SSM(Vue3+ElementPlus+Axios+SSM前后端分离)【四】

SSM(Vue3+ElementPlus+Axios+SSM前后端分离)–基础环境搭建【四】

项目介绍

项目功能/界面

● SSM 整合项目界面

创建表，使用逆向工程生成Bean、XxxMapper 和XxxMapper.xml

1. 创建furns_ssm 数据库和furns 表

-- 创建furns_ssm
DROP DATABASE IF EXISTS furns_ssm;
CREATE DATABASE furns_ssm;
USE furns_ssm;
-- 创建家居表
CREATE TABLE furn(
`id` INT(11) PRIMARY KEY AUTO_INCREMENT, ## id
`name` VARCHAR(64) NOT NULL, ## 家居名
`maker` VARCHAR(64) NOT NULL, ## 厂商
`price` DECIMAL(11,2) NOT NULL, ## 价格
`sales` INT(11) NOT NULL, ## 销量
`stock` INT(11) NOT NULL, ## 库存
`img_path` VARCHAR(256) NOT NULL ## 照片路径
);

使用MyBatis Generator 逆向工程生成bean mapper 接口和mapper.xml

当然也可以自己写,如果在开发中, 逆向工程生成的代码， 不能满足需要，再自己编写.

引入MyBatis Generator 包, 在pom.xml 配置

    junit
    junit
    4.11
    test

 


    org.mybatis.generator
    mybatis-generator-core
    1.4.0

创建furns_ssm\mbg.xml

参考文档https://mybatis.org/generator/ 进行配置， 这里给出了一个模板xml ,在上面修改即可

DOCTYPE generatorConfiguration
        PUBLIC "-//mybatis.org//DTD MyBatis Generator Configuration 1.0//EN"
        "http://mybatis.org/dtd/mybatis-generator-config_1_0.dtd">
<generatorConfiguration>
    <context id="DB2Tables" targetRuntime="MyBatis3">
        
        <commentGenerator>
            <property name="suppressAllComments" value="true"/>
        commentGenerator>
        
        注意记得把//删掉然后写自己的密码和端口
        jdbcConnection>
        <javaTypeResolver>
            <property name="forceBigDecimals" value="false"/>
        javaTypeResolver>
        
        <javaModelGenerator targetPackage="com.nlc.furn.bean" targetProject=".\src\main\java">
            <property name="enableSubPackages" value="true"/>
            <property name="trimStrings" value="true"/>
        javaModelGenerator>
        
        <sqlMapGenerator targetPackage="mapper" targetProject=".\src\main\resources">
            <property name="enableSubPackages" value="true"/>
        sqlMapGenerator>
        
        <javaClientGenerator type="XMLMAPPER" targetPackage="com.nlc.furn.dao" targetProject=".\src\main\java">
            <property name="enableSubPackages" value="true"/>
        javaClientGenerator>
        
        <table tableName="furn" domainObjectName="Furn">table>
    context>
generatorConfiguration>

创建文件\test\MBGTest.java

RunningMyBatis Generator , 生成相关bean, mapper 接口和mapper.xml 参考官方问题来修改, 并完成测试

public class MBGTest {

    @Test
    public void generator() throws Exception {

        List<String> warnings = new ArrayList<String>();
        boolean overwrite = true;
        //这里要指定你自己配置的mbg.xml
        //如果这样访问，需要将文件放在项目下
        File configFile = new File("mbg.xml");
        ConfigurationParser cp = new ConfigurationParser(warnings);
        Configuration config = cp.parseConfiguration(configFile);
        DefaultShellCallback callback = new DefaultShellCallback(overwrite);
        MyBatisGenerator myBatisGenerator = new MyBatisGenerator(config, callback, warnings);
        myBatisGenerator.generate(null);
		System.out.println("逆向生成OK");
    }
}

使用Junit 测试Spring 和MyBatis 是否整合成功, 能通过MyBatis 添加furn 到数据库

1. 修改bean: Furn.java
   

创建furns_ssm\src\test\java\com\nlc\furns\dao\FurnMapperTest.java完成对furn 表的crud 测试操作

public class FurnMapperTest {
 
    @Test
    public void insertSelective() {
 
        //1. 获取到容器
        ApplicationContext ioc =
                new ClassPathXmlApplicationContext("applicationContext.xml");
        //2获取FurnMapper
        FurnMapper furnMapper = ioc.getBean(FurnMapper.class);
        //System.out.println("furnMapper--" + furnMapper.getClass());
        //3.添加数据
        Furn furn =
                new Furn(null, "北欧风格沙发~~", "与之家~~", new BigDecimal(180), 666,
                        70, "assets/images/product-image/1.jpg");
 
        int affected = furnMapper.insertSelective(furn);
        System.out.println("affected--" + affected);
        System.out.println("操作成功~");
    }
 
 
    @Test
    public void deleteByPrimaryKey() {
 
        //1. 获取到容器
        ApplicationContext ioc =
                new ClassPathXmlApplicationContext("applicationContext.xml");
        //2获取FurnMapper
        FurnMapper furnMapper = ioc.getBean(FurnMapper.class);
 
        int affected = furnMapper.deleteByPrimaryKey(6);
        System.out.println("affected--" + affected);
        System.out.println("操作成功");
    }
 
    @Test
    public void updateByPrimaryKey() {
 
        //1. 获取到容器
        ApplicationContext ioc =
                new ClassPathXmlApplicationContext("applicationContext.xml");
        //2获取FurnMapper
        FurnMapper furnMapper = ioc.getBean(FurnMapper.class);
 
        Furn furn = new Furn();
        furn.setId(5);
        furn.setName("风格家居-小沙发");
 
        //会修改所有的字段，如果没有设置字段对应的属性值，那么默认是null
        //int affected = furnMapper.updateByPrimaryKey(furn);
 
        //根据你设置属性对应字段，生成sql语句
        int affected = furnMapper.updateByPrimaryKeySelective(furn);
        System.out.println("affected--" + affected);
        System.out.println("操作成功~");
 
    }
 
    @Test
    public void selectByPrimaryKey() {
 
        //1. 获取到容器
        ApplicationContext ioc =
                new ClassPathXmlApplicationContext("applicationContext.xml");
        //2获取FurnMapper
        FurnMapper furnMapper = ioc.getBean(FurnMapper.class);
 
        Furn furn = furnMapper.selectByPrimaryKey(1);
        System.out.println("furn--" + furn);
        System.out.println("操作成功~");
    }
}

注意事项和细节说明

insertSelective 和insert 的区别

1. insertSelective–选择性保存数据；
   比如User 里面有三个字段:id，name，age，password
   但是只设置了一个字段；
   User u=new user();
   u.setName(“张三”)；
   insertSelective(u)；

2. insertSelective 执行对应的sql 语句的时候，只插入对应的name 字段；(主键是自动添加的，默认插入为空)

   insert into tb_user （id，name） value （null，“张三”）；

3. 而insert 则是不论设置多少个字段，统一都要添加一遍，不论你设置几个字段，即使是一个
   User u=new user();
   u.setName(“张三”);
   insert(u);
   insert into tb_user (id，name，age，password) value (null，“张三”，null，null)