mybatis逆向工程 + 通用mapper

pom.xml

        <dependency>
            <groupId>mysqlgroupId>
            <artifactId>mysql-connector-javaartifactId>
            <version>8.0.11version>
        dependency>

        
        <dependency>
            <groupId>org.mybatis.spring.bootgroupId>
            <artifactId>mybatis-spring-boot-starterartifactId>
            <version>1.3.1version>
        dependency>

        
        <dependency>
            <groupId>tk.mybatisgroupId>
            <artifactId>mapper-spring-boot-starterartifactId>
            <version>1.2.4version>
        dependency>

        
        <dependency>
            <groupId>org.mybatis.generatorgroupId>
            <artifactId>mybatis-generatorartifactId>
            <version>1.3.7version>
        dependency>
        <dependency>
            <groupId>org.mybatis.generatorgroupId>
            <artifactId>mybatis-generator-maven-pluginartifactId>
            <version>1.3.7version>
        dependency>

application.properties

# mybatis 配置
mybatis.type-aliases-package=com.demo.pojo
mybatis.mapper-locations=classpath:mapper/*.xml

# 通用 Mapper 配置
mapper.mappers=com.demo.MyMapper
mapper.not-empty=false
mapper.identity=MYSQL

generatorConfig.xml

和pom.xml在同级目录

<generatorConfiguration>

    <properties resource="datasource.properties">properties>

    <context id="MysqlContext" targetRuntime="MyBatis3Simple" defaultModelType="flat">
        <property name="beginningDelimiter" value="`"/>
        <property name="endingDelimiter" value="`"/>

        <plugin type="org.mybatis.generator.plugins.SerializablePlugin" />

        
        <plugin type="org.mybatis.generator.plugins.ToStringPlugin" />
   
        
        <plugin type="tk.mybatis.mapper.generator.MapperPlugin">
            <property name="mappers" value="com.demo.utils.MyMapper"/>
        plugin>
        
		
        <plugin type="org.mybatis.generator.plugins.UnmergeableXmlMappersPlugin" />
        
        
        
        <commentGenerator>
            
            <property name="suppressAllComments" value="false" />
        commentGenerator>

        

        

        
        

        <jdbcConnection driverClass="com.mysql.cj.jdbc.Driver"
                        connectionURL="${db.url}"
                        userId="${db.username}"
                        password="${db.password}">
        jdbcConnection>
        
        
        <javaModelGenerator targetPackage="com.demo.pojo" targetProject="src/main/java">
            
            <property name="constructorBased" value="true"/>
        javaModelGenerator>

		
        <sqlMapGenerator targetPackage="mapper" targetProject="src/main/resources"/>

		
        <javaClientGenerator targetPackage="com.demo.mapper" targetProject="src/main/java"
                             type="XMLMAPPER"/>

		
		 <table tableName="device" domainObjectName="Device">
            
            <generatedKey  column="device_id" sqlStatement="SELECT LAST_INSERT_ID()"/>
        table>
        <table tableName="print_file" domainObjectName="PrintFile">
            <generatedKey  column="file_id" sqlStatement="SELECT LAST_INSERT_ID()"/>
        table>
		 
    context>
generatorConfiguration>

MyMapper

路径 com.demo.utils.MyMapper

import tk.mybatis.mapper.common.Mapper;
import tk.mybatis.mapper.common.MySqlMapper;

public interface MyMapper<T> extends Mapper<T>, MySqlMapper<T> {
    //TODO
    //FIXME 特别注意，该接口不能被扫描到，否则会出错
}

最后的执行文件GeneratorDisplay.java

import org.mybatis.generator.api.MyBatisGenerator;
import org.mybatis.generator.config.Configuration;
import org.mybatis.generator.config.xml.ConfigurationParser;
import org.mybatis.generator.internal.DefaultShellCallback;

import java.io.File;
import java.util.ArrayList;
import java.util.List;
public class GeneratorDisplay {

	public void generator() throws Exception{

		List<String> warnings = new ArrayList<String>();
		boolean overwrite = true;
		//指定 逆向工程配置文件
		File configFile = new File("src/main/resources/generatorConfig.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);

