前面介绍了 Spring 怎样集成 Druid，下面将通过一个简单示例演示 Druid 和 Spring Boot 集成，然后通过 JdbcTemplate 从 MySQL 5.7.* 中获取数据库时间戳。
Spring Boot 项目的依赖如下：
<?xml version="1.0" encoding="UTF-8"?> <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 https://maven.apache.org/xsd/maven-4.0.0.xsd"> <modelVersion>4.0.0</modelVersion> <parent> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-parent</artifactId> <version>2.7.13</version> <relativePath/> <!-- lookup parent from repository --> </parent> <groupId>com.hxstrive.jdbc_pool</groupId> <artifactId>druid_spring_boot</artifactId> <version>0.0.1-SNAPSHOT</version> <name>druid_spring_boot</name> <description>Demo project for Spring Boot</description> <properties> <java.version>8</java.version> </properties> <dependencies> <!-- https://mvnrepository.com/artifact/com.alibaba/druid --> <dependency> <groupId>com.alibaba</groupId> <artifactId>druid</artifactId> <version>1.2.15</version> </dependency> <!-- MySQL 驱动依赖 --> <dependency> <groupId>mysql</groupId> <artifactId>mysql-connector-java</artifactId> <version>5.1.38</version> </dependency> <!-- Spring Boot JDBC依赖驱动 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-jdbc</artifactId> </dependency> <!-- Spring Boot Web 驱动依赖 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <!-- Spring Boot 开发和测试依赖 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-devtools</artifactId> <scope>runtime</scope> <optional>true</optional> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> <scope>test</scope> </dependency> </dependencies> <build> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> <configuration> <excludes> <exclude> <groupId>org.projectlombok</groupId> <artifactId>lombok</artifactId> </exclude> </excludes> </configuration> </plugin> </plugins> </build> </project>
使用 @Configuration 声明一个配置类，配置 JdbcTemplate 和 DataSource（数据源），代码如下：
package com.hxstrive.pool.druid_spring_boot.config;
import com.alibaba.druid.pool.DruidDataSourceFactory;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.core.JdbcTemplate;
import javax.sql.DataSource;
import java.util.HashMap;
import java.util.Map;
/**
* Druid配置
* @author hxstrive.com
*/
@Configuration
public class DruidConfig {
/**
* 配置 JdbcTemplate
* @param dataSource 数据源
* @return
*/
@Bean
public JdbcTemplate getJdbcTemplate(DataSource dataSource) {
return new JdbcTemplate(dataSource);
}
/**
* 配置数据源
* @return 返回 com.mchange.v2.c3p0.ComboPooledDataSource 数据源
*/
@Bean
public DataSource getDataSource() throws Exception {
Map<String,String> map = new HashMap<String,String>();
map.put("driverClassName", "com.mysql.jdbc.Driver");
map.put("url", "jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf8&useSSL=false");
map.put("username", "root");
map.put("password", "aaaaaa");
// 初始化连接数量
map.put("initialSize", "5");
// 最大连接数
map.put("maxActive", "10");
// 最大等待时间
map.put("maxWait", "3000");
map.put("minIdle", "3");
return DruidDataSourceFactory.createDataSource(map);
}
}Spring Boot 项目的启动类，代码如下：
package com.hxstrive.pool.druid_spring_boot;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class DruidSpringBootApplication {
public static void main(String[] args) {
SpringApplication.run(DruidSpringBootApplication.class, args);
}
}通过 @SpringBootTest 注解声明一个测试类，通过单元测试进行测试，代码如下：
package com.hxstrive.pool.druid_spring_boot;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.jdbc.core.JdbcTemplate;
import java.sql.Timestamp;
@SpringBootTest
class DruidSpringBootApplicationTests {
@Autowired
private JdbcTemplate jdbcTemplate;
@Test
void contextLoads() {
// 获取数据库当前的时间戳
Timestamp ts = jdbcTemplate.queryForObject("select CURRENT_TIMESTAMP() as ct", Timestamp.class);
System.out.println(ts);
}
}运行测试类，输出如下：
... 省略 ...
. ____ _ __ _ _
/\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \
( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \
\\/ ___)| |_)| | | | | || (_| | ) ) ) )
' |____| .__|_| |_|_| |_\__, | / / / /
=========|_|==============|___/=/_/_/_/
:: Spring Boot :: (v2.7.13)
2023-07-11 12:42:44.037 INFO 8296 --- [ main] c.h.p.d.DruidSpringBootApplicationTests : Starting DruidSpringBootApplicationTests using Java 1.8.0_45 on hxstrive with PID 8296 (started by Administrator in D:\~my_workspace\jdbc_pool\druid_spring_boot)
2023-07-11 12:42:44.040 INFO 8296 --- [ main] c.h.p.d.DruidSpringBootApplicationTests : No active profile set, falling back to 1 default profile: "default"
2023-07-11 12:42:49.465 INFO 8296 --- [ main] c.h.p.d.DruidSpringBootApplicationTests : Started DruidSpringBootApplicationTests in 6.406 seconds (JVM running for 11.577)
2023-07-11 12:42:51.004 INFO 8296 --- [ main] com.alibaba.druid.pool.DruidDataSource : {dataSource-1} inited
2023-07-11 12:42:51.0
2023-07-11 12:42:51.093 INFO 8296 --- [ionShutdownHook] com.alibaba.druid.pool.DruidDataSource : {dataSource-1} closing ...
2023-07-11 12:42:51.101 INFO 8296 --- [ionShutdownHook] com.alibaba.druid.pool.DruidDataSource : {dataSource-1} closed
