SSM-Spring、SpringMVC、MyBatis集成

1、 简介

SSM 包含三大框架:

• Spring MVC (web level)，采取 MVC 架构，意图取代麻烦的 Servlet 写法，简化 web 层
• MyBatis (dao level)，意图取代 jdbc 操作数据库，轻量级、灵活、高效
• Spring，提供了 IoC(容器，用来管理组装对象) 和 AoP(切面，用来自动增强对象功能) 功能，它用来将对象和其他框架组织在一起

2、 首先，创建项目

推荐使用 Maven 或者 Gradle 创建 ssm 项目。

可以选择在 Idea 下面，创建 Maven 或 Gradle 项目即可。

3、 其次，增加依赖(jar 包)

Maven 的配置文件是 pom.xml，想为项目添加依赖，只需要向 pom.xml 增加相关配置即可。

这是示例:

<?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.nf147</groupId>
  <artifactId>BookStore_SSM</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>war</packaging>

  <name>BookStore_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>
  </properties>

  <dependencies>
    <!--spring 所需要的 jar 包-->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-web</artifactId>
      <version>5.1.0.RELEASE</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-aop</artifactId>
      <version>5.1.0.RELEASE</version>
    </dependency>

    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-jdbc</artifactId>
      <version>5.1.0.RELEASE</version>
    </dependency>

    <!--spring mvc 的依赖-->
    <dependency>
      <groupId>org.springframework</groupId>
      <artifactId>spring-webmvc</artifactId>
      <version>5.1.0.RELEASE</version>
    </dependency>

    <!--mybatis jar 包-->
    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis</artifactId>
      <version>3.4.6</version>
    </dependency>

    <dependency>
      <groupId>org.mybatis</groupId>
      <artifactId>mybatis-spring</artifactId>
      <version>1.3.2</version>
    </dependency>

    <!--数据库相关 jar 包-->
    <dependency>
      <groupId>org.mariadb.jdbc</groupId>
      <artifactId>mariadb-java-client</artifactId>
      <version>2.3.0</version>
    </dependency>

    <dependency>
      <groupId>com.mchange</groupId>
      <artifactId>c3p0</artifactId>
      <version>0.9.5.2</version>
    </dependency>

    <!--其他-->
    <dependency>
      <groupId>javax.servlet</groupId>
      <artifactId>jstl</artifactId>
      <version>1.2</version>
    </dependency>

    <!-- 日志框架 -->
    <dependency>
      <groupId>log4j</groupId>
      <artifactId>log4j</artifactId>
      <version>1.2.17</version>
    </dependency>

    <!--用来单元测试的 jar 包-->
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>4.11</version>
      <scope>test</scope>
    </dependency>
  </dependencies>

  <build>
    <finalName>BookStore_SSM</finalName>
    <pluginManagement><!-- lock down plugins versions to avoid using Maven defaults (may be moved to parent pom) -->
      <plugins>
        <plugin>
          <artifactId>maven-clean-plugin</artifactId>
          <version>3.0.0</version>
        </plugin>
        <!-- see http://maven.apache.org/ref/current/maven-core/default-bindings.html#Plugin_bindings_for_war_packaging -->
        <plugin>
          <artifactId>maven-resources-plugin</artifactId>
          <version>3.0.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-compiler-plugin</artifactId>
          <version>3.7.0</version>
        </plugin>
        <plugin>
          <artifactId>maven-surefire-plugin</artifactId>
          <version>2.20.1</version>
        </plugin>
        <plugin>
          <artifactId>maven-war-plugin</artifactId>
          <version>3.2.0</version>
        </plugin>
        <plugin>
          <artifactId>maven-install-plugin</artifactId>
          <version>2.5.2</version>
        </plugin>
        <plugin>
          <artifactId>maven-deploy-plugin</artifactId>
          <version>2.8.2</version>
        </plugin>
      </plugins>
    </pluginManagement>
  </build>
</project>

　　

然后，点击 Maven 工具包的刷新，jar 包就会被自动下载并配置。

4、 之后，增加配置文件

基本只需要下面几个配置文件:

• resources/mybatis.xml, mybatis 的核心配置文件
• resources/spring-root.xml, spring 的核心配置文件
• resources/spring-web.xml, spring mvc 的配置文件，可以配置 springmvc 相关的东西
• web.xml, 因为是 web 项目，必须要配置 web.xml，让服务器启动的时候加载 spring 和 spring mvc
• log4j.properties，用来定义日志输出

mybatis.xml 示例:

<?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>
        <setting name="logImpl" value="LOG4J"/>
    </settings>
</configuration>

spring-root.xml 示例:

<?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">

    <!-- 启用注释 -->
    <!--@Component/@Service/@Repository/@Controller-->
    <context:component-scan base-package="com.nf147.bookstore_ssm.service" />

    <!-- 创建数据源 -->
    <bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="org.mariadb.jdbc.Driver" />
        <property name="jdbcUrl" value="jdbc:mariadb://localhost:3306/lagou" />
        <property name="user" value="root" />
        <property name="password" value="Qi1007.." />
    </bean>

    <!-- 配置 mybatis -->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean" >
        <property name="dataSource" ref="dataSource" />
        <property name="configLocation" value="classpath:mybatis.xml" />
        <property name="mapperLocations" value="classpath:mapper/*.xml" />
    </bean>

    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory" />
        <property name="basePackage" value="com.nf147.bookstore_ssm.dao" />
    </bean>

    <!-- 配置事务管理 -->

</beans>

spring-web.xml 示例:

<?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:contxt="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/cache http://www.springframework.org/schema/cache/spring-cache.xsd http://www.springframework.org/schema/mvc http://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <!--扫描包下面所有的 @Controller 注解的类，并将其实例化，放入容器-->
    <contxt:component-scan base-package="com.nf147.bookstore_ssm.web" />

    <!-- 启用mvc 的常用注解 -->
    <mvc:annotation-driven />

    <!-- 将所有的静态资源，交给 Servlet处理 -->
    <mvc:default-servlet-handler />

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

</beans>

web.xml 示例，用来驱动 spring 和 spring mvc:

<!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>
  <display-name>Archetype Created Web Application</display-name>

  <!--配置 Spring 的容器-->
  <context-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:spring-root.xml</param-value>
  </context-param>
  <listener>
    <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
  </listener>

  <!--配置 MVC 容器-->
  <!--将所有的请求，都交给 Spring MVC 处理-->
  <servlet>
    <servlet-name>app</servlet-name>
    <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
    <init-param>
      <param-name>contextConfigLocation</param-name>
      <param-value>classpath:spring-web.xml</param-value>
    </init-param>
  </servlet>
  <servlet-mapping>
    <servlet-name>app</servlet-name>
    <url-pattern>/</url-pattern>
  </servlet-mapping>

  <filter>
    <filter-name>charFilter</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>forceEncoding</param-name>
      <param-value>true</param-value>
    </init-param>
  </filter>
  <filter-mapping>
    <filter-name>charFilter</filter-name>
    <url-pattern>/*</url-pattern>
  </filter-mapping>

</web-app>

log4j.properties，用来配置日志:

# 全局配置: 只显示错误级别的日志，输出为名字为 stdou 的日志
log4j.rootLogger=ERROR, stdout

# MyBatis 的日志配置，只输出 com.nf147.bookstore_ssm.dao 包下产生 INFO 以及以上级别的日志
#TRACE为日志级别，可进行修改
log4j.logger.com.nf147.bookstore_ssm.dao=TRACE

# 定义名字为 stdout 的日志，将日志输出到控制台
log4j.appender.stdout=org.apache.log4j.ConsoleAppender
log4j.appender.stdout.layout=org.apache.log4j.PatternLayout
log4j.appender.stdout.layout.ConversionPattern=%5p [%t] - %m%n

然后，创建相关的目录结构，如图:

5、 然后就可以创建服务器，启动之了

之后就可以在 idea 里面创建应用服务器，将项目部署到上面，运行之。

6、 开始编码, 准备工作

创建表:

drop table if exists ssm_book;
create table ssm_book (
    bookid int auto_increment primary key,
    name varchar(20) not null,
    cnt int default 0
);

