学校网站建设工作方案,昆明做网站词排名优化,wap网站开发教材,管理培训一 思路
1 组件 页面显示#xff1a;JSP 接受用户请求#xff1a;Servlet 和数据库交互#xff1a;MyBatis
2 基础准备
① 创建 web 项目#xff0c;导入需要依赖的 jar 包,放入 web/WEB-INF/lib目录中 ② 创建数据库表
CREATE TABLE employee(
id bigint(11)…一 思路
1 组件 页面显示JSP 接受用户请求Servlet 和数据库交互MyBatis
2 基础准备
① 创建 web 项目导入需要依赖的 jar 包,放入 web/WEB-INF/lib目录中 ② 创建数据库表
CREATE TABLE employee(
id bigint(11) NOT NULL auto_increment,name varchar(50) default NULL,salary double(10,2) default NULL,PRIMARY KEY (id)
);INSERT INTO employee VALUES (1,大黄, 8848.00);
INSERT INTO employee VALUES (2,a黄, 8848.00);
INSERT INTO employee VALUES (3,b黄, 8848.00);
INSERT INTO employee VALUES (4,c黄, 8848.00);
INSERT INTO employee VALUES (5,d黄, 8848.00);
INSERT INTO employee VALUES (6,e黄, 8848.00);
INSERT INTO employee VALUES (7,f黄, 8848.00);
INSERT INTO employee VALUES (8,g黄, 8848.00);
INSERT INTO employee VALUES (9,h黄, 8848.00);③ 创建表对应的实体类
Data
AllArgsConstructor
NoArgsConstructor
public class Employee {private Long id;private String name;private double salary;
}④ MyBatis 配置文件实现
db.properties
jdbc.drivercom.mysql.jdbc.Driver
jdbc.urljdbc:mysql:///play_web
jdbc.userroot
jdbc.passwordrootmybatis-config.xml
?xml version1.0 encodingUTF-8 ?
!DOCTYPE configurationPUBLIC -//mybatis.org//DTD Config 3.0//ENhttp://mybatis.org/dtd/mybatis-3-config.dtd
configurationproperties resourcedb.properties/propertiestypeAliasespackage namecom.domain//typeAliasesenvironments defaultdevenvironment iddevtransactionManager typeJDBC/transactionManagerdataSource typePOOLEDproperty namedriver value${jdbc.driver}/property nameurl value${jdbc.url}/property nameusername value${jdbc.user}/property namepassword value${jdbc.password}//dataSource/environment/environmentsmappersmapper resourcemappers/EmployeeMapper.xml/mapper/mappers
/configuration⑤ 抽取工具类
MybatisUtil
package com.util;
public class MybatisUtil {private static SqlSessionFactory factorynull;static {try {InputStream rs Resources.getResourceAsStream(mybatis-config.xml);factory new SqlSessionFactoryBuilder().build(rs);} catch (IOException e) {e.printStackTrace();}}public static SqlSession getSqlSession(){return factory.openSession(true);}
}StringUtil – 判空
public class StringUtil {//判断输入的表单参数是否为空public static boolean hasLength(String s){return s!null s.trim().length()!0;
}}⑥ 根据实体类创建 dao 包以及接口
Dao
package com.dao;
import com.domain.Employee;
import java.util.List;
public interface EmployeeDao {// 增int add(Employee employee);// 删int delete(Long id);// 改int update(Employee employee);// 查全部ListEmployee list();// 根据id查Employee queryOne(Long id);
}impl
package com.dao.impl;
import com.dao.EmployeeDao;
import com.domain.Employee;
import com.util.MybatisUtil;
import org.apache.ibatis.session.SqlSession;
import java.util.List;
public class EmployeeDaoImpl implements EmployeeDao {/*定义成员变量*/private SqlSession sqlSession MybatisUtil.getSqlSession();Overridepublic int add(Employee employee) {int row sqlSession.insert(com.mapper.EmployeeMapper.add, employee);return row;}Overridepublic int delete(Long id) {int row sqlSession.delete(com.mapper.EmployeeMapper.delete,id);return row;}Overridepublic int update(Employee employee) {int row sqlSession.update(com.mapper.EmployeeMapper.update,employee);return row;}Overridepublic ListEmployee list() {ListEmployee list sqlSession.selectList(com.mapper.EmployeeMapper.list);return list;}Overridepublic Employee queryOne(Long id) {Employee employee sqlSession.selectOne(com.mapper.EmployeeMapper.selectOne, id);return employee;}
}mapper
?xml version1.0 encodingUTF-8 ?
