-8"?>
<taglib version="2.1" 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-jsptaglibrary_2_1.xsd"><tlib-version>1.0</tlib-version><short-name>my</short-name><uri>http://www.itcast.cn/tag</uri><tag><name>sex</name><!-- 标签名称 --><tag-class>cn.itcast.customer.tag.GenderTag</tag-class><!-- 标签类 --><body-content>empty</body-content><!-- 标签体中内容 --><attribute><name>gender</name> <!-- 属性名称 --><required>true</required> <!-- 属性必须有 --><rtexprvalue>true</rtexprvalue><!-- 属性值可以接收el表达式 --></attribute></tag><!-- 分页标签 --><tag><name>page</name><tag-class>cn.itcast.customer.tag.PageTag</tag-class><body-content>empty</body-content><attribute><name>pb</name><required>true</required> <!-- 属性必须有 --><rtexprvalue>true</rtexprvalue><!-- 属性值可以接收el表达式 --></attribute></tag>
</taglib>

<?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"><display-name></display-name><servlet><servlet-name>CustomerFindAllServlet</servlet-name><servlet-class>cn.itcast.customer.web.servlet.CustomerFindAllServlet</servlet-class></servlet><servlet><servlet-name>CustomerDelByIdServlet</servlet-name><servlet-class>cn.itcast.customer.web.servlet.CustomerDelByIdServlet</servlet-class></servlet><servlet><servlet-name>CustomerFindByIdServlet</servlet-name><servlet-class>cn.itcast.customer.web.servlet.CustomerFindByIdServlet</servlet-class></servlet><servlet><servlet-name>CustomerUpdateServlet</servlet-name><servlet-class>cn.itcast.customer.web.servlet.CustomerUpdateServlet</servlet-class></servlet><servlet><servlet-name>CustomerAddServlet</servlet-name><servlet-class>cn.itcast.customer.web.servlet.CustomerAddServlet</servlet-class></servlet><servlet><servlet-name>CustomerDelSelectServlet</servlet-name><servlet-class>cn.itcast.customer.web.servlet.CustomerDelSelectServlet</servlet-class></servlet><servlet><servlet-name>CustomerSimpleSelectServlet</servlet-name><servlet-class>cn.itcast.customer.web.servlet.CustomerSimpleSelectServlet</servlet-class></servlet><servlet><servlet-name>CustomerFindAllByPageServlet</servlet-name><servlet-class>cn.itcast.customer.web.servlet.CustomerFindAllByPageServlet</servlet-class></servlet><servlet-mapping><servlet-name>CustomerFindAllServlet</servlet-name><url-pattern>/findAll</url-pattern></servlet-mapping><servlet-mapping><servlet-name>CustomerDelByIdServlet</servlet-name><url-pattern>/delById</url-pattern></servlet-mapping><servlet-mapping><servlet-name>CustomerFindByIdServlet</servlet-name><url-pattern>/findById</url-pattern></servlet-mapping><servlet-mapping><servlet-name>CustomerUpdateServlet</servlet-name><url-pattern>/update</url-pattern></servlet-mapping><servlet-mapping><servlet-name>CustomerAddServlet</servlet-name><url-pattern>/add</url-pattern></servlet-mapping><servlet-mapping><servlet-name>CustomerDelSelectServlet</servlet-name><url-pattern>/delSelect</url-pattern></servlet-mapping><servlet-mapping><servlet-name>CustomerSimpleSelectServlet</servlet-name><url-pattern>/simpleSelect</url-pattern></servlet-mapping><servlet-mapping><servlet-name>CustomerFindAllByPageServlet</servlet-name><url-pattern>/findAllByPage</url-pattern></servlet-mapping>	<welcome-file-list><welcome-file>index.jsp</welcome-file></welcome-file-list>
</web-app>

package cn.itcast.customer.utils;import java.sql.Connection;
import java.sql.SQLException;import javax.sql.DataSource;import com.mchange.v2.c3p0.ComboPooledDataSource;public class DataSourceUtils {private static ComboPooledDataSource cpds = new ComboPooledDataSource();public static Connection getConnection() throws SQLException {return cpds.getConnection();}public static DataSource getDataSource() {return cpds;}}

package cn.itcast.customer.utils;import java.util.UUID;public class IdUtils {public static String getUUID(){return UUID.randomUUID().toString().replaceAll("-","");}// public static void main(String[] args) {// System.out.println(getUUID());// }
}

