SSM+Maven+IDEA增删改查

开发工具

IntelliJ IDEA
Apache-tomcat-9.0
JDK 1.8
MySQL 8.0.11
Maven 3.5.4

IDEA+Maven搭建项目骨架

1. 新建Maven项目：
点击File -> New -> Project -> Maven -> 勾选 Create from archetype -> 选择 maven-archetype-webapp (注意：此处不要错选成上面的cocoom-22-archetype-webapp)

在弹出的new project 选项卡中填写GroupId和Artifactid，其中GroupID是项目组织唯一的标识符，实际对应JAVA的包的结构，是main目录里java的目录结构，ArtifactID是项目的唯一的标识符，实际对应项目的名称，就是项目根目录的名称。对于入门练习，这两项可以随意填写。

之后点击next 选择Maven版本（其中IDEA 专业版自带Maven，也可以选择自己下载的maven）。之后填写项目名称和项目地址，完成后点击Finish，完成项目骨架的创建。

2. 在新建的项目中添加所需要的文件/文件夹

创建之后的项目如图所示，我们需要在这之上新建一些目录。

在项目的根目录下新建target文件夹，系统自动将其设置为“Excluded”

在src/main目录下新建Directory：“java”，并将其设置为“Source Root”（即：此项目默认的代码文件源目录）

在刚才新建的java文件下新建“com”包，再在com包下新建四个包，分别命名为：pojo,service,dao,controller。（如果出现下图中所示的包名重叠的情况，可以点击图中所示的图标，将“Hide empty middle package取消掉”）

上面新建的四个包：pojo,service,dao,controller，其所存放的分别是：

pojo: 存放自定义的java类。如：paper类，user类，book类等，每个类的属性设为private，并提供public属性的getter/setter方法让外界访问
service：定义接口，包含系统所提供的功能。（之后还会在service包下再新建impl包）。
dao：定义接口，包含与数据库进行交互的功能。
controller：控制器，负责接收页面请求，转发和处理。
在resource包下新建Directory：“mapper”（用于存放xxxMapper.xml文件）和“spring”（用于存放spring-xxx.xml配置文件），新建文件：“jdbc.properties”（mysql数据库配置文件）,”log4j.properties”（日志输出配置文件）,”mybatis-config.xml”（mybatis框架配置文件）。

在web-inf目录下新建“jsp”包，存放xxx.jsp显示界面。
补充之后的项目目录如下图所示，至此项目骨架搭建完毕，开始写代码实现增删改查功能

3. 自定义Paper类

在这之前要对项目的pom.xml文件进行配置，在此文件中配置项目所需要的jar包。

pom.xml

<?xml version="1.0" encoding="UTF-8"?>

<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
  xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
  <modelVersion>4.0.0</modelVersion>
  <groupId>com.tanlei</groupId>
  <artifactId>SSM</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>
  <name>SSM Maven Webapp</name>
  <!-- FIXME change it to the project's website -->
  <url>http://www.example.com</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
    <maven.compiler.source>1.7</maven.compiler.source>
    <maven.compiler.target>1.7</maven.compiler.target>
    <spring.version>5.0.3.RELEASE</spring.version>
    <mybatis.version>3.4.4</mybatis.version>
  </properties>

  <dependencies>
    <!-- 单元测试 -->
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>
    <!-- 第一部分：Spring 配置-->
    <!-- Spring core -->
    <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>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-context-support</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <!-- Spring DAO -->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-tx</artifactId>
      <version>${spring.version}</version>
    </dependency>

