方式一：使用springBoot 自动配置数据源
生成项目添加依赖
- H2
- JDBC
- Lombok
- Web
- Actuator 健康检查
application.properties 数据源相关属性
# actuator 配置，可查看注入的bean
management.endpoints.web.exposure.include=*
spring.output.ansi.enabled=ALWAYS
spring.datasource.url=jdbc:h2:mem:testdb
spring.datasource.username=sa
spring.datasource.password=
spring.datasource.hikari.maximumPoolSize=5
spring.datasource.hikari.minimumIdle=5
spring.datasource.hikari.idleTimeout=600000
spring.datasource.hikari.connectionTimeout=30000
spring.datasource.hikari.maxLifetime=1800000
打印 数据源
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.jdbc.core.JdbcTemplate;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;
@SpringBootApplication
@Slf4j
public class DatasourceDemoApplication implements CommandLineRunner {
@Autowired
private DataSource dataSource;
@Autowired
private JdbcTemplate jdbcTemplate;
public static void main(String[] args) {
SpringApplication.run(DatasourceDemoApplication.class, args);
}
@Override
public void run(String... args) throws Exception {
showConnection();
showData();
}
private void showConnection() throws SQLException {
log.info(dataSource.toString());
Connection conn = dataSource.getConnection();
log.info(conn.toString());
conn.close();
}
private void showData() {
jdbcTemplate.queryForList("SELECT * FROM FOO")
.forEach(row -> log.info(row.toString()));
}
}
查看beans
http://localhost:8080/actuator/beans
设置初始化数据
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- data.sql
INSERT INTO FOO (ID, BAR) VALUES (1, 'aaa');
INSERT INTO FOO (ID, BAR) VALUES (2, 'bbb');
- schema.sql
CREATE TABLE FOO (ID INT IDENTITY, BAR VARCHAR(64));
springboot与数据源相关配置
image.png
方式二：手动配置数据源
image.png
依赖引入
<?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 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>geektime.spring.data</groupId>
<artifactId>pure-spring-datasource-demo</artifactId>
<version>1.0-SNAPSHOT</version>
<properties>
<spring.version>5.1.3.RELEASE</spring.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-context</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.springframework</groupId>
<artifactId>spring-jdbc</artifactId>
<version>${spring.version}</version>
</dependency>
<dependency>
<groupId>org.apache.commons</groupId>
<artifactId>commons-dbcp2</artifactId>
<version>RELEASE</version>
</dependency>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<version>RELEASE</version>
<scope>runtime</scope>
</dependency>
</dependencies>
</project>
使用原生方法打印数据源
import org.apache.commons.dbcp2.BasicDataSourceFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.context.ApplicationContext;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.support.ClassPathXmlApplicationContext;
import org.springframework.jdbc.datasource.DataSourceTransactionManager;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import javax.sql.DataSource;
import java.sql.Connection;
import java.sql.SQLException;
import java.util.Arrays;
import java.util.Properties;
@Configuration
@EnableTransactionManagement
public class DataSourceDemo {
@Autowired
private DataSource dataSource;
public static void main(String[] args) throws SQLException {
ApplicationContext applicationContext =
new ClassPathXmlApplicationContext("applicationContext*.xml");
showBeans(applicationContext);
dataSourceDemo(applicationContext);
}
@Bean(destroyMethod = "close")
public DataSource dataSource() throws Exception {
Properties properties = new Properties();
properties.setProperty("driverClassName", "org.h2.Driver");
properties.setProperty("url", "jdbc:h2:mem:testdb");
properties.setProperty("username", "sa");
return BasicDataSourceFactory.createDataSource(properties);
}
@Bean
public PlatformTransactionManager transactionManager() throws Exception {
return new DataSourceTransactionManager(dataSource());
}
private static void showBeans(ApplicationContext applicationContext) {
System.out.println(Arrays.toString(applicationContext.getBeanDefinitionNames()));
}
private static void dataSourceDemo(ApplicationContext applicationContext) throws SQLException {
DataSourceDemo demo = applicationContext.getBean("dataSourceDemo", DataSourceDemo.class);
demo.showDataSource();
}
public void showDataSource() throws SQLException {
System.out.println(dataSource.toString());
Connection conn = dataSource.getConnection();
System.out.println(conn.toString());
conn.close();
}
}
dataSource 的属性设置，也可以在applicationContext.xml 配置
<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
<context:component-scan base-package="geektime.spring.data" />
<!-- 通过配置的方式注入bean -->
<!--
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource"
destroy-method="close">
<property name="driverClassName" value="org.h2.Driver"/>
<property name="url" value="jdbc:h2:mem:testdb"/>
<property name="username" value="SA"/>
<property name="password" value=""/>
</bean>
-->
</beans>
总结
-
springboot 帮助我们干什么
相关自动配置
ps: bean都是按需索取的：代码中已经已经的配置的bean，不会重复配置。