package cn.itcast.customer.tag;import java.io.IOException;import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.SimpleTagSupport;public class GenderTag extends SimpleTagSupport {private String gender;public String getGender() {return gender;}public void setGender(String gender) {this.gender = gender;}@Overridepublic void doTag() throws JspException, IOException {StringBuffer buff = new StringBuffer();if ("男".equals(gender)) {buff.append("<input type='radio' name='gender' value='男' checked='checked'>男<input type='radio' name='gender' value='女'>女<br>");} else {buff.append("<input type='radio' name='gender' value='男'>男<input type='radio' name='gender' value='女' checked='checked'>女<br>");}this.getJspContext().getOut().write(buff.toString());}
}

package cn.itcast.customer.tag;import java.io.IOException;import javax.servlet.jsp.JspException;
import javax.servlet.jsp.tagext.SimpleTagSupport;import cn.itcast.customer.domain.PageBean;public class PageTag extends SimpleTagSupport {private PageBean pb;public PageBean getPb() {return pb;}public void setPb(PageBean pb) {this.pb = pb;}@Overridepublic void doTag() throws JspException, IOException {StringBuffer buff = new StringBuffer();int totalPage = pb.getTotalPage();int pageNum = pb.getPageNum(); // 当前页码if (pageNum - 5 >= 0) {for (int i = pageNum-5; i < pageNum+4; i++) {if (i + 1 == pb.getPageNum()) {buff.append("<a href='/day20_1/findAllByPage?pageNum="+ (i + 1) + "¤tPage=" + pb.getCurrentPage()+ "'><font color='green'>" + (i + 1)+ "</font></a>  ");} else {buff.append("<a href='/day20_1/findAllByPage?pageNum="+ (i + 1) + "¤tPage=" + pb.getCurrentPage()+ "'>" + (i + 1) + "</a>  ");}}} else if (pageNum - 5 < 0) {for (int i = 0; i < pageNum; i++) {if (i + 1 == pb.getPageNum()) {buff.append("<a href='/day20_1/findAllByPage?pageNum="+ (i + 1) + "¤tPage=" + pb.getCurrentPage()+ "'><font color='green'>" + (i + 1)+ "</font></a>  ");} else {buff.append("<a href='/day20_1/findAllByPage?pageNum="+ (i + 1) + "¤tPage=" + pb.getCurrentPage()+ "'>" + (i + 1) + "</a>  ");}}for (int i = pageNum; i < (pageNum + 4); i++) {if (i + 1 == pb.getPageNum()) {buff.append("<a href='/day20_1/findAllByPage?pageNum="+ (i + 1) + "¤tPage=" + pb.getCurrentPage()+ "'><font color='green'>" + (i + 1)+ "</font></a>  ");} else {buff.append("<a href='/day20_1/findAllByPage?pageNum="+ (i + 1) + "¤tPage=" + pb.getCurrentPage()+ "'>" + (i + 1) + "</a>  ");}}}this.getJspContext().getOut().write(buff.toString());}
}

package cn.itcast.customer;import java.sql.SQLException;import javax.sql.DataSource;import org.apache.commons.dbutils.QueryRunner;
import org.junit.Test;import cn.itcast.customer.utils.DataSourceUtils;
import cn.itcast.customer.utils.IdUtils;public class Demo {@Testpublic void add() throws SQLException {QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());for (int i = 0; i < 100; i++) {runner.update("insert into customer(id) values(?)",IdUtils.getUUID());}}
}

package cn.itcast.customer.dao;import java.sql.SQLException;
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 cn.itcast.customer.domain.Customer;
import cn.itcast.customer.utils.DataSourceUtils;public class CustomerDao {// 查询所有客户public List<Customer> findAll() throws SQLException {String sql = "select * from customer";QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());return runner.query(sql, new BeanListHandler<Customer>(Customer.class));}public void delById(String id) throws SQLException {String sql = "delete from customer where id=?";QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());runner.update(sql, id);}public Customer findById(String id) throws SQLException {String sql = "select * from customer where id=?";QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());return runner.query(sql, new BeanHandler<Customer>(Customer.class), id);}public void update(Customer c) throws SQLException {String sql = "update customer set name=?,gender=?,birthday=?,cellphone=?,email=?,preference=?,type=?,description=? where id=?";QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());runner.update(sql, c.getName(), c.getGender(), c.getBirthday(),c.getCellphone(), c.getEmail(), c.getPreference(), c.getType(),c.getDescription(), c.getId());}public void add(Customer c) throws SQLException {String sql = "insert into customer values(?,?,?,?,?,?,?,?,?)";QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());runner.update(sql, c.getId(), c.getName(), c.getGender(),c.getBirthday(), c.getCellphone(), c.getEmail(),c.getPreference(), c.getType(), c.getDescription());}public void delSelect(String[] id) throws SQLException {String sql = "delete from customer where id=?";QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());Object[][] ids = new Object[id.length][1];for (int i = 0; i < id.length; i++) {ids[i][0] = id[i];}runner.batch(sql, ids);}// 条件查询// field 相当于字段名称// msg 相当于字段值public List<Customer> simpleSelect(String field, String msg)throws SQLException {String sql = "select * from customer where " + field + "  like ?";QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());return runner.query(sql, new BeanListHandler<Customer>(Customer.class),"%" + msg + "%");}// pagNum 页码// currentPage 每页条数public List<Customer> findByPage(int pageNum, int currentPage)throws SQLException {String sql = "select * from customer limit ?,?";QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());return runner.query(sql, new BeanListHandler<Customer>(Customer.class),(pageNum - 1) * currentPage, currentPage);}// 查询总条数public int findAllCount() throws SQLException {String sql = "select count(*)  from customer";QueryRunner runner = new QueryRunner(DataSourceUtils.getDataSource());long count = (Long) runner.query(sql, new ScalarHandler());return (int) count;}}