    <!-- Spring mvc -->
    <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>
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-test</artifactId>
      <version>${spring.version}</version>
    </dependency>
    <!-- 第二部分：Servlet web -->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>javax.servlet-api</artifactId>
      <version>3.0.1</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>javax.servlet.jsp</groupId>
      <artifactId>jsp-api</artifactId>
      <version>2.2</version>
      <scope>provided</scope>
    </dependency>
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>jstl</artifactId>
      <version>1.2</version>
    </dependency>
    <dependency>
      <groupId>taglibs</groupId>
      <artifactId>standard</artifactId>
      <version>1.1.2</version>
    </dependency>
    <dependency>
      <groupId>com.fasterxml.jackson.core</groupId>
      <artifactId>jackson-databind</artifactId>
      <version>2.9.4</version>
    </dependency>
    <!-- 第三部分：数据库和mybatis -->
    <!-- 数据库 -->
    <dependency>
      <groupId>mysql</groupId>
      <artifactId>mysql-connector-java</artifactId>
      <version>5.5.25</version>
    </dependency>
    <!-- 数据库连接池 -->
    <dependency>
      <groupId>com.mchange</groupId>
      <artifactId>c3p0</artifactId>
      <version>0.9.5.2</version>
    </dependency>
    <!-- MyBatis -->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>${mybatis.version}</version>
    </dependency>
    <!-- mybatis-spring整合包 -->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>1.3.1</version>
    </dependency>
    <!-- 第四部分：日志 -->
    <!-- 实现slf4j接口并整合 -->
    <dependency>
      <groupId>ch.qos.logback</groupId>
      <artifactId>logback-classic</artifactId>
      <version>1.1.1</version>
    </dependency>

  </dependencies>
  
</project>

下面开始写java代码：

在pojo包中新建Paper.java

package com.taneli.pojo;

public class Paper {
    private long paperId;
    private String paperName;
    private  int paperNum;
    private String paperDetail;

    public long getPaperId() {
        return paperId;
    }

    public void setPaperId(long paperId) {
        this.paperId = paperId;
    }

    public String getPaperName() {
        return paperName;
    }

    public void setPaperName(String paperName) {
        this.paperName = paperName;
    }

    public int getPaperNum() {
        return paperNum;
    }

    public void setPaperNum(int paperNum) {
        this.paperNum = paperNum;
    }

    public String getPaperDetail() {
        return paperDetail;
    }

    public void setPaperDetail(String paperDetail) {
        this.paperDetail = paperDetail;
    }
}

其中getter/setter方法可以在定义完私有属性之后使用IDEA提供的快捷键：ALT+Insert 来实现快速添加

在service包中新建接口 PaperService：

package com.taneli.service;

import com.taneli.pojo.Paper;

import java.util.List;

public interface PaperService {
    //添加数据
    int addPaper(Paper paper);

    //根据ID删除一个
    int deletePaperById(Long id);

    //修改数据
    int updatePaper(Paper paper);

    //查找单个数据
    Paper queryById(Long id);

    //查找所有数据
    List<Paper> queryAllPaper();
}

在service包下新建impl包，并在此包中新建PaperServiceImpl.java

package com.taneli.service.impl;

import com.taneli.dao.PaperDao;
import com.taneli.pojo.Paper;
import com.taneli.service.PaperService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;
@Service
public class PaperServiceImpl implements PaperService{

    @Autowired
    private PaperDao paperDao;

    @Override
    public int addPaper(Paper paper) {
        return paperDao.addPaper(paper);
    }

    @Override
    public int deletePaperById(Long id) {
        return paperDao.deletePaperById(id);
    }

    @Override
    public int updatePaper(Paper paper) {
        return paperDao.updatePaper(paper);
    }

    @Override
    public Paper queryById(Long id) {
        return paperDao.queryById(id);
    }


    @Override
    public List<Paper> queryAllPaper() {
        return paperDao.queryAllPaper();
    }

}

在dao包中新建接口 PaperDao.java

package com.taneli.dao;

import com.taneli.pojo.Paper;

import java.util.List;

public interface PaperDao {
    int addPaper(Paper paper);

    int deletePaperById(long id);

    int updatePaper(Paper paper);

    Paper queryById(long id);

    List<Paper> queryAllPaper();



}

在controller包中新建 PaperController.java

package com.taneli.controller;

import com.taneli.pojo.Paper;
import com.taneli.service.PaperService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PathVariable;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestMethod;

import java.util.List;

@Controller
@RequestMapping("/paper")
public class PaperController {

    @Autowired
    private PaperService paperService;

