Maven 의존성 관리 기능 및 3rd party lib 이용한 샘플 Java 수정하기

아래에서는 Maven에서 제공하는 의존성관리의 편리함을 활용합니다.

1. 특정 라이브러리에서 제공하는 클래스를 사용하도록 소스를 변경합니다.

C:\Users\kdyoung\myapp\MyMavenTest\src\main\java\org\samples\java\App.java
---------------------------------------------------------------------------------------------------------

package org.samples.java;

import org.slf4j.*;

/**
 * Hello world!
 *
 */
public class App
{
    public static void main( String[] args )
    {
        //System.out.println( "Hello World!" );
Logger logger = LoggerFactory.getLogger(App.class);
logger.info( "Hello World!" );
    }
}

---------------------------------------------------------------------------------------------------------

2. 소스 컴파일을 시도합니다.

-> C:\Users\kdyoung\myapp\MyMavenTest>mvn compile

[INFO] Compiling 1 source file to C:\Users\kdyoung\myapp\MyMavenTest\target\clas
ses
[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR :
[INFO] -------------------------------------------------------------
[ERROR] C:\Users\kdyoung\myapp\MyMavenTest\src\main\java\org\samples\java\App.java:[3,0] package org.slf4j does not exist
[ERROR] C:\Users\kdyoung\myapp\MyMavenTest\src\main\java\org\samples\java\App.java:[14,2] cannot find symbol
symbol  : class Logger
location: class org.samples.java.App
[ERROR] C:\Users\kdyoung\myapp\MyMavenTest\src\main\java\org\samples\java\App.java:[14,18] cannot find symbol
symbol  : variable LoggerFactory
location: class org.samples.java.App
[INFO] 3 errors
[INFO] -------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------


3. pom.xml을 수정하여 dependency를 추가합니다.

Maven Repository Search 사이트중 하나(예, http://mvnrepository.com/)로 이동하여  "slf4j"를 검색하고 slf4j API Module 링크로 이동합니다.

결과 중 하나를 선택하여 클릭합니다.

상세 내용에서 Maven관련 정보를 Copy합니다.

복사한 내용을 pom.xml에 붙여넣기를 합니다.

C:\Users\kdyoung\myapp\MyMavenTest\pom.xml
---------------------------------------------------------------------------------------------------------

<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>org.samples.java</groupId>
  <artifactId>MyMavenTest</artifactId>
  <version>1.0-SNAPSHOT</version>
  <packaging>jar</packaging>

  <name>MyMavenTest</name>
  <url>http://maven.apache.org</url>

  <properties>
    <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
  </properties>

  <dependencies>
    <dependency>
      <groupId>junit</groupId>
      <artifactId>junit</artifactId>
      <version>3.8.1</version>
      <scope>test</scope>
    </dependency>
<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version>
</dependency>
  </dependencies>
</project>

---------------------------------------------------------------------------------------------------------

junit과 달리 scope를 지정하지 않으면 디폴트로 compile 단계로 scope이 지정됩니다.

<dependency>
<groupId>org.slf4j</groupId>
<artifactId>slf4j-api</artifactId>
<version>1.7.5</version> <scope>compile</scope>
</dependency>

4. 소스 컴파일을 합니다.

-> C:\Users\kdyoung\myapp\MyMavenTest>mvn compile

[INFO] ------------------------------------------------------------------------
[INFO] Building MyMavenTest 1.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
Downloading: http://repo.maven.apache.org/maven2/org/slf4j/slf4j-api/1.7.5/slf4j-api-1.7.5.pom
Downloaded: http://repo.maven.apache.org/maven2/org/slf4j/slf4j-api/1.7.5/slf4j-api-1.7.5.pom (3 KB at 1.3 KB/sec)
Downloading: http://repo.maven.apache.org/maven2/org/slf4j/slf4j-parent/1.7.5/slf4j-parent-1.7.5.pom
Downloaded: http://repo.maven.apache.org/maven2/org/slf4j/slf4j-parent/1.7.5/slf4j-parent-1.7.5.pom (12 KB at 28.8 KB/sec)
Downloading: http://repo.maven.apache.org/maven2/org/slf4j/slf4j-api/1.7.5/slf4j-api-1.7.5.jar
Downloaded: http://repo.maven.apache.org/maven2/org/slf4j/slf4j-api/1.7.5/slf4j-api-1.7.5.jar (26 KB at 44.6 KB/sec)

[INFO] Compiling 1 source file to C:\Users\kdyoung\myapp\MyMavenTest\target\classes
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------


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