MyBatisPlus学習ノート(一)Mapper CRUDインタフェースWrapper条件コンストラクタ

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MyBatis Plus
MyBatisPlus学習ノート(一)Mapper CRUDインタフェースWrapper条件コンストラクタ
文書ディレクトリ
  • MyBatisPlus学習ノート(一)Mapper CRUDインタフェースWrapper条件コンストラクタ
  • Mapper CRUDインタフェース
  • 基礎構成
  • データベースが正常に接続されたかどうかを確認する
  • 汎用CRUD
  • 汎用CRUD insert
  • 汎用CRUD update
  • 汎用CRUD select
  • 汎用CRUD delete
  • 条件コンストラクタ(Wrapper)
  • 条件コンストラクタupdate
  • 条件コンストラクタselect
  • 条件コンストラクタdelete
    • Mapper CRUDインタフェース
    基本構成
  • 以下のすべての方法は、この基礎の下で
    • に確立されている.
  • public class TestMP {
	
	ApplicationContext applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
	
	EmployeeMapper empMapper = applicationContext.getBean("employeeMapper", EmployeeMapper.class);
    // ...
}
  • applicationContext.xml 
    
<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"
	xmlns:mybatis-spring="http://mybatis.org/schema/mybatis-spring"
	xsi:schemaLocation="http://mybatis.org/schema/mybatis-spring http://mybatis.org/schema/mybatis-spring-1.2.xsd
		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-4.0.xsd
		http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-4.0.xsd">
		
		
	<context:property-placeholder location="classpath:db.properties"/>
	<bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
		<property name="driverClass" value="${jdbc.driver}">property>
		<property name="jdbcUrl" value="${jdbc.url}">property>
		<property name="user" value="${jdbc.user}">property>
		<property name="password" value="${jdbc.password}">property>
	bean>
	
	<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
		<property name="dataSource" ref="dataSource">property>
	bean>
	
	<tx:annotation-driven transaction-manager="dataSourceTransactionManager"/>
	
	
	<bean id="sqlSessionFactory" class="com.baomidou.mybatisplus.spring.MybatisSqlSessionFactoryBean">
		<property name="dataSource" ref="dataSource">property>
		<property name="configLocation" value="classpath:mybatis-config.xml">property>
		
		<property name="typeAliasesPackage" value="com.fu.bean">property>		
		
		
		<property name="globalConfig" ref="globalConfiguration">property>
	bean>
	
	
	
		
		<property name="dbColumnUnderline" value="true">property>
		
		
		<property name="idType" value="0">property>
		
		
		<property name="tablePrefix" value="tbl_">property>
	bean>
	
	
	<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
		<property name="basePackage" value="com.fu.mapper">property>
	bean>
beans>
  • mybatis-config.xml 
    

	
<configuration>
configuration>
  • db.properties 
    jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/xxx
jdbc.user=xxx
jdbc.password=xxx
#  xxx
  • log4j.xml 
    

 
<log4j:configuration xmlns:log4j="http://jakarta.apache.org/log4j/">
 
 <appender name="STDOUT" class="org.apache.log4j.ConsoleAppender">
   <param name="Encoding" value="UTF-8" />
   <layout class="org.apache.log4j.PatternLayout">
    <param name="ConversionPattern" value="%-5p %d{MM-dd HH:mm:ss,SSS} %m  (%F:%L) 
    "     />    
   layout>
 appender>
 <logger name="java.sql">
   <level value="debug" />
 logger>
 <logger name="org.apache.ibatis">
   <level value="info" />
 logger>
 <root>
   <level value="debug" />
   <appender-ref ref="STDOUT" />
 root>
log4j:configuration>

    • データベースが正常に接続されていることを確認
  • @Test
public void testDatasource() throws SQLException {
    DataSource sd = applicationContext.getBean("dataSource", DataSource.class);
    System.out.println(sd);
    Connection connection = sd.getConnection();
    System.out.println(connection);
}
//     com.mchange.v2.c3p0.impl.NewProxyConnection@353352b6 [wrapping: com.mysql.jdbc.JDBC4Connection@4681c175]

    • 汎用CRUD
    汎用CRUD insert
    public void testInsertAllColumn() {
    Employee employee = new Employee();
    employee.setLastName("efda");
    // insert      ，                  ，                 SQL   
    Integer result = empMapper.insertAllColumn(employee);
    // INSERT INTO tbl_employee ( last_name,email,gender,age ) VALUES ( ?,?,?,? )

    // insertAllColumn      ，         ，              SQL   
    //		Integer insert = empMapper.insert(employee);
    // INSERT INTO tbl_employee ( last_name ) VALUES ( ? )
    System.out.println("result="+result);

    //               
    Integer key = employee.getId();
    System.out.println("key:" + key );
}

    汎用CRUD update
    public void testUpdate() {
    Employee employee = new Employee();
    employee.setLastName("az");
    employee.setAge(24);
    employee.setGender(1);
    employee.setId(4);

    //		Integer update = empMapper.updateById(employee);
    // UPDATE tbl_employee SET last_name=?, gender=?, age=? WHERE id=? 

    //		Integer update = empMapper.updateAllColumnById(employee);
    // UPDATE tbl_employee SET last_name=?,email=?,gender=?,age=? WHERE id=?