    //所有数据
    @RequestMapping("/allPaper")
    public String list(Model model){
        List<Paper> list=paperService.queryAllPaper();
        model.addAttribute("list",list);
        return "allpaper";
    }

    //到达添加路径
    @RequestMapping("toAddPaper")
    public String toAddPaper(){
        return "addPaper";
    }

    //增加单条数据
    @RequestMapping("/addPaper")
    public String addPaper(Paper paper){
        paperService.addPaper(paper);
        return  "redirect:/paper/allPaper";
    }

    //根据id删除单条数据
    @RequestMapping("/del/{paperId}")
    public String deletePaper(@PathVariable("paperId") Long id ){
         paperService.deletePaperById(id);
         return  "redirect:/paper/allPaper";
    }

    //根据id查找数据再修改单条数据
    @RequestMapping("/toUpdatePaper")
    public String toUpdatePaper(Model model, Long id) {
        model.addAttribute("paper", paperService.queryById(id));
        return "updatePaper";
    }

    //修改数据后保存跳到首页列表
    @RequestMapping("/updatePaper")
    public String updatePaper(Model model,Paper paper){
      paperService.updatePaper(paper);
      paper=paperService.queryById(paper.getPaperId());
      model.addAttribute("paper",paper);
      return "redirect:/paper/allPaper";
    }

}

在resource/mapper包下新建 PaperMapper.xml（mybatis框架mapper代理开发配置文件）

<?xml version="1.0" encoding="UTF-8" ?>
        <!DOCTYPE mapper
                PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
                "http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.taneli.dao.PaperDao">
  <resultMap id="paperResultMap" type="Paper">
      <id property="paperId" column="paper_id"></id>
      <result property="paperName" column="name"/>
      <result property="paperNum" column="number"/>
      <result property="paperDetail" column="detail"/>
  </resultMap>
    <insert id="addPaper" parameterType="Paper">
        INSERT INTO paper(paper_id,name,number,detail) VALUE (#{paperId},#{paperName}, #{paperNum}, #{paperDetail})
    </insert>

    <delete id="deletePaperById" parameterType="long">
        DELETE FROM paper WHERE paper_id=#{paperID}
    </delete>

    <update id="updatePaper" parameterType="Paper">
        UPDATE paper
        SET NAME = #{paperName},NUMBER = #{paperNum},detail = #{paperDetail}
        WHERE  paper_id = #{paperId}
    </update>

    <select id="queryById" resultType="Paper" parameterType="long">
        SELECT paper_id,name,number,detail
        FROM paper
        WHERE paper_id=#{paperId}
    </select>
    <select id="queryAllPaper" resultMap="paperResultMap">
        SELECT paper_id,name,number,detail
        FROM paper
    </select>
</mapper>

在resource/spring包下分别新建配置文件：spring-dao.xml , spring-mvc.xml , spring-service.xml

spring-dao.xml：（spring-mybatis整合配置文件）

<?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"
       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">
    <!-- 配置整合mybatis过程 -->
    <!-- 1.配置数据库相关参数properties的属性：${url} -->
    <!--<context:property-placeholder location="classpath:jdbc.properties"/>-->

    <!-- 2.数据库连接池 -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <!-- 配置连接池属性 -->
        <property name="driverClass" value="com.mysql.jdbc.Driver"/>
        <property name="jdbcUrl" value="jdbc:mysql://127.0.0.1:3306/ssm?serverTimezone=UTC&amp;characterEncoding=utf8"/>
        <property name="user" value="root"/>
        <property name="password" value="password"/>

        <!-- c3p0连接池的私有属性 -->
        <property name="maxPoolSize" value="30"/>
        <property name="minPoolSize" value="10"/>
        <!-- 关闭连接后不自动commit -->
        <property name="autoCommitOnClose" value="false"/>
        <!-- 获取连接超时时间 -->
        <property name="checkoutTimeout" value="10000"/>
        <!-- 当获取连接失败重试次数 -->
        <property name="acquireRetryAttempts" value="2"/>
    </bean>

