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
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