为其创建实现类:

package com.nf147.bookstore_ssm.entity;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

public class Book {
    private int bookid;
    private String name;
    private int cnt;

    public Book() {
    }

    public Book(int bookid, String name, int cnt) {
        this.bookid = bookid;
        this.name = name;
        this.cnt = cnt;
    }

    public Book(String name, int cnt) {
        this.name = name;
        this.cnt = cnt;
    }

    public int getBookid() {
        return bookid;
    }

    public void setBookid(int bookid) {
        this.bookid = bookid;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getCnt() {
        return cnt;
    }

    public void setCnt(int cnt) {
        this.cnt = cnt;
    }
}

7、 开始编码, dao 层示例

其创建 BookDAO 接口，实现数据库查询与操作:

package com.nf147.bookstore_ssm.dao;

import com.nf147.bookstore_ssm.entity.Book;

import java.util.List;

public interface BookDAO {

    //通过 id 获取图书
    Book getById(int bookid);

    //通过 名称 获取图书
    Book getByName(String bookName);

    //获取书籍数目
    int countAll();

    //获取所有图书
    List<Book> listAll();

    //新增图书
    int insert(Book book);

    //修改图书
    int update(Book book);

    //删除图书
    int delete(int bookid);

    //修改图书cnt
    int updateCnt(Book book);

    //添加操作
    int insertLog(String operation);
}

然后，为这个接口，编写相应 mapper.xml，可以看做这个 xml 是这个接口的实现类(由 mybatis 根据这个 xml 创建相应的实现类):

<?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.nf147.bookstore_ssm.dao.BookDAO">
    <insert id="insert" parameterType="com.nf147.bookstore_ssm.entity.Book">
        insert into ssm_book (name, cnt) values (#{name}, #{cnt})
    </insert>

    <insert id="insertLog" parameterType="String">
        insert into ssm_log (operation) values (#{operation})
    </insert>

    <insert id="update" parameterType="com.nf147.bookstore_ssm.entity.Book">
        update ssm_book
          set name = #{name}, cnt = #{cnt}
          where bookid = #{bookid}
    </insert>

    <update id="updateCnt" parameterType="com.nf147.bookstore_ssm.entity.Book">
        update ssm_book
          set cnt = cnt + #{cnt}
          where name = #{name}
    </update>

    <delete id="delete" parameterType="int">
        delete from ssm_book where bookid=#{bookid}
    </delete>

    <select id="getById" parameterType="int" resultType="com.nf147.bookstore_ssm.entity.Book">
            select bookid, name, cnt from ssm_book where bookid = #{bookid}
    </select>

    <select id="getByName" parameterType="String" resultType="com.nf147.bookstore_ssm.entity.Book">
            select bookid, name, cnt from ssm_book where name = #{name}
    </select>

    <select id="countAll" resultType="java.lang.Integer">
        select count(*) from ssm_book
    </select>

    <select id="listAll" resultType="com.nf147.bookstore_ssm.entity.Book">
        select bookid, name, cnt from ssm_book
    </select>

    <select id="listAllPager" resultType="com.nf147.bookstore_ssm.entity.Book">
        select bookid, name, cnt from ssm_book limit #{offset}, #{size}
    </select>
</mapper>

8、开始编码, service 层示例

需要有接口，有实现类，面向接口编程。

需要在实现类上，写 @Service 注解。

package com.nf147.bookstore_ssm.service;

import com.nf147.bookstore_ssm.entity.Book;

import java.util.List;

public interface BookService {

    //根据书籍id获取单本书籍
    Book getBookById(int bookid);

    //根据书籍名称获取单本书籍
    Book getBookByName(String bookName);

    //获取所有书籍
    List<Book> listAll();

    //添加书籍
    int insert(Book book);

    //修改书籍
    int update(Book book);

    //修改书籍库存
    int updateCnt(Book book);

    //删除书籍
    int delete(int bookid);

