SpringBoot+JDBC

 

添加依赖 

<dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency><dependency>
	<groupId>org.springframework.boot</groupId>
	<artifactId>spring-boot-starter-jdbc</artifactId>
</dependency>

从一张或多张表 查询出 某些需要的字段，并把它转为实体类。

比如有两张表table_a 和 table_b ，它们字段很多，某个功能只需要从这两张表中 获取某几个字段。

这样就可以新建一个实体类newEntity，它的字段就是需要获取到的字段。

然后用jdbc执行查询，并把结果转换成这个实体类。

 

新建实体类

public class NewEntity {

	private String name;
	private Integer age;

	public String getName() {
		return name;
	}

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

	public Integer getAge() {
		return age;
	}

	public void setAge(Integer age) {
		this.age = age;
	}

}

　　

执行查询，并把查询结果转为实体类List

import java.util.List;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.jdbc.core.BeanPropertyRowMapper;
import org.springframework.jdbc.core.JdbcTemplate;
import org.springframework.stereotype.Service;

@Service
public class NewEntityServiceImplTest  {

	@Autowired
	private JdbcTemplate jdbcTemplate;

	public List<NewEntity> findNewEntity(String strsqlColumn, String msac, String sbac) {

		String sqlString = "select ''as name,'' as age" + " from TB_ENTITY   where class = '1' ";

		List<NewEntity> newEntities = jdbcTemplate.query(sqlString, new Object[] {},
				new BeanPropertyRowMapper<NewEntity>(NewEntity.class));
		return newEntities;

	}


//如果结果只有一条
	public NewEntity findNewEntity(String strsqlColumn, String msac, String sbac) {

		String sqlString = "select ''as name,'' as age" + " from TB_ENTITY   where class = '1' ";

		 NewEntity newEntity = jdbcTemplate.queryForObject(sqlString, NewEntity.class);
		return newEntity;

	}

}