package cn.itcast.customer.domain;import java.util.Date;public class Customer {// Id 编号 varchar(40)// name 客户姓名 varchar(20)// gender 性别 varchar(10)// birthday 生日 date// cellphone 手机 varchar(20)// email 电子邮件 varchar(40)// preference 客户爱好 varchar(100)// type 客户类型 varchar(40)// description 备注 varchar(255)private String id;private String name;private String gender;private Date birthday;private String cellphone;private String email;private String preference;private String type;private String description;public String getId() {return id;}public void setId(String id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}public String getGender() {return gender;}public void setGender(String gender) {this.gender = gender;}public Date getBirthday() {return birthday;}public void setBirthday(Date birthday) {this.birthday = birthday;}public String getCellphone() {return cellphone;}public void setCellphone(String cellphone) {this.cellphone = cellphone;}public String getEmail() {return email;}public void setEmail(String email) {this.email = email;}public String getPreference() {return preference;}public void setPreference(String preference) {this.preference = preference;}public String getType() {return type;}public void setType(String type) {this.type = type;}public String getDescription() {return description;}public void setDescription(String description) {this.description = description;}@Overridepublic String toString() {return "Customer [id=" + id + ", name=" + name + ", gender=" + gender+ ", birthday=" + birthday + ", cellphone=" + cellphone+ ", email=" + email + ", preference=" + preference + ", type="+ type + ", description=" + description + "]";}}

package cn.itcast.customer.domain;import java.util.List;public class PageBean {private int pageNum; // 页码private int currentPage; // 每页条数private int totalPage; // 总页数private int totalCount; // 总条数private List<Customer> cs; // 每页数据public int getPageNum() {return pageNum;}public void setPageNum(int pageNum) {this.pageNum = pageNum;}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 getTotalCount() {return totalCount;}public void setTotalCount(int totalCount) {this.totalCount = totalCount;}public List<Customer> getCs() {return cs;}public void setCs(List<Customer> cs) {this.cs = cs;}}

package cn.itcast.customer.service;import java.sql.SQLException;
import java.util.List;import cn.itcast.customer.dao.CustomerDao;
import cn.itcast.customer.domain.Customer;
import cn.itcast.customer.domain.PageBean;public class CustomerService {private CustomerDao dao = new CustomerDao();// 查询所有客户信息操作public List<Customer> findAll() throws SQLException {return dao.findAll();}// 根据id删除public void delById(String id) throws SQLException {dao.delById(id);}// 根据id查询public Customer findById(String id) throws SQLException {return dao.findById(id);}// 修改客户信息public void update(Customer c) throws SQLException {dao.update(c);}// 添加客户信息public void add(Customer c) throws SQLException {dao.add(c);}// 批量删除public void delSelect(String[] id) throws SQLException {dao.delSelect(id);}// 条件查询public List<Customer> simpleSelect(String field, String msg)throws SQLException {return dao.simpleSelect(field, msg);}// 分页操作// pageNum 页码// currentPage 每页条数public PageBean findByPage(int pageNum, int currentPage)throws SQLException {PageBean pb = new PageBean();List<Customer> cs = dao.findByPage(pageNum, currentPage);// 查询总条数:int totalCount = dao.findAllCount();// 得到总页数int totalPage = (int) Math.ceil(totalCount * 1.0 / currentPage);pb.setTotalCount(totalCount); // 封装总条数pb.setTotalPage(totalPage);// 封装总页数pb.setCs(cs);// 封装当前页数据.pb.setCurrentPage(currentPage); // 封装每页条数pb.setPageNum(pageNum);// 封装当前页码return pb;}}