    <!-- 3.配置SqlSessionFactory对象 -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <!-- 注入数据库连接池 -->
        <property name="dataSource" ref="dataSource"/>
        <!-- 配置MyBaties全局配置文件:mybatis-config.xml -->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
        <!-- 扫描pojo包 使用别名 -->
        <property name="typeAliasesPackage" value="com.taneli.pojo"/>
        <!-- 扫描sql配置文件:mapper需要的xml文件 -->
        <property name="mapperLocations" value="classpath:mapper/*.xml"/>
    </bean>

    <!-- 4.配置扫描Dao接口包，动态实现Dao接口，注入到spring容器中 -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!-- 注入sqlSessionFactory -->
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        <!-- 给出需要扫描Dao接口包 -->
        <property name="basePackage" value="com.taneli.dao"/>
    </bean>
</beans>

spring-mvc.xml：（spring mvc配置文件）

<?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:mvc="http://www.springframework.org/schema/mvc"
       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/mvc
    http://www.springframework.org/schema/mvc/spring-mvc-3.0.xsd">
    <!-- 配置SpringMVC -->
    <!-- 1.开启SpringMVC注解模式 -->
    <!-- 简化配置：
        (1)自动注册DefaultAnootationHandlerMapping,AnotationMethodHandlerAdapter
        (2)提供一些列：数据绑定，数字和日期的format @NumberFormat, @DateTimeFormat, xml,json默认读写支持
    -->
    <mvc:annotation-driven />

    <!-- 2.静态资源默认servlet配置
        (1)加入对静态资源的处理：js,gif,png
        (2)允许使用"/"做整体映射
     -->
    <mvc:default-servlet-handler/>

    <!-- 3.配置jsp 显示ViewResolver -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
        <property name="prefix" value="/WEB-INF/jsp/" />
        <property name="suffix" value=".jsp" />
    </bean>

    <!-- 4.扫描web相关的bean -->
    <context:component-scan base-package="com.taneli.controller" />
</beans>

spring-service.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">
    <!-- 扫描service包下所有使用注解的类型 -->
    <context:component-scan base-package="com.taneli.service" />

    <!-- 配置事务管理器 -->
    <bean id="transactionManager"
          class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <!-- 注入数据库连接池 -->
        <property name="dataSource" ref="dataSource" />
    </bean>
    <!-- 配置基于注解的声明式事务 -->
    <tx:annotation-driven transaction-manager="transactionManager" />
</beans>

在jdbc.properties文件中配置mysql数据库（这里的数据库名、表名，用户名，密码一定要记得修改！！！）。

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://127.0.0.1:3306/test?characterEncoding=utf8
jdbc.username=root
jdbc.password=password

在log4j.properties文件中配置日志设定

log4j.rootLogger=ERROR, stdout
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

在mybatis-config.xml文件中配置mybtis框架

<?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>
    <!-- 配置全局属性 -->
    <settings>
        <!-- 使用jdbc的getGeneratedKeys获取数据库自增主键值 -->
        <setting name="useGeneratedKeys" value="true" />

        <!-- 使用列别名替换列名 默认:true -->
        <setting name="useColumnLabel" value="true" />

        <!-- 开启驼峰命名转换:Table{create_time} -> Entity{createTime} -->
        <setting name="mapUnderscoreToCamelCase" value="true" />
    </settings>
</configuration>

配置web.xml文件

<!DOCTYPE web-app PUBLIC
        "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
        "http://java.sun.com/dtd/web-app_2_3.dtd" >

<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" metadata-complete="true">
  <display-name>Archetype Created Web Application</display-name>
  <servlet>
    <servlet-name>dispatcher</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <!-- 配置springMVC需要加载的配置文件
        spring-dao.xml,spring-service.xml,spring-mvc.xml
        Mybatis - > spring -> springmvc
     -->
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:spring/spring-*.xml</param-value>
    </init-param>
  </servlet>
  <servlet-mapping>
    <servlet-name>dispatcher</servlet-name>
    <!-- 默认匹配所有的请求 -->
    <url-pattern>/</url-pattern>
  </servlet-mapping>
  <filter>
    <filter-name>encodingFilter</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>
  </filter>

  <filter-mapping>
    <filter-name>encodingFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>
</web-app>