首先看一下项目结构

第一步先导入jar包

pom.xml

   <properties>
            <spring.version>4.3.18.RELEASE</spring.version>
        </properties>
        <dependencies>
            <!--spring的核心的jar包-->
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-core</artifactId>
                <version>${spring.version}</version>
            </dependency>
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-beans</artifactId>
                <version>${spring.version}</version>
            </dependency>
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-context</artifactId>
                <version>${spring.version}</version>
            </dependency>
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-tx</artifactId>
                <version>${spring.version}</version>
            </dependency>
            <!--spring mvc的jar包-->
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-web</artifactId>
                <version>${spring.version}</version>
            </dependency>
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-webmvc</artifactId>
                <version>${spring.version}</version>
            </dependency>
            <!--spring jdbc的jar包-->
            <dependency>
                <groupId>org.springframework</groupId>
                <artifactId>spring-jdbc</artifactId>
                <version>${spring.version}</version>
            </dependency>
            <!--mybatis的jar包-->
            <dependency>
                <groupId>org.mybatis</groupId>
                <artifactId>mybatis</artifactId>
                <version>3.4.6</version>
            </dependency>
            <!--spring 和mybatis整合的中间件jar包-->
            <dependency>
                <groupId>org.mybatis</groupId>
                <artifactId>mybatis-spring</artifactId>
                <version>1.3.2</version>
            </dependency>
            <!--orace的驱动包-->
            <dependency>
                <groupId>com.oracle</groupId>
                <artifactId>oracle6</artifactId>
                <version>6</version>
            </dependency>
            <!--spring 实现文件上传的jar包-->
            <dependency>
                <groupId>commons-io</groupId>
                <artifactId>commons-io</artifactId>
                <version>1.3.2</version>
            </dependency>
            <dependency>
                <groupId>commons-fileupload</groupId>
                <artifactId>commons-fileupload</artifactId>
                <version>1.2.1</version>
            </dependency>
            <!--解析json数据的jar包-->
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-core</artifactId>
                <version>2.9.8</version>
            </dependency>
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-annotations</artifactId>
                <version>2.9.8</version>
            </dependency>
            <dependency>
                <groupId>com.fasterxml.jackson.core</groupId>
                <artifactId>jackson-databind</artifactId>
                <version>2.9.8</version>
            </dependency>
            <!--数据库连接池的jar包-->
            <dependency>
                <groupId>commons-dbcp</groupId>
                <artifactId>commons-dbcp</artifactId>
                <version>1.4</version>
            </dependency>
            <!--jstl的jar包-->
            <dependency>
                <groupId>jstl</groupId>
                <artifactId>jstl</artifactId>
                <version>1.2</version>
            </dependency>
            <!--j2ee的jar包-->
            <dependency>
                <groupId>javax.servlet</groupId>
                <artifactId>servlet-api</artifactId>
                <version>2.5</version>
                <scope>provided</scope>
            </dependency>
        </dependencies>
        <build>
            <resources>
                <!--指定src main java下所有的目录下的xml文件都编译-->
                <resource>
                    <directory>src/main/java</directory>
                    <includes>
                        <include>**/*.xml</include>
                    </includes>
                </resource>
            </resources>
        </build>

导入jar包之后下载到本地仓库,这里Oracle的jar包是下载不了的,需要自己下载引入到本地仓库才可以使用

直接window+r回车输入mvn install:install-file -Dfile=jar包的位置+jar包名 -DgroupId=上面的groupId(自定义) -DartifactId=上面的artifactId(自定义) -Dversion=版本号 -Dpackaging=jar

例mvn install:install-file -Dfile=D:\jar包\ojdbc6\ojdbc6.jar -DgroupId=com.oracle -DartifactId=oracle6 -Dversion=6 -Dpackaging=jar

第二步:创建dao层

EmpDao.java

package com.aaa.ssm.dao;

import com.aaa.ssm.entity.Emp;

import java.util.*;

public interface EmpDao {
    /**
     * 查询所有员工信息
     * @return
     */
    public List<Emp> findAllEmp();

