DataSource 예제 - DriverManager

DataSource 예제인 DriverManager를 만들어보자.

 

실제 커넥션을 각각 가져와 준다.

 

package hello.jdbc.connection;


import lombok.extern.slf4j.Slf4j;
import org.junit.jupiter.api.Test;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;

import static hello.jdbc.connection.ConnectionConst.*;

@Slf4j
public class ConnectionTest {

    @Test
    void driverManager() throws SQLException {
        Connection con1 = DriverManager.getConnection(URL, USERNAME, PASSWORD);
        Connection con2 = DriverManager.getConnection(URL, USERNAME, PASSWORD);
        log.info("connection={}, class={}", con1, con1.getClass());
        log.info("connection={}, class={}", con2, con2.getClass());
    }
}

"/Applications/IntelliJ IDEA CE.app/Contents/jbr/Contents/Home/bin/java" -ea -Didea.test.cyclic.buffer.size=1048576 -javaagent:/Applications/IntelliJ IDEA CE.app/Contents/lib/idea_rt.jar=64856:/Applications/IntelliJ IDEA CE.app/Contents/bin -Dfile.encoding=UTF-8 -classpath /Users/milaju/.m2/repository/org/junit/platform/junit-platform-launcher/1.8.2/junit-platform-launcher-1.8.2.jar:/Users/milaju/.m2/repository/org/junit/platform/junit-platform-engine/1.8.2/junit-platform-engine-1.8.2.jar:/Users/milaju/.m2/repository/org/opentest4j/opentest4j/1.2.0/opentest4j-1.2.0.jar:/Users/milaju/.m2/repository/org/junit/platform/junit-platform-commons/1.8.2/junit-platform-commons-1.8.2.jar:/Users/milaju/.m2/repository/org/apiguardian/apiguardian-api/1.1.2/apiguardian-api-1.1.2.jar:/Applications/IntelliJ IDEA CE.app/Contents/lib/idea_rt.jar:/Applications/IntelliJ IDEA CE.app/Contents/plugins/junit/lib/junit5-rt.jar:/Applications/IntelliJ IDEA CE.app/Contents/plugins/junit/lib/junit-rt.jar:/Users/milaju/Desktop/SpringDB1/jdbcStudy/out/test/classes:/Users/milaju/Desktop/SpringDB1/jdbcStudy/out/production/classes:/Users/milaju/Desktop/SpringDB1/jdbcStudy/out/production/resources:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot-starter-jdbc/2.7.0/dd69f21efd63a2a16d631210b5656dc30348451b/spring-boot-starter-jdbc-2.7.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.projectlombok/lombok/1.18.24/13a394eed5c4f9efb2a6d956e2086f1d81e857d9/lombok-1.18.24.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot-starter-test/2.7.0/417764bfd907f7deffd617fb31b3ea0900547287/spring-boot-starter-test-2.7.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot-starter/2.7.0/64fd3c21486dd20df9a62566599337dae2eb62cc/spring-boot-starter-2.7.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/com.zaxxer/HikariCP/4.0.3/107cbdf0db6780a065f895ae9d8fbf3bb0e1c21f/HikariCP-4.0.3.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework/spring-jdbc/5.3.20/140414df1080754fcefe12921543c599e51dfbb2/spring-jdbc-5.3.20.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot-test-autoconfigure/2.7.0/e0270c5cf20211c43f7b485c64e3e6a96f16b991/spring-boot-test-autoconfigure-2.7.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot-test/2.7.0/8be4bc652e4bd0ae0f61b99e164ae26ac269f154/spring-boot-test-2.7.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/com.jayway.jsonpath/json-path/2.7.0/f9d7d9659f2694e61142046ff8a216c047f263e8/json-path-2.7.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/jakarta.xml.bind/jakarta.xml.bind-api/2.3.3/48e3b9cfc10752fba3521d6511f4165bea951801/jakarta.xml.bind-api-2.3.3.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.assertj/assertj-core/3.22.0/c300c0c6a24559f35fa0bd3a5472dc1edcd0111e/assertj-core-3.22.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.hamcrest/hamcrest/2.2/1820c0968dba3a11a1b30669bb1f01978a91dedc/hamcrest-2.2.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.junit.jupiter/junit-jupiter/5.8.2/5a817b1e63f1217e5c586090c45e681281f097ad/junit-jupiter-5.8.2.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.mockito/mockito-junit-jupiter/4.5.1/f81fb60bd69b3a6e5537ae23b883326f01632a61/mockito-junit-jupiter-4.5.1.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.mockito/mockito-core/4.5.1/ed456e623e5afc6f4cee3ae58144e5c45f3b3bf/mockito-core-4.5.1.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.skyscreamer/jsonassert/1.5.0/6c9d5fe2f59da598d9aefc1cfc6528ff3cf32df3/jsonassert-1.5.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework/spring-test/5.3.20/33a92d5066fb810023969a0d70fac96387962769/spring-test-5.3.20.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework/spring-core/5.3.20/4b88aa3c401ede3d6c8ac78ea0c646cf326ec24b/spring-core-5.3.20.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.xmlunit/xmlunit-core/2.9.0/8959725d90eecfee28acd7110e2bb8460285d876/xmlunit-core-2.9.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot-autoconfigure/2.7.0/483f9a66d0e8326583c5054038d0aa0a95045dc3/spring-boot-autoconfigure-2.7.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot/2.7.0/df8bd106d6c6a6494b787b71d23cef6d2dc73703/spring-boot-2.7.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework.boot/spring-boot-starter-logging/2.7.0/5ff2a55d345ad824f39d55eaa32203865a92b30f/spring-boot-starter-logging-2.7.