package cn.itcast.customer.web.servlet;import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.sql.SQLException;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.beanutils.ConvertUtils;
import org.apache.commons.beanutils.converters.DateConverter;import cn.itcast.customer.domain.Customer;
import cn.itcast.customer.service.CustomerService;
import cn.itcast.customer.utils.IdUtils;public class CustomerAddServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {request.setCharacterEncoding("utf-8");// 1.得到所有请求参数，封装到javaBeanCustomer c = new Customer();DateConverter dc = new DateConverter(); // 这是一个日期类型转换器.dc.setPattern("yyyy-MM-dd");try {ConvertUtils.register(dc, java.util.Date.class);BeanUtils.populate(c, request.getParameterMap());} catch (IllegalAccessException e) {e.printStackTrace();} catch (InvocationTargetException e) {e.printStackTrace();}// 需要手动将id封装到Customer对象.c.setId(IdUtils.getUUID());// 2.调用serivce完成添加操作CustomerService service = new CustomerService();try {service.add(c);// 添加成功response.sendRedirect(request.getContextPath() + "/findAll");return;} catch (SQLException e) {e.printStackTrace();request.setAttribute("add.message", "添加客户信息失败");request.getRequestDispatcher("/add.jsp").forward(request, response);return;}}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}}

package cn.itcast.customer.web.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 cn.itcast.customer.service.CustomerService;public class CustomerDelByIdServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {response.setContentType("text/html;charset=utf-8");// 1.得到要删除的idString id = request.getParameter("id");// 2.调用service中根据id删除的方法CustomerService service = new CustomerService();try {service.delById(id);// 跳转到CustomerFindAllServlet,就是要重新查询一次response.sendRedirect(request.getContextPath() + "/findAll");return;} catch (SQLException e) {e.printStackTrace();response.getWriter().write("删除失败");return;}}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}}

package cn.itcast.customer.web.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 cn.itcast.customer.service.CustomerService;public class CustomerDelSelectServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {response.setContentType("text/html;charset=utf-8");// 1.得到所有要删除的客户的idString[] id = request.getParameterValues("ck");// 2.调用service，完成批量删除CustomerService service = new CustomerService();try {service.delSelect(id);response.sendRedirect(request.getContextPath() + "/findAll");return;} catch (SQLException e) {e.printStackTrace();response.getWriter().write("批量删除失败");return;}}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}}

package cn.itcast.customer.web.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 cn.itcast.customer.domain.Customer;
import cn.itcast.customer.domain.PageBean;
import cn.itcast.customer.service.CustomerService;public class CustomerFindAllByPageServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {System.out.println(request.getRemoteAddr());// 1.默认访问第一页int pageNum = 1;String _pageNum = request.getParameter("pageNum");if (_pageNum != null) {pageNum = Integer.parseInt(_pageNum);}// 2.每页条数 人为定义int currentPage = 5;String _currentPage = request.getParameter("currentPage");if (_currentPage != null) {currentPage = Integer.parseInt(_currentPage);}// 3.调用service,完成查询当前页数据操作CustomerService service = new CustomerService();try {PageBean pb = service.findByPage(pageNum, currentPage);// 4.将数据存储到request域，请求转到到页面展示。request.setAttribute("pb", pb);request.getRequestDispatcher("/showCustomerByPage.jsp").forward(request, response);return;} catch (SQLException e) {e.printStackTrace();}}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}}

package cn.itcast.customer.web.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 cn.itcast.customer.domain.Customer;
import cn.itcast.customer.service.CustomerService;public class CustomerFindAllServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {response.setContentType("text/html;charset=utf-8");// 调用servic中查询所有方法CustomerService service = new CustomerService();try {List<Customer> cs = service.findAll();request.setAttribute("cs", cs);request.getRequestDispatcher("/showCustomer.jsp").forward(request,response);return;} catch (SQLException e) {e.printStackTrace();response.getWriter().write("查询客户信息失败");return;}}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}}

package cn.itcast.customer.web.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 cn.itcast.customer.domain.Customer;
import cn.itcast.customer.service.CustomerService;public class CustomerFindByIdServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {response.setContentType("text/html;charset=utf-8");// 1.得到要查询的idString id = request.getParameter("id");// 2.调用service中根据id查询的方法.CustomerService service = new CustomerService();try {Customer c = service.findById(id);request.setAttribute("c", c);request.getRequestDispatcher("/customerInfo.jsp").forward(request,response);return;} catch (SQLException e) {e.printStackTrace();response.getWriter().write("根据id查询失败");return;}}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}}