    /**
     * 根据ID删除员工信息
     * @param empno
     * @return
     */
    public int deleteEmp(int empno);

    /**
     * 根据ID查询要修改的员工信息
     * @param empno
     * @return
     */
    public List<Emp> toUpdate(int empno);

    /**
     * 添加员工信息
     * @param emp
     * @return
     */
    public int insertEmp(Emp emp);

    /**
     * 修改员工信息
     * @param emp
     * @return
     */
    public int updateEmp(Emp emp);
}

EmpDaoMapper.xml

<!DOCTYPE mapper PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.aaa.ssm.dao.EmpDao">

    <select id="findAllEmp" resultType="com.aaa.ssm.entity.Emp">
        select * from emp
    </select>
    <delete id="deleteEmp" parameterType="int">
        delete from emp where empno=#{empno}
    </delete>
    <select id="toUpdate" resultType="com.aaa.ssm.entity.Emp">
        select * from emp where empno=#{empno}
    </select>

    <insert id="insertEmp">
        <selectKey resultType="int" keyProperty="empno" order="BEFORE">
            select seq_emp.nextval from dual
        </selectKey>
        insert into emp(empno,ename,job,mgr,sal,comm,deptno) VALUES(#{empno},#{ename},#{job},#{mgr},#{sal},#{comm},#{deptno})
    </insert>
    <update id="updateEmp">
        update emp set ename=#{ename},job=#{job},mgr=#{mgr},sal=#{sal},comm=#{comm},deptno=#{deptno} where empno=#{empno}
    </update>
</mapper>

第三步:创建service层

EmpService.java接口

package com.aaa.ssm.service;

import com.aaa.ssm.entity.Emp;

import java.util.*;

public interface EmpService {
    /**
     * 查询所有员工信息
     * @return
     */
    public List<Emp> findAllEmp();

    /**
     * 根据ID删除员工信息
     * @param empno
     * @return
     */
    public int deleteEmp(int empno);

    /**
     * 根据ID查询要修改的员工信息
     * @param empno
     * @return
     */
    public List<Emp> toUpdate(int empno);
    /**
     * 添加员工信息
     * @param emp
     * @return
     */
    public int insertEmp(Emp emp);
    /**
     * 修改员工信息
     * @param emp
     * @return
     */
    public int updateEmp(Emp emp);
}

EmpServiceImpl.java实现类

package com.aaa.ssm.service.impl;

import com.aaa.ssm.dao.EmpDao;
import com.aaa.ssm.entity.Emp;
import com.aaa.ssm.service.EmpService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.transaction.annotation.Transactional;

import java.util.List;
@Service
@Transactional
public class EmpDaoImpl implements EmpService {
    @Autowired
    private EmpDao dao;

    public List<Emp> findAllEmp() {
        return  dao.findAllEmp();
    }

    public int deleteEmp(int empno) {
        return dao.deleteEmp(empno);
    }

    public List<Emp> toUpdate(int empno) {
        return  dao.toUpdate(empno);
    }

    public int insertEmp(Emp emp) {
        return dao.insertEmp(emp);
    }

    public int updateEmp(Emp emp) {
        return dao.updateEmp(emp);
    }
}

第四步:创建实体

Emp.java

package com.aaa.ssm.entity;

public class Emp {
    private Integer empno;
    private String ename;
    private String job;
    private Integer mgr;
    private String hiredate;
    private Double sal;
    private Integer comm;
    private Integer deptno;

    public Integer getEmpno() {
        return empno;
    }

    public void setEmpno(Integer empno) {
        this.empno = empno;
    }

    public String getEname() {
        return ename;
    }

    public void setEname(String ename) {
        this.ename = ename;
    }

    public String getJob() {
        return job;
    }

    public void setJob(String job) {
        this.job = job;
    }

    public Integer getMgr() {
        return mgr;
    }

    public void setMgr(Integer mgr) {
        this.mgr = mgr;
    }

    public String getHiredate() {
        return hiredate;
    }

    public void setHiredate(String hiredate) {
        this.hiredate = hiredate;
    }