    //添加操作
    int insertLogs(String operation);
}

 实现接口：

package com.nf147.bookstore_ssm.service;

import com.nf147.bookstore_ssm.dao.BookDAO;
import com.nf147.bookstore_ssm.entity.Book;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;

import java.util.List;

@Service
public class BookServiceImpl implements BookService {

    @Autowired
    private BookDAO bookDAO;

    @Override
    public Book getBookById(int bookid) {
        return bookDAO.getById(bookid);
    }

    @Override
    public Book getBookByName(String bookName) {
        return bookDAO.getByName(bookName);
    }

    @Override
    public List<Book> listAll() { return bookDAO.listAll(); }

    @Override
    public int insert(Book book) {
        return bookDAO.insert(book);
    }

    @Override
    public int update(Book book) {
        return bookDAO.update(book);
    }

    @Override
    public int updateCnt(Book book) {
        return bookDAO.updateCnt(book);
    }

    @Override
    public int delete(int bookid) {
        return bookDAO.delete(bookid);
    }

    @Override
    public int insertLogs(String operation) {
        return bookDAO.insertLog(operation);
    }
}

9、开始编码, web 层示例

简单示例:

package com.nf147.bookstore_ssm.web;

import com.nf147.bookstore_ssm.service.BookService;
import com.nf147.bookstore_ssm.dao.BookDAO;
import com.nf147.bookstore_ssm.entity.Book;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.servlet.ModelAndView;

import java.util.List;

@Controller
public class BookController {

    @Autowired
    private BookService bookService;

    @Autowired
    private BookDAO bookDAO;

    @RequestMapping("/book/{id}")
    public ModelAndView getBook(@PathVariable("id") int bookid) {
        ModelAndView mv = new ModelAndView("book_detail");
        Book book = bookService.getBookById(bookid);
        mv.addObject("book", book);
        return mv;
    }

    @RequestMapping("/bookAll")
    public ModelAndView bookAll() {
        ModelAndView mv = new ModelAndView("book_list");
        List<Book> bookList = bookService.listAll();
        mv.addObject("books", bookList);
        return mv;
    }

    @RequestMapping("/form")
    public ModelAndView form() {
        ModelAndView mv = new ModelAndView("book_add");
        return mv;
    }

    @RequestMapping("/updateForm/{id}")
    public ModelAndView updateForm(@PathVariable("id") int bookid) {
        ModelAndView mv = new ModelAndView("book_update");
        mv.addObject("bookid", bookid);
        return mv;
    }

    @RequestMapping("/updateName")
    public int updateCnt(String name, int count) {
        Book book = new Book();
        book.setName(name);
        book.setCnt(count);
        int num = bookService.updateCnt(book);
        return num;
    }

    @RequestMapping("/bookUpdate")
    public ModelAndView bookUpdate(int id,String name, int count) {
        Book book = new Book();
        book.setBookid(id);
        book.setName(name);
        book.setCnt(count);
        int num = bookService.update(book);
        if(num > 0) {
            bookService.insertLogs("update ssm_book set name = "+name+", cnt = "+count+" where bookid = "+id+"");
            return bookAll();
        }else
            return updateForm(id);
    }

    @RequestMapping("/bookAdd")
    public ModelAndView bookAdd(String name, int count) {
        Book book = new Book();
        book.setName(name);
        book.setCnt(count);
        Book upBook = bookService.getBookByName(name);
        if (upBook != null) {
            int num = updateCnt(name, count);
            if (num > 0){
                bookService.insertLogs("update ssm_book set cnt = cnt + "+count+" where name = "+name+"");
                return bookAll();
            }
        } else {
            int num = bookService.insert(book);
            if (num > 0) {
                bookService.insertLogs("insert into ssm_book (name, cnt) values ("+name+", "+count+")");
                return bookAll();
            }else
                return form();
        }
        return null;
    }

    @RequestMapping("/delete/{id}")
    public ModelAndView delete(@PathVariable("id") int bookid) {
        int num = bookService.delete(bookid);
        if (num > 0){
            bookService.insertLogs("delete from ssm_book where bookid="+bookid+"");
            return bookAll();
        }
        return null;
    }

}