package cn.itcast.customer.web.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 cn.itcast.customer.domain.Customer;
import cn.itcast.customer.service.CustomerService;public class CustomerSimpleSelectServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {response.setContentType("text/html;charset=utf-8");request.setCharacterEncoding("utf-8");// 1.得到请求参数String field = request.getParameter("field"); // 字段名称String msg = request.getParameter("msg"); // 字段值// 2.调用service完成查询操作CustomerService service = new CustomerService();try {List<Customer> cs = service.simpleSelect(field, msg);request.setAttribute("cs", cs);request.getRequestDispatcher("/showCustomer.jsp").forward(request,response);return;} catch (SQLException e) {e.printStackTrace();response.getWriter().write("条件查询失败");return;}}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}}

package cn.itcast.customer.web.servlet;import java.io.IOException;
import java.lang.reflect.InvocationTargetException;
import java.sql.SQLException;import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.beanutils.ConvertUtils;
import org.apache.commons.beanutils.converters.DateConverter;import cn.itcast.customer.domain.Customer;
import cn.itcast.customer.service.CustomerService;public class CustomerUpdateServlet extends HttpServlet {public void doGet(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {// 处理请求编码，request.setCharacterEncoding("utf-8");response.setContentType("text/html;charset=utf-8");// 1.得到所有请求参数 ，封装到javaBean中.Customer c = new Customer();DateConverter dc = new DateConverter(); // 这是一个日期类型转换器.dc.setPattern("yyyy-MM-dd");try {ConvertUtils.register(dc, java.util.Date.class);BeanUtils.populate(c, request.getParameterMap());} catch (IllegalAccessException e) {e.printStackTrace();} catch (InvocationTargetException e) {e.printStackTrace();}// 调用service中修改操作CustomerService service = new CustomerService();try {service.update(c);// 跳转到CustomerFindAllServlet,就是要重新查询一次response.sendRedirect(request.getContextPath() + "/findAll");return;} catch (SQLException e) {e.printStackTrace();response.getWriter().write("修改失败");return;}}public void doPost(HttpServletRequest request, HttpServletResponse response)throws ServletException, IOException {doGet(request, response);}}

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib  prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@taglib  prefix="my" uri="http://www.itcast.cn/tag"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html><head><script language="javascript" type="text/javascript" src="${pageContext.request.contextPath}/My97DatePicker/WdatePicker.js"></script><title>My JSP 'index.jsp' starting page</title></head><body>${requestScope["add.message"]}<br><form action="${pageContext.request.contextPath}/add" method="post">		客户姓名:<input type="text" name="name"><br>		客户性别:<input type="radio" name="gender" value="男" checked="checked">男<input type="radio" name="gender" value="女">女	<br>		客户生日:<input type="text" name="birthday" class="Wdate" οnclick="WdatePicker()" readonly="readonly"><br>客户电话:<input type="text" name="cellphone"><br>客户邮箱:<input type="text" name="email"><br>客户爱好:<input type="text" name="preference"><br>客户类型:<input type="text" name="type"><br>客户备注:<input type="text" name="description"><br><input type="submit" value="添加"></form></body>
</html>

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib  prefix="c" uri="http://java.sun.com/jsp/jstl/core"%>
<%@taglib  prefix="my" uri="http://www.itcast.cn/tag"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html><head><title>My JSP 'index.jsp' starting page</title></head><body><form action="${pageContext.request.contextPath}/update" method="post"><input type="hidden" name="id" value="${c.id}">客户姓名:<input type="text" name="name" value="${c.name}"><br>客户性别:<my:sex gender="${c.gender}"/><%--<c:if test="${c.gender=='男'}"><input type="radio" name="gender" value="男" checked="checked">男<input type="radio" name="gender" value="女">女</c:if><c:if test="${c.gender!='男'}"><input type="radio" name="gender" value="男">男<input type="radio" name="gender" value="女" checked="checked">女</c:if>		--%>客户生日:<input type="text" name="birthday" value="${c.birthday}"><br>客户电话:<input type="text" name="cellphone" value="${c.cellphone}"><br>客户邮箱:<input type="text" name="email" value="${c.email}"><br>客户爱好:<input type="text" name="preference" value="${c.preference}"><br>客户类型:<input type="text" name="type" value="${c.type}"><br>客户备注:<input type="text" name="description" value="${c.description}"><br><input type="submit" value="修改"></form></body>
</html>

