前面介绍了 Spring 怎样集成 DBCP，下面将通过一个简单示例演示 DBCP 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>dbcp_spring_boot</artifactId> <version>0.0.1-SNAPSHOT</version> <name>dbcp_spring_boot</name> <description>Demo project for Spring Boot</description> <properties> <java.version>8</java.version> </properties> <dependencies> <!-- https://mvnrepository.com/artifact/org.apache.commons/commons-dbcp2 --> <dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-dbcp2</artifactId> <version>2.9.0</version> </dependency> <dependency> <groupId>commons-logging</groupId> <artifactId>commons-logging</artifactId> <version>1.2</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.dbcp_spring_boot.config;
import org.apache.commons.dbcp2.BasicDataSource;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.jdbc.core.JdbcTemplate;
import javax.sql.DataSource;
/**
* DBCP配置
* @author hxstrive.com
*/
@Configuration
public class DbcpConfig {
/**
* 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 org.apache.commons.dbcp2.BasicDataSource 数据源
*/
@Bean
public DataSource getDataSource() {
BasicDataSource dataSource = new BasicDataSource();
dataSource.setDriverClassName("com.mysql.jdbc.Driver");
dataSource.setUrl("jdbc:mysql://localhost:3306/test?useUnicode=true&characterEncoding=utf8&useSSL=false");
dataSource.setUsername("root");
dataSource.setPassword("aaaaaa");
// 初始化时连接池中connection数量
dataSource.setInitialSize(10);
// 最小的空闲链接数量
dataSource.setMinIdle(5);
// 最大的空闲连接数量
dataSource.setMaxIdle(20);
// 最大的等待时间，单位是毫秒
dataSource.setMaxWaitMillis(60000);
// 是否开启自动提交，跟事务的控制有关
dataSource.setDefaultAutoCommit(true);
return dataSource;
}
}Spring Boot 项目的启动类，代码如下：
package com.hxstrive.pool.dbcp_spring_boot;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
@SpringBootApplication
public class DbcpSpringBootApplication {
public static void main(String[] args) {
SpringApplication.run(DbcpSpringBootApplication.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.dbcp_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 DbcpSpringBootApplicationTests {
@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("当前时间：" + ts);
}
}运行测试类，输出如下：
... 省略 ... . ____ _ __ _ _ /\\ / ___'_ __ _ _(_)_ __ __ _ \ \ \ \ ( ( )\___ | '_ | '_| | '_ \/ _` | \ \ \ \ \\/ ___)| |_)| | | | | || (_| | ) ) ) ) ' |____| .__|_| |_|_| |_\__, | / / / / =========|_|==============|___/=/_/_/_/ :: Spring Boot :: (v2.7.13) 2023-07-06 13:21:37.360 INFO 16968 --- [ main] c.h.p.d.DbcpSpringBootApplicationTests : Starting DbcpSpringBootApplicationTests using Java 1.8.0_45 on hxstrive with PID 16968 (started by Administrator in D:\~my_workspace\jdbc_pool\dbcp_spring_boot) 2023-07-06 13:21:37.364 INFO 16968 --- [ main] c.h.p.d.DbcpSpringBootApplicationTests : No active profile set, falling back to 1 default profile: "default" 2023-07-06 13:21:42.400 INFO 16968 --- [ main] c.h.p.d.DbcpSpringBootApplicationTests : Started DbcpSpringBootApplicationTests in 5.848 seconds (JVM running for 9.541) 当前时间：2023-07-06 13:21:43.0 Process finished with exit code 0