    public Double getSal() {
        return sal;
    }

    public void setSal(Double sal) {
        this.sal = sal;
    }

    public Integer getComm() {
        return comm;
    }

    public void setComm(Integer comm) {
        this.comm = comm;
    }

    public Integer getDeptno() {
        return deptno;
    }

    public void setDeptno(Integer deptno) {
        this.deptno = deptno;
    }
}

第五步:创建controller层

EmpController.java

package com.aaa.ssm.controller;

import com.aaa.ssm.entity.Emp;
import com.aaa.ssm.service.EmpService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.RequestMapping;

import java.util.List;

@Controller
@RequestMapping("/emp")
public class EmpController {
    @Autowired
    private EmpService ser;
    @RequestMapping("/findallemp")
    public String findAllEmp(Model model){
        List<Emp> list = ser.findAllEmp();
        model.addAttribute("list",list);
        return "allemp";
    }
    @RequestMapping("/deleteemp")
    public String deleteEmp(int empno){
        ser.deleteEmp(empno);
        return "redirect:/emp/findallemp.do";
    }
    @RequestMapping("/toupdate")
    public String toUpdate(Integer empno,Model model){
        if(empno!=null){
            List<Emp> list = ser.toUpdate(empno);
            model.addAttribute("emp",list.get(0));
        }
        return "ioru";
    }
    @RequestMapping("/insertorupdateemp")
    public String InsertOrUpdateEmp(Emp emp){
        if (emp.getEmpno()!=null){
            ser.updateEmp(emp);
        }else{
            ser.insertEmp(emp);
        }
        return "redirect:/emp/findallemp.do";
    }
}

第六步:创建配置文件

spring.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context" xmlns:tx="http://www.springframework.org/schema/tx"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx.xsd">
    <!--第一步,扫描service -->
        <context:component-scan base-package="com.aaa.ssm.service.impl"></context:component-scan>
        <!--第二步,加载jdbc.properties-->
        <context:property-placeholder location="classpath:jdbc.properties"></context:property-placeholder>
        <bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource">
            <property name="driverClassName" value="${driver}"></property>
            <property name="url" value="${url}"></property>
            <property name="username" value="${user}"></property>
            <property name="password" value="${password}"></property>
        </bean>
        <!--第四步,创建mybatis的工厂类对象-->
        <bean class="org.mybatis.spring.SqlSessionFactoryBean">
            <!--指定数据源-->
            <property name="dataSource" ref="dataSource"></property>
            <!--加载mybatis的映射文件 在value中可以使用*号通配符-->
            <property name="mapperLocations" value="classpath:com/aaa/ssm/dao/*.xml"></property>
            <!--加载mybatis中的配置文件-->
            <property name="configLocation" value="classpath:mybatis.xml"></property>
        </bean>
        <!--第五步,在spring 的工厂中生成dao接口的实现类对象 -->
        <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
            <!--指定要扫描哪个包下面所有的dao接口-->
            <property name="basePackage" value="com.aaa.ssm.dao"></property>
        </bean>
        <!--第六步,创建spring的事物管理器-->
        <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
            <property name="dataSource" ref="dataSource"></property>
        </bean>
        <!--第七步,声明以注解的方式配置声明式事物-->
        <tx:annotation-driven transaction-manager="transactionManager" ></tx:annotation-driven>
</beans>

spring-mvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd">
     <!--第一步,扫描控制器包-->
         <context:component-scan base-package="com.aaa.ssm.controller"></context:component-scan>
         <!--第二步,声明以注解的方式使用spring mvc-->
         <mvc:annotation-driven></mvc:annotation-driven>
         <!--第三步,配置spring mvc 内置的视图解析器-->
         <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
             <property name="prefix" value="/WEB-INF/jsp/"></property>
             <property name="suffix" value=".jsp"></property>
         </bean>
</beans>