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head><title>My JSP 'index.jsp' starting page</title><script type="text/javascript">function del(id) {var flag = window.confirm("确认删除吗");if (flag) {//确认删除location.href = "${pageContext.request.contextPath}/delById?id="+ id;}};function change() {//1.得到id为main的这个checkboxvar main = document.getElementById("main");var flag = main.checked;//2.得到所有name=ck的checkboxvar cks = document.getElementsByName("ck");//3.将cks中所有的checkbox的checked值设置为flagfor ( var i = 0; i < cks.length; i++) {cks[i].checked = flag;}};function sendDel(){document.getElementById("f").submit();//表单提交var cks = document.getElementsByName("ck");/*var url="${pageContext.request.contextPath}/delSelect?";for(var i=0;i<cks.length;i++){if(cks[i].checked){var id=cks[i].value;url+="id="+id+"&";}}*/};
</script>
</head><body><c:if test="${empty cs}">无客户信息</c:if><c:if test="${not empty cs}"><div align="center"><form action="${pageContext.request.contextPath}/simpleSelect" method="post"><select name="field"><option>请选择条件</option><option value="name">按姓名查询</option><option value="cellphone">按手机号查询</option><option value="description">按描述查询</option></select><input type="text" name="msg"><input type="submit" value="查询"></form></div><br><form action="${pageContext.request.contextPath}/delSelect" method="post" id="f"><table border="1" align="center" width="85%"><tr><td><input type="checkbox" id="main" οnclick="change();"></td><td>客户编号</td><td>客户姓名</td><td>客户性别</td><td>客户生日</td><td>客户电话</td><td>客户邮箱</td><td>客户爱好</td><td>客户类型</td><td>客户备注</td><td>操作</td></tr><c:forEach items="${cs}" var="c"><tr><td><input type="checkbox" value="${c.id}" name="ck"></td><td>${c.id }</td><td>${c.name}</td><td>${c.gender }</td><td>${c.birthday }</td><td>${c.cellphone }</td><td>${c.email }</td><td>${c.preference }</td><td>${c.type }</td><td>${c.description }</td><td><ahref="${pageContext.request.contextPath}/findById?id=${c.id}">编辑</a><a href="javascript:void(0)" οnclick="del('${c.id}')">删除</a></td></tr></c:forEach><tr><td colspan="10"><a href="javascript:void(0)" οnclick="sendDel();">删除选中</a></td><td><a href="${pageContext.request.contextPath}/add.jsp">添加</a></td></tr></table></form></c:if></body>
</html>

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%><%@taglib prefix="my" uri="http://www.itcast.cn/tag"%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head><title>My JSP 'index.jsp' starting page</title><script type="text/javascript">function changeCurrentPage(value) {location.href = "/day20_1/findAllByPage?currentPage=" + value;};
</script>
</head><body><c:if test="${empty pb.cs}">无客户信息</c:if><c:if test="${not empty pb.cs}"><table border="1" align="center" width="85%"><tr><td>客户编号</td><td>客户姓名</td><td>客户性别</td><td>客户生日</td><td>客户电话</td><td>客户邮箱</td><td>客户爱好</td><td>客户类型</td><td>客户备注</td></tr><c:forEach items="${pb.cs}" var="c"><tr><td>${c.id }</td><td>${c.name}</td><td>${c.gender }</td><td>${c.birthday }</td><td>${c.cellphone }</td><td>${c.email }</td><td>${c.preference }</td><td>${c.type }</td><td>${c.description }</td></tr></c:forEach><tr><td colspan="9" align="center"><ahref="/day20_1/findAllByPage?pageNum=1¤tPage=${pb.currentPage}">首页</a>   <c:if test="${pb.pageNum==1}">上一页   </c:if> <c:if test="${pb.pageNum!=1}"><ahref="/day20_1/findAllByPage?pageNum=${pb.pageNum-1}¤tPage=${pb.currentPage}">上一页</a>   </c:if> <c:if test="${pb.pageNum==pb.totalPage}">下一页   </c:if> <c:if test="${pb.pageNum!=pb.totalPage}"><ahref="/day20_1/findAllByPage?pageNum=${pb.pageNum+1 }¤tPage=${pb.currentPage}">下一页</a>   </c:if> <ahref="/day20_1/findAllByPage?pageNum=${pb.totalPage }¤tPage=${pb.currentPage}">尾页</a>   <select name="currentPage"οnchange="changeCurrentPage(this.value);"><option>--请选择每页条数--</option><option value="5">5</option><option value="10">10</option><option value="20">20</option></select></td></tr><tr><td colspan="9" align="center"><c:forEach begin="1"end="${pb.totalPage}" var="n" step="1"><c:if test="${n==pb.pageNum}"><ahref="/day20_1/findAllByPage?pageNum=${n}¤tPage=${pb.currentPage}"><fontcolor='red'>第${n}页</font> </a>  </c:if><c:if test="${n!=pb.pageNum}"><ahref="/day20_1/findAllByPage?pageNum=${n}¤tPage=${pb.currentPage}">第${n}页</a>  </c:if></c:forEach></td></tr><tr><td colspan="9" align="center"><my:page pb="${pb}" /></td></tr></table></c:if></body>
</html>