	}

	public static void main(String[] args) throws Exception {
		try {
			GeneratorDisplay generatorSqlmap = new GeneratorDisplay();
			generatorSqlmap.generator();
		} catch (Exception e) {
			e.printStackTrace();
		}

	}
}

datasource.properties

db.url=jdbc:mysql://localhost:3306/gdpt_posmart_office?serverTimezone=UTC&useSSL=false
db.username=root
db.password=root
# 其他参数

常见问题

1.热部署冲突，提示 tk.mybatis.mapper.MapperException: tk.mybatis.mapper.provider.EmptyProvider中缺少selectOne方法!

https://blog.csdn.net/yinaoxiao7661/article/details/88737604

2.获取自增长id

方式一：
添加
useGeneratedKeys=“true” keyProperty=“fileId” keyColumn=“file_id”

<insert id="myInsert" parameterType="com.gdpt.crawlerprint.pojo.PrintFile"
          useGeneratedKeys="true" keyProperty="fileId" keyColumn="file_id">
    insert into cp_print_file (user_id, filename,
    file_type, upload_date)
    values (#{userId,jdbcType=INTEGER}, #{filename,jdbcType=VARCHAR},
    #{fileType,jdbcType=BIT}, #{uploadDate,jdbcType=TIMESTAMP})
  insert>

获取自增长id

		printFileMapper.myInsert(printFile);
		int id = 0;
        if (printFile.getFileId() != null){
            id = printFile.getFileId();
        }

方式二：
generatorConfig.xml配置中

		<table tableName="print_file" domainObjectName="PrintFile">
            
            <generatedKey  column="file_id" sqlStatement="SELECT LAST_INSERT_ID()"/>
        table>

获取自增长id

		printFileMapper.insert(printFile);
		int id = 0;
        if (printFile.getFileId() != null){
            id = printFile.getFileId();
        }

3.常用接口解释

    //（1）mapper基础接口
    //select接口
      List<VirtualIpBean> vipList = vipMapper.select(vipBean);//根据实体中的属性值进行查询，查询条件使用等号
    VirtualIpBean vip = vipMapper.selectOne(vipBean);//根据实体中的属性进行查询，只能有一个返回值，有多个结果是抛出异常，查询条件使用等号
    List<VirtualIpBean> vipList2 = vipMapper.selectAll();//查询全部结果，select(null)方法能达到同样的效果
    VirtualIpBean vip2 = vipMapper.selectByPrimaryKey(1);//根据主键字段进行查询，方法参数必须包含完整的主键属性，查询条件使用等号
    int count = vipMapper.selectCount(vipBean);//根据实体中的属性查询总数，查询条件使用等号
    //insert接口
    int a = vipMapper.insert(vipBean);//保存一个实体，null的属性也会保存，不会使用数据库默认值
    int a1 = vipMapper.insertSelective(vipBean);//保存实体，null的属性不会保存，会使用数据库默认值
    //update接口
    int b = vipMapper.updateByPrimaryKeySelective(vipBean);//根据主键更新属性不为null的值
    int c = vipMapper.updateByPrimaryKey(vipBean);//根据主键更新实体全部字段，null值会被更新
    //delete接口
    int d = vipMapper.delete(vipBean);//根据实体属性作为条件进行删除，查询条件使用等号
    int e = vipMapper.deleteByPrimaryKey(1);//根据主键字段进行删除，方法参数必须包含完整的主键属性
    //（2）Example方法
    Example example = new Example(VirtualIpBean.class);
    example.createCriteria().andEqualTo("id", 1);
    example.createCriteria().andLike("val", "1");
    //自定义查询
    List<VirtualIpBean> vipList3 = vipMapper.selectByExample(example);