Spring Boot JDBC

JDBC详解

Java Data Base Connectivity,是一种用于执行SQL语句的Java API，可以为多种关系数据库提供统一访问，它由一组用Java语言编写的类和接口组成。不管是Hibernate，还是JPA或者MyBatis都是对JDBC做了一次封装。

Spring简化了JDBC那些内容

Spring JDBC抽象框架所带来的价值将在以下几个方面得以体现：（注：使用了Spring JDBC抽象框架之后，应用开发人员只需要完成斜体字部分的编码工作。）

	定义数据库连接参数打开数据库连接声明SQL语句预编译并执行SQL语句遍历查询结果（如果需要的话）处理每一次遍历操作处理抛出的任何异常处理事务关闭数据库连接

项目图片

在这里插入图片描述

pom.xml

只需要在pom.xml引入需要的数据库配置，就会自动访问此数据库，如果需要配置其他数据库，可以在application.properties进行添加

默认使用org.apache.tomcat.jdbc.pool.DataSource创建连接池

<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.jege.spring.boot</groupId><artifactId>spring-boot-jdbc</artifactId><version>0.0.1-SNAPSHOT</version><packaging>jar</packaging><name>spring-boot-jdbc</name><url>http://maven.apache.org</url><!-- 公共spring-boot配置，下面依赖jar文件不用在写版本号 --><parent><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-parent</artifactId><version>1.4.1.RELEASE</version><relativePath /></parent><properties><project.build.sourceEncoding>UTF-8</project.build.sourceEncoding><java.version>1.8</java.version></properties><dependencies><!-- 持久层 --><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-jdbc</artifactId></dependency><!-- h2内存数据库 --><dependency><groupId>com.h2database</groupId><artifactId>h2</artifactId><scope>runtime</scope></dependency><dependency><groupId>org.springframework.boot</groupId><artifactId>spring-boot-starter-test</artifactId><scope>test</scope></dependency></dependencies><build><finalName>spring-boot-jdbc</finalName><plugins><plugin><groupId>org.apache.maven.plugins</groupId><artifactId>maven-compiler-plugin</artifactId><configuration><source>${java.version}</source><target>${java.version}</target></configuration></plugin></plugins></build>
</project>

模型对象User

package com.jege.spring.boot.jdbc.entity;/*** 模型对象*/
public class User {private Long id;private String name;private Integer age;public User() {}public User(String name, Integer age) {this.name = name;this.age = age;}

持久层实现类UserDaoImpl

package com.jege.spring.boot.jdbc.dao.impl;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.Repository;import com.jege.spring.boot.jdbc.dao.IUserDao;
import com.jege.spring.boot.jdbc.entity.User;/*** jdbc CRUD*/
@Repository
public class UserDaoImpl implements IUserDao {@AutowiredJdbcTemplate jdbcTemplate;@Overridepublic void dropTable() {jdbcTemplate.update("drop table t_user if exists");}@Overridepublic void createTable() {jdbcTemplate.update("create table t_user (id bigint generated by default as identity, age integer, name varchar(255), primary key (id))");}@Overridepublic void save(User user) {jdbcTemplate.update("insert into t_user(name,age) values(?,?)", user.getName(), user.getAge());}@Overridepublic List<User> findAll() {return jdbcTemplate.query("select id,name,age from t_user", BeanPropertyRowMapper.newInstance(User.class));}@Overridepublic void deleteAll() {jdbcTemplate.update("delete from t_user");}@Overridepublic List<User> findByNameLike(String name) {return jdbcTemplate.query("select id,name,age from t_user where name like ?", new Object[] { name },BeanPropertyRowMapper.newInstance(User.class));}}

不需要application.properties

测试类UserDaoTest

package com.jege.spring.boot.data.jpa;import static org.assertj.core.api.Assertions.assertThat;import org.junit.After;
import org.junit.Before;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;import com.jege.spring.boot.jdbc.dao.IUserDao;
import com.jege.spring.boot.jdbc.entity.User;@RunWith(SpringJUnit4ClassRunner.class)
@SpringBootTest()
public class UserDaoTest {@AutowiredIUserDao userDao;// 每次执行Test之前先删除表，创建表@Beforepublic void before() throws Exception {userDao.dropTable();userDao.createTable();}@Testpublic void save() throws Exception {for (int i = 0; i < 10; i++) {User user = new User("jege" + i, 25 + i);userDao.save(user);}}@Testpublic void all() throws Exception {save();assertThat(userDao.findAll()).hasSize(10);}@Testpublic void findByName() throws Exception {save();assertThat(userDao.findByNameLike("jege%")).hasSize(10);}@Afterpublic void destroy() throws Exception {userDao.deleteAll();}}