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html><head><title>My JSP 'index.jsp' starting page</title></head><body><a href="${pageContext.request.contextPath}/findAll">查看所有客户信息</a><br><a href="${pageContext.request.contextPath}/findAllByPage">查看所有客户信息(分页展示)</a><br></body>
</html>

监听器（Listener）

• 监听三个域对象创建和销毁的事件监听器。
• 监听域对象中属性的增加和删除的事件监听器。
• 监听绑定到HttpSession域中的某个对象状态的事件监听器。

监听ServletContext域对象创建和销毁

编写Servlet监听器

package cn.itcast.web.listener.application;import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;public class MyServletContextListener implements ServletContextListener {@Overridepublic void contextDestroyed(ServletContextEvent arg0) {System.out.println("servletContext对象销毁");}@Overridepublic void contextInitialized(ServletContextEvent arg0) {System.out.println("servletContext对象创建");}}

<listener><listener-class>cn.itcast.web.listener.application.MyServletContextListener</listener-class>
</listener>

• 创建一个Session时，sessionCreated(HttpSessionEvent se) 方法将会被调用。
• 销毁一个Session时，sessionDestroyed (HttpSessionEvent se) 方法将会被调用。

监听HttpRequest域对象创建和销毁

监听三个域对象的属性变化

attributeAdded方法

attributeRemoved 方法

attributeReplaced 方法

演示web中监听器的使用：

package cn.itcast.web.listener.session;import javax.servlet.http.HttpSessionEvent;
import javax.servlet.http.HttpSessionListener;public class MySessionListener implements HttpSessionListener {@Overridepublic void sessionCreated(HttpSessionEvent arg0) {System.out.println("session对象创建了");}@Overridepublic void sessionDestroyed(HttpSessionEvent arg0) {System.out.println("session对象销毁了");}}

package cn.itcast.web.listener.session;import javax.servlet.http.HttpSessionAttributeListener;
import javax.servlet.http.HttpSessionBindingEvent;public class MySessionAttributeListener implements HttpSessionAttributeListener {@Overridepublic void attributeAdded(HttpSessionBindingEvent arg0) {// arg0.getSession(); 获取事件源，也就是获取session对象System.out.println(arg0.getName());System.out.println(arg0.getValue());System.out.println("向session中添加属性");}@Overridepublic void attributeRemoved(HttpSessionBindingEvent arg0) {System.out.println("从session中移除属性");}@Overridepublic void attributeReplaced(HttpSessionBindingEvent arg0) {System.out.println("将session中的属性修改");}}

<listener><listener-class>cn.itcast.web.listener.session.MySessionListener</listener-class></listener><listener><listener-class>cn.itcast.web.listener.session.MySessionAttributeListener</listener-class></listener>

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>My JSP 'session.jsp' starting page</title></head><body><%session.setAttribute("sname", "svalue"); //添加session.setAttribute("sname", "sssss"); //修改session.removeAttribute("sname"); //移除session.invalidate();%>
</body>
</html>

package cn.itcast.web.listener.request;import javax.servlet.ServletRequestEvent;
import javax.servlet.ServletRequestListener;public class MyRequestListener implements ServletRequestListener {@Overridepublic void requestDestroyed(ServletRequestEvent arg0) {System.out.println("request对象销毁");}@Overridepublic void requestInitialized(ServletRequestEvent arg0) {System.out.println("request对象创建");}}

<listener><listener-class>cn.itcast.web.listener.request.MyRequestListener</listener-class>
</listener>

Session绑定JavaBean的事件监听器

HttpSessionBindingListener接口:

• 实现了HttpSessionBindingListener接口的 JavaBean 对象可以感知自己被绑定到 Session 中和从 Session 中删除的事件
• 当对象被绑定到 HttpSession 对象中时，web 服务器调用该对象的  void valueBound(HttpSessionBindingEvent event) 方法
• 当对象从 HttpSession 对象中解除绑定时，web 服务器调用该对象的 void valueUnbound(HttpSessionBindingEvent event)方法