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/jakarta.annotation/jakarta.annotation-api/1.3.5/59eb84ee0d616332ff44aba065f3888cf002cd2d/jakarta.annotation-api-1.3.5.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.yaml/snakeyaml/1.30/8fde7fe2586328ac3c68db92045e1c8759125000/snakeyaml-1.30.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.slf4j/slf4j-api/1.7.36/6c62681a2f655b49963a5983b8b0950a6120ae14/slf4j-api-1.7.36.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework/spring-tx/5.3.20/9a4ec2249dc3523ac70e0710a64288c14fc3ff78/spring-tx-5.3.20.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework/spring-beans/5.3.20/ab88bd9e3a8307f5c0516c15d295c88ec318659/spring-beans-5.3.20.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/net.minidev/json-smart/2.4.8/7c62f5f72ab05eb54d40e2abf0360a2fe9ea477f/json-smart-2.4.8.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/jakarta.activation/jakarta.activation-api/1.2.2/99f53adba383cb1bf7c3862844488574b559621f/jakarta.activation-api-1.2.2.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.junit.jupiter/junit-jupiter-params/5.8.2/ddeafe92fc263f895bfb73ffeca7fd56e23c2cce/junit-jupiter-params-5.8.2.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.junit.jupiter/junit-jupiter-api/5.8.2/4c21029217adf07e4c0d0c5e192b6bf610c94bdc/junit-jupiter-api-5.8.2.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/net.bytebuddy/byte-buddy/1.12.10/f34127d93639fad8c6fb84b3ca30292697d6c55d/byte-buddy-1.12.10.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/net.bytebuddy/byte-buddy-agent/1.12.10/1f097f8d6cad60e8f93e5eb670cf5dc9b64da32/byte-buddy-agent-1.12.10.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/com.vaadin.external.google/android-json/0.0.20131108.vaadin1/fa26d351fe62a6a17f5cda1287c1c6110dec413f/android-json-0.0.20131108.vaadin1.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework/spring-jcl/5.3.20/35119231d09863699567ce579c21512ddcbc5407/spring-jcl-5.3.20.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework/spring-context/5.3.20/517a42165221ea944c8b794154c10b69c0128281/spring-context-5.3.20.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/ch.qos.logback/logback-classic/1.2.11/4741689214e9d1e8408b206506cbe76d1c6a7d60/logback-classic-1.2.11.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-to-slf4j/2.17.2/17dd0fae2747d9a28c67bc9534108823d2376b46/log4j-to-slf4j-2.17.2.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.slf4j/jul-to-slf4j/1.7.36/ed46d81cef9c412a88caef405b58f93a678ff2ca/jul-to-slf4j-1.7.36.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/net.minidev/accessors-smart/2.4.8/6e1bee5a530caba91893604d6ab41d0edcecca9a/accessors-smart-2.4.8.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.apiguardian/apiguardian-api/1.1.2/a231e0d844d2721b0fa1b238006d15c6ded6842a/apiguardian-api-1.1.2.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.junit.platform/junit-platform-commons/1.8.2/32c8b8617c1342376fd5af2053da6410d8866861/junit-platform-commons-1.8.2.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.opentest4j/opentest4j/1.2.0/28c11eb91f9b6d8e200631d46e20a7f407f2a046/opentest4j-1.2.0.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework/spring-aop/5.3.20/c82f17997ab18ecafa8d08ce34a7c7aa4a04ef9e/spring-aop-5.3.20.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.springframework/spring-expression/5.3.20/20e179f0dfabf0a46428f22c2150c9c4850fd15d/spring-expression-5.3.20.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/ch.qos.logback/logback-core/1.2.11/a01230df5ca5c34540cdaa3ad5efb012f1f1f792/logback-core-1.2.11.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.apache.logging.log4j/log4j-api/2.17.2/f42d6afa111b4dec5d2aea0fe2197240749a4ea6/log4j-api-2.17.2.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.ow2.asm/asm/9.1/a99500cf6eea30535eeac6be73899d048f8d12a8/asm-9.1.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/com.h2database/h2/2.1.212/f3187885395bd0c0e0e83f96641bb630f368ee2f/h2-2.1.212.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.junit.jupiter/junit-jupiter-engine/5.8.2/c598b4328d2f397194d11df3b1648d68d7d990e3/junit-jupiter-engine-5.8.2.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.objenesis/objenesis/3.2/7fadf57620c8b8abdf7519533e5527367cb51f09/objenesis-3.2.jar:/Users/milaju/.gradle/caches/modules-2/files-2.1/org.junit.platform/junit-platform-engine/1.8.2/b737de09f19864bd136805c84df7999a142fec29/junit-platform-engine-1.8.2.jar com.intellij.rt.junit.JUnitStarter -ideVersion5 -junit5 hello.jdbc.connection.ConnectionTest
21:00:34.549 [main] INFO hello.jdbc.connection.ConnectionTest - connection=conn0: url=jdbc:h2:tcp://localhost/~/test user=SA, class=class org.h2.jdbc.JdbcConnection
21:00:34.552 [main] INFO hello.jdbc.connection.ConnectionTest - connection=conn1: url=jdbc:h2:tcp://localhost/~/test user=SA, class=class org.h2.jdbc.JdbcConnection