    String setSql = "age = 18 where id = 5";
    Integer update = empMapper.updateForSet(setSql, null);
    // UPDATE tbl_employee SET age = 18 where id = 5
    System.out.println("update="+update);
}

    汎用CRUD select
    	public void testSelect() {
		// 1.   id  
//		Employee employee = empMapper.selectById(2);
		// SELECT id,last_name AS lastName,email,gender,age FROM tbl_employee WHERE id=?
//		System.out.println(employee);
		
		//2.     id        
//		List ids = new ArrayList<>();
//		ids.add(1);
//		ids.add(2);
//		ids.add(3);
//		ids.add(4);
//		List list = empMapper.selectBatchIds(ids);
//		//  SELECT id,last_name AS lastName,email,gender,age FROM tbl_employee WHERE id IN ( ? , ? , ? , ? )
//		System.out.println(list);
		
		//3.              age  +  lastName
		//           ，        
//		Employee employee = new Employee();
//		employee.setLastName("qaaz");
//		employee.setAge(18);
//		Employee employeeOne = empMapper.selectOne(employee);
//		// SELECT id,last_name AS lastName,email,gender,age FROM tbl_employee WHERE last_name=? AND age=?
//		System.out.println(employeeOne);
		
		
		//4.   Map      
//		Map map = new HashMap<>();
//		map.put("last_name", "az");
//		map.put("gender", 1);
//		List list = empMapper.selectByMap(map);
		// SELECT id,last_name AS lastName,email,gender,age FROM tbl_employee WHERE gender = ? AND last_name = ?
		
		//5.     
		//    ，    ，      ，          
		List<Employee> list = empMapper.selectPage(new Page<>(2,3), null);
		// SELECT id,last_name AS lastName,email,gender,age FROM tbl_employee
		System.out.println(list);
		
	}

    汎用CRUD delete
    	public void testDelete() {
		// 1.   id  
//		Integer result = empMapper.deleteById(1);
		// DELETE FROM tbl_employee WHERE id=?
		
		//2.     id    
//		List ids = new ArrayList<>();
//		ids.add(1);
//		ids.add(2);
//		ids.add(3);
//		Integer result = empMapper.deleteBatchIds(ids);
		// DELETE FROM tbl_employee WHERE id IN ( ? , ? , ? )
		
		//3.   Map      
		//              
		Map<String, Object> map = new HashMap<>();
		map.put("last_name", "qaaz");
		map.put("age", 18);
		Integer result = empMapper.deleteByMap(map);
		// DELETE FROM tbl_employee WHERE last_name = ? AND age = ?
		System.out.println("result="+result);
	}

    条件コンストラクタ(Wrapper)
  • 概要:条件コンストラクタはwrapperという抽象クラスから構成され、このクラスには2つのサブクラスがあり、それぞれEntityWrapperとConditionの2つのクラスであり、2つのサブクラスの用法は同じであり、この例ではEntityWrapperを用いて
    • を紹介する.
  • [外部リンクピクチャの転送失敗(img-GjkVZoIA-156495361812)(assets/1.png)]
    • 条件コンストラクタupdate
    	public void wrapperUpdate() {
		Employee employee = new Employee();
		employee.setLastName("kongming");
		employee.setAge(20);
		employee.setGender(1);
		
		Integer update = empMapper.update(employee, new EntityWrapper<Employee>()
				.eq("last_name", "efda")
				.eq("gender", 0)
				);
		// UPDATE tbl_employee SET last_name=?, gender=?, age=? WHERE (last_name = ? AND gender = ?)
		System.out.println("update="+update);
	}

    条件コンストラクタselect
    	public void wrapperSelect() {
		// 1.          
		//      qaaz，    18~40  ，     ，     q  
/*		List list = empMapper.selectList(new EntityWrapper()
				//          
				.eq("last_name", "qaaz")
				.between("age", 18, 40)
				.or()		// (last_name = ? AND age BETWEEN ? AND ? OR gender = ? AND last_name LIKE ?) 
				//.orNew()	// (last_name = ? AND age BETWEEN ? AND ?) OR (gender = ? AND last_name LIKE ?)
				.eq("gender", 1)
				.like("last_name", "q")
				);
		System.out.println(list);
		*/
		
		// 2.         
//		Integer count = empMapper.selectCount(new EntityWrapper().eq("gender", 1));
//		System.out.println("count="+count);
		
		// 3.         ，          
//		List list = empMapper.selectObjs(new EntityWrapper().eq("gender", 1));
//		System.out.println(list);
		
		// 4.       ，   
		//       
/*		List> list = empMapper.selectMapsPage(new Page(2, 3), new EntityWrapper()
//				.orderAsc(Arrays.asList(new String[] {"age"} ))		//  
				.orderDesc(Arrays.asList(new String[] {"age"} ))	//    
				);
		// SELECT id,last_name AS lastName,email,gender,age FROM tbl_employee ORDER BY age DESC
		System.out.println(list);
		*/
		
		// 5.     ,     
		List<Employee> list = empMapper.selectList(new EntityWrapper<Employee>()
				.last("limit 1,3"));
		// .last()    sql      ( sql     ) 
		// SELECT id,last_name AS lastName,email,gender,age FROM tbl_employee limit 1,3
		System.out.println(list);
	}

    条件コンストラクタdelete
    public void wrapperDelete() {
		Integer delete = empMapper.delete(new EntityWrapper<Employee>()
				.like("last_name", "s")
				);
		// DELETE FROM tbl_employee WHERE (last_name LIKE ?)
		// Parameters: %s%(String)         % 
		System.out.println("delete = "+delete);
	}
    判断環境はiOSまたはAndroid
    赤い帽子OSP 10 NFV配置ガイド:4.6.OVS-DPDKインタフェースのMTU値の設定