HttpSessionActivationListener接口

• 实现了HttpSessionActivationListener接口的 JavaBean 对象可以感知自己被活化和钝化的事件
• 当绑定到 HttpSession 对象中的对象将要随 HttpSession 对象被钝化之前，web 服务器调用如下方法sessionWillPassivate(HttpSessionBindingEvent event) 方法
• 当绑定到 HttpSession 对象中的对象将要随 HttpSession 对象被活化之后，web 服务器调用该对象的 void sessionDidActive(HttpSessionBindingEvent event)方法

<Context>
<Manager className="org.apache.catalina.session.PersistentManager" maxIdleSwap="1">
<Store className="org.apache.catalina.session.FileStore" directory="it315"/>
</Manager>
</Context>

package cn.itcast.web.listener.domain;import javax.servlet.http.HttpSessionActivationListener;
import javax.servlet.http.HttpSessionBindingEvent;
import javax.servlet.http.HttpSessionBindingListener;
import javax.servlet.http.HttpSessionEvent;public class User implements HttpSessionBindingListener,HttpSessionActivationListener {private int id;private String name;public int getId() {return id;}public void setId(int id) {this.id = id;}public String getName() {return name;}public void setName(String name) {this.name = name;}@Overridepublic void sessionDidActivate(HttpSessionEvent arg0) {System.out.println("活化");}@Overridepublic void sessionWillPassivate(HttpSessionEvent arg0) {System.out.println("钝化");}@Overridepublic void valueBound(HttpSessionBindingEvent arg0) {System.out.println("将user对象绑定到了session中");}@Overridepublic void valueUnbound(HttpSessionBindingEvent arg0) {System.out.println("从session中将user对象移除");}}

<%@page import="cn.itcast.web.listener.domain.User"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head><title>My JSP 'index.jsp' starting page</title></head><body><%User user = new User();user.setId(1);user.setName("tom");session.setAttribute("user", user); //绑定%>
</body>
</html>

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@ page import="cn.itcast.web.listener.domain.*" %><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head><title>My JSP 'index.jsp' starting page</title></head><body><%session.removeAttribute("user");//移除%>
</body>
</html>

<%@page import="cn.itcast.web.listener.domain.*"%>
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head><title>My JSP 'index.jsp' starting page</title></head><body>${user.name}
</body>
</html>

监听器案例（销毁长时间不适用的Session）

package cn.itcast.listener.demo;import java.util.ArrayList;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.Timer;
import java.util.TimerTask;import javax.servlet.ServletContext;
import javax.servlet.ServletContextEvent;
import javax.servlet.ServletContextListener;
import javax.servlet.http.HttpSession;public class MyServletContextListener implements ServletContextListener {private List<HttpSession> sessions = Collections.synchronizedList(new ArrayList<HttpSession>());// 线程安全的List集合.public void contextDestroyed(ServletContextEvent sce) {}public void contextInitialized(ServletContextEvent sce) {// 这个方法执行了，就说明项目启动了.// 1.得到ServletContext对象ServletContext context = sce.getServletContext();// 2,将集合保存到context中.context.setAttribute("sessions", sessions);// 3.开始扫描Timer t = new Timer();t.schedule(new TimerTask() {@Overridepublic void run() {System.out.println("开始扫描session");// 判断session是否过期.----session如果10秒钟没有使用，将其销毁.for (Iterator<HttpSession> it = sessions.iterator(); it.hasNext();) {HttpSession session = it.next();// 判断session是否过期if (System.currentTimeMillis()- session.getLastAccessedTime() > 10000) {System.out.println(session.getId() + " 已经超时，被销毁了。");// sessions.remove(session);// 从集合中删除it.remove();session.invalidate();// 销毁session}}}}, 1000, 3000);}}

package cn.itcast.listener.demo;import java.util.List;import javax.servlet.ServletContext;
import javax.servlet.http.HttpSession;
import javax.servlet.http.HttpSessionEvent;
import javax.servlet.http.HttpSessionListener;//用于监听session对象创建，如果创建了，将其保存到一个集合中。
public class MyHttpSessionListener implements HttpSessionListener {public void sessionCreated(HttpSessionEvent se) {// session创建了.// 1.得到sessionHttpSession session = se.getSession();// 2.将session保存到集合中.// 集合是在ServletContext中存储的，我们只需要从ServletContext中获取就可以。ServletContext context = session.getServletContext();List<HttpSession> sessions = (List<HttpSession>) context.getAttribute("sessions");sessions.add(session);System.out.println(session.getId() + " 添加到了集合");}public void sessionDestroyed(HttpSessionEvent se) {// TODO Auto-generated method stub}}

<!-- 监听器案例--><listener><listener-class>cn.itcast.listener.demo.MyServletContextListener</listener-class></listener><listener><listener-class>cn.itcast.listener.demo.MyHttpSessionListener</listener-class></listener>