Process finished with exit code 0

 

 

 

 

DrivetManager DataSource를 써보자.

@Test
    void dataSourceDriverManager() throws SQLException {
        //DriverManagerDataSource - 항상 새로운 커넥션을 획득
        DriverManagerDataSource dataSource = new DriverManagerDataSource(URL, USERNAME, PASSWORD);
        useDataSource(dataSource);
    }

    private void useDataSource(DataSource dataSource) throws SQLException {
        Connection con1 = dataSource.getConnection();
        Connection con2 = dataSource.getConnection();
        log.info("connection={}, class={}", con1, con1.getClass());
        log.info("connection={}, class={}", con2, con2.getClass());
    }

21:06:27.661 [main] INFO hello.jdbc.connection.ConnectionTest - connection=conn0: url=jdbc:h2:tcp://localhost/~/test user=SA, class=class org.h2.jdbc.JdbcConnection
21:06:27.664 [main] INFO hello.jdbc.connection.ConnectionTest - connection=conn1: url=jdbc:h2:tcp://localhost/~/test user=SA, class=class org.h2.jdbc.JdbcConnection

 

 

 

 

 

파라미터 차이

• 기존 DriverManager를 통해서 커넥션을 획득하는 방법과 DataSource를 통해서 커넥션을 획득하는 방법에는 큰 차이가 있다.

 

DriverManager

DriverManager.getConnection(URL, USERNAME, PASSWORD)
DriverManager.getConnection(URL, USERNAME, PASSWORD)

 

DataSource에서는 getConnection만 쓰면 된다.

void dataSourceDriverManager() throws SQLException {
DriverManagerDataSource dataSource = new DriverManagerDataSource(URL,
USERNAME, PASSWORD);
useDataSource(dataSource);
}
private void useDataSource(DataSource dataSource) throws SQLException {
Connection con1 = dataSource.getConnection();
Connection con2 = dataSource.getConnection();
log.info("connection={}, class={}", con1, con1.getClass());
log.info("connection={}, class={}", con2, con2.getClass());
}

• DriverManager 는 커넥션을 획득할 때 마다 URL , USERNAME , PASSWORD 같은 파라미터를 계속
  전달해야 한다. 

 

• 반면에 DataSource 를 사용하는 방식은 처음 객체를 생성할 때만 필요한 파리미터를
  넘겨두고,  커넥션을 획득할 때는 단순히 dataSource.getConnection() 만 호출하면 된다.

 

 

설정과 사용의 분리

• 설정 : DataSource를 만들고 필요한 속성들을 사용해서 URL, USERNAME, PASSWORD 같은 부분을 입력하는 것을 말한다.

 

• 설정과 관련된 속성들은 한 곳에 있는 것이 향후 변경에 더 유연하게 대처할 수 있다.

 

• 설정은 신경쓰지 않고, DataSource의 getConnection()만 호출해서 사용하면 된다.

 

• 설정과 사용의 분리 설명

 

• 이 부분이 작아보이지만 큰 차이를 만들어내는데, 필요한 데이터를 DataSource 가 만들어지는 시점에
  미리 다 넣어두게 되면,  DataSource 를 사용하는 곳에서는 dataSource.getConnection() 만 호출하면 되므로, URL , USERNAME , PASSWORD 같은 속성들에 의존하지 않아도 된다. 

 

• 그냥 DataSource만 주입받아서 getConnection() 만 호출하면 된다. 쉽게 이야기해서 리포지토리(Repository)는 DataSource 만 의존하고, 이런 속성을 몰라도 된다.

 

• 애플리케이션을 개발해보면 보통 설정은 한 곳에서 하지만, 사용은 수 많은 곳에서 하게 된다.
  덕분에 객체를 설정하는 부분과, 사용하는 부분을 좀 더 명확하게 분리할 수 있다.

 

 

 

 

 

 

 

 

 

 

<출처 김영한: 스프링 DB 1편 - 데이터 접근 핵심 원리>

https://www.inflearn.com/course/%EC%8A%A4%ED%94%84%EB%A7%81-db-1/dashboard

스프링 DB 1편 - 데이터 접근 핵심 원리 - 인프런 | 강의