mybatis.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <settings>
        <!--打印日志可以看执行的sql语句-->
        <setting name="logImpl" value="STDOUT_LOGGING"/>
    </settings>
</configuration>

jdbc.properties

driver=oracle.jdbc.driver.OracleDriver
url=jdbc:oracle:thin:@localhost:1521:orcl
user=scott
password=tiger

web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_3_1.xsd"
         version="3.1">
     <listener>
             <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
         </listener>
         <context-param>
             <param-name>contextConfigLocation</param-name>
             <param-value>classpath:spring.xml</param-value>
         </context-param>
         <servlet>
             <servlet-name>spring-mvc</servlet-name>
             <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
             <init-param>
                 <param-name>contextConfigLocation</param-name>
                 <param-value>classpath:spring-mvc.xml</param-value>
             </init-param>
         </servlet>
         <servlet-mapping>
             <servlet-name>spring-mvc</servlet-name>
             <url-pattern>*.do</url-pattern>
         </servlet-mapping>
          <filter>
                 <filter-name>characterEncodingFilter</filter-name>
                 <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
                 <init-param>
                     <param-name>encoding</param-name>
                     <param-value>UTF-8</param-value>
                 </init-param>
                 <init-param>
                     <param-name>forceResponseEncoding</param-name>
                     <param-value>true</param-value>
                 </init-param>
             </filter>
         <filter-mapping>
             <filter-name>characterEncodingFilter</filter-name>
             <url-pattern>/*</url-pattern>
         </filter-mapping>
</web-app>

到这里后台代码就写完了,接下来是前台的界面

WEB-INF目录下新建一个jsp文件夹

这里如果新建的maven项目没有web目录那么这样添加

然后在jsp文件夹下创建jsp文件

allemp.jsp

<%--
  Created by IntelliJ IDEA.
  User: ASUS
  Date: 2019/6/3
  Time: 16:02
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%
    String path = request.getContextPath();
    String basePath = request.getScheme() + "://"
            + request.getServerName() + ":" + request.getServerPort()
            + path + "/";
%>
<html>
<head>
    <title>员工信息</title>
</head>
<body>
<table border="1">
    <tr>
        <th>员工编号</th>
        <th>员工姓名</th>
        <th>职位</th>
        <th>上级领导编号</th>
        <th>入职时间</th>
        <th>基本工资</th>
        <th>奖金</th>
        <th>部门编号</th>
        <th>操作</th>
    </tr>
    <c:forEach items="${list}" var="m">
    <tr>
        <td>${m.empno}</td>
        <td>${m.ename}</td>
        <td>${m.job}</td>
        <td>${m.mgr}</td>
        <td>${m.hiredate}</td>
        <td>${m.sal}</td>
        <td>${m.comm}</td>
        <td>${m.deptno}</td>
        <td>
            <a href="<%=path%>/emp/deleteemp.do?empno=${m.empno}">删除</a>
            <a href="<%=path%>/emp/toupdate.do?empno=${m.empno}">修改</a>
        </td>
    </tr>
    </c:forEach>
    <a href="<%=path%>/emp/toupdate.do">添加</a>
</body>
</html>

ioru.xml

<%--
  Created by IntelliJ IDEA.
  User: ASUS
  Date: 2019/6/3
  Time: 16:57
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>
<form method="post" action="/emp/insertorupdateemp.do">
    <input type="hidden" value="${emp.empno}" name="empno" >
    员工姓名:<input type="text" name="ename" value="${emp.ename}" ><br/>
    员工职位:<input type="text" name="job" value="${emp.job}" ><br/>
    员工上级领导:<input type="text" name="mgr" value="${emp.mgr}" ><br/>
    员工基本工资:<input type="text" name="sal" value="${emp.sal}" ><br/>
    员工奖金:<input type="text" name="comm" value="${emp.comm}" ><br/>
    部门编号:<input type="text" name="deptno" value="${emp.deptno}" ><br/>
    <input type="submit" value="保存">
</form>
</body>
</html>

到这来就结束了。测试一下查询