!DOCTYPE mapperPUBLIC -//mybatis.org//DTD Mapper 3.0//ENhttp://mybatis.org/dtd/mybatis-3-mapper.dtd
mapper namespacecom.mapper.EmployeeMapper!--增加商品--insert idaddinsert into employee (name,salary)values(#{name},#{salary})/insert!--修改--update idupdateupdate employee set name#{name},salary#{salary} WHERE id#{id}/update!--删除--delete iddeletedelete from employee WHERE id#{id}/delete!--根据id查询--select idqueryOne resultTypeemployeeSELECT * from employee WHERE id#{id}/select!--查询所有--select idlist resultTypeemployeeSELECT * from employee/select
/mapper⑦ 日志文件 – log4j.properties
# Global logging configuration
log4j.rootLoggerERROR, stdout
# MyBatis logging configuration...
log4j.logger.com.domainTRACE
# Console output...
log4j.appender.stdoutorg.apache.log4j.ConsoleAppender
log4j.appender.stdout.layoutorg.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern%5p [%t] - %m%n⑧ 生成测试类 EmployeeDaoImplTest查看后台功能是否实现
package com.dao.impl;
import com.dao.EmployeeDao;
import com.domain.Employee;
import org.junit.Test;
import java.util.List;
public class EmployeeDaoImplTest {Testpublic void add() {}Testpublic void delete() {}Testpublic void update() {}Testpublic void list() {EmployeeDao employeeDaonew EmployeeDaoImpl();ListEmployee list employeeDao.list();System.out.println(list);}Testpublic void queryOne() {}
}二 前台实现
1 请求分发器 使用一个 Servlet 类来处理一张表的所有请求操作即通过增加一个参数用参数值来区分一个Servlet 中来区分不同的操作crud
package com.web.servlet;import com.dao.EmployeeDao;
import com.dao.impl.EmployeeDaoImpl;
import com.domain.Employee;
import com.util.StringUtil;import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.util.List;WebServlet(/employee)
public class EmployeeServlet extends HttpServlet {// 创建Dao对象private EmployeeDao employeeDaonew EmployeeDaoImpl();Overrideprotected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {// 设置编码格式req.setCharacterEncoding(utf-8);resp.setContentType(text/html;charsetutf-8);// 获取请求分发的参数String cmdreq.getParameter(cmd);if(delete.equals(cmd)){// 调用删除delete(req,resp);}else if(input.equals(cmd)){// 跳转增加input(req,resp);}else if(saveOrUpdate.equals(cmd)){// 跳转修改saveOrUpdate(req,resp);}else {// 查所有list(req,resp);}}/*查询所有*/private void list(HttpServletRequest req, HttpServletResponse resp) {try {// 调用Dao查所有方法ListEmployee listemployeeDao.list();// 将查询结果存储到请求作用域req.setAttribute(list,list);// 转发到列表页面req.getRequestDispatcher(/WEB-INF/views/employee/list.jsp).forward(req,resp);} catch (ServletException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}}/*增加修改保存*/private void saveOrUpdate(HttpServletRequest req, HttpServletResponse resp) {//封装员工对象Employee employeenew Employee();/*将参数的获取及封装对象过程抽取成一个方法*/req2employee(req,employee);/*根据请求中是否携带id判断执行增加或者修改操作*/String id req.getParameter(id);if (StringUtil.hasLength(id)){employee.setId(Long.valueOf(id));//执行修改employeeDao.update(employee);}else{//调用dao方法执行增加保存操作employeeDao.add(employee);}try {//跳转到查询resp.sendRedirect(/employee);} catch (IOException e) {e.printStackTrace();}}/*封装的获取请求参数的方法*/private void req2employee(HttpServletRequest req, Employee employee) {//获取请求中表单参数String name req.getParameter(name);//验证输入的表单参数不能为空if (StringUtil.hasLength(name)){//设置员工的名称employee.setName(name);}String salary req.getParameter(salary);if (StringUtil.hasLength(salary)){employee.setSalary(Double.valueOf(salary));}}/*跳转到编辑页面*/private void input(HttpServletRequest req, HttpServletResponse resp) {//根据请求中是否携带id判断是增加或者修改操作String id req.getParameter(id);if (StringUtil.hasLength(id)){//请求中携带了id执行修改//根据id查询商品Employee employee employeeDao.queryOne(Long.valueOf(id));//将查询的商品存储到作用域req.setAttribute(employee,employee);}try {//跳转到WEB-INF下面的页面input.jspreq.getRequestDispatcher(/WEB-INF/views/employee/input.jsp).forward(req,resp);} catch (Exception e) {e.printStackTrace();}}/*删除*/private void delete(HttpServletRequest req, HttpServletResponse resp) {try {//获取目标idString id req.getParameter(id);//调用删除方法int row employeeDao.delete(Long.valueOf(id));//删除完毕跳转到查询resp.sendRedirect(/employee);} catch (IOException e) {e.printStackTrace();}}
}2 前端crud实现
① input.jsp
% page contentTypetext/html;charsetUTF-8 languagejava %
%taglib prefixc urihttp://java.sun.com/jsp/jstl/core %
html
headtitle员工信息编辑页面/title
/head
body
h3员工信息编辑/h3
form action/employee?cmdsaveOrUpdate methodpostinput typehidden nameid value${employee.id}p姓名input typetext namename value${employee.name}/p%--step0.01表示接受小数点后两位--%p工资input typenumber step0.01 namesalary value${employee.salary}/ppinput typesubmit value保存/p
/form
/body
/html
② list.jsp
% page contentTypetext/html;charsetUTF-8 languagejava %
%--引入核心标签库--%
%taglib prefixc urihttp://java.sun.com/jsp/jstl/core %
html
headtitle员工信息页面/title
/head
body
centerh3员工列表/h3pa href/employee?cmdinput增加员工/a/ptable border1px cellpadding0 cellspacing0width800pxtrth序号/thth姓名/thth工资/thth操作/th/tr%--动态展示商品列表数据--%c:forEach items${list} varStatusvs varemployeetr classtrClasstd${vs.count}/tdtd${employee.name}/tdtd${employee.salary}/tdtda href/employee?cmdinputid${employee.id}修改员工信息/anbsp;nbsp;
%-- a href/product?cmddeleteid${product.id}删除商品/a--%a href# onclickdeleteTr(${employee.id})删除员工信息/a/td/tr/c:forEach/table
/center%--鼠标移动到当前行实现背景颜色高亮显示--%
script//获取所有的行元素不包含表头var trs document.getElementsByClassName(trClass);//遍历行元素集合for(var i0;itrs.length;i){//鼠标移入当前行高亮背景变成灰色trs[i].onmouseoverfunction (){this.style.backgroundColorgray;}//鼠标移出恢复原来背景颜色trs[i].onmouseoutfunction (){this.style.backgroundColor;}}
/script%--删除确认表--%
scriptfunction deleteTr(id){//确认删除var b window.confirm(确认删除选中的员工信息吗);if(b){//确定删除执行后台删除操作window.location/employee?cmddeleteidid;}}
/script
/body
/html③ index.jsp
% page contentTypetext/html;charsetUTF-8 languagejava %
htmlheadtitle员工信息管理/title/headbodya href/employee员工信息管理/a/body
/html三 小结
1 目录结构图 2 注意 不需要数据共享的跳转直接使用重定向即可
