Maven - Build & Test Project

What we learnt in Project Creation chapter is how to create a Java application using Maven. Now we'll see how to build and test the application.
Go to C:/MVN directory where you've created your java application. Open consumerBanking folder.You will see the POM.xml file with following contents.

<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>com.companyname.projectgroup</groupId>
      <artifactId>project</artifactId>
      <version>1.0</version>
      <dependencies>
         <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>3.8.1</version>
         </dependency>
      </dependencies>  
</project>

Here you can see, Maven already added Junit as test framework. By default Maven adds a source file App.java and a test file AppTest.java in its default directory structure discussed in previous chapter.
Let's open command console, go the C:\MVN\consumerBanking directory and execute the following mvn command.

C:\MVN\consumerBanking>mvn clean package

Maven will start building the project.

[INFO] Scanning for projects...
[INFO]
[INFO] ------------------------------------------------------------------------
[INFO] Building consumerBanking 1.0-SNAPSHOT
[INFO] ------------------------------------------------------------------------
[INFO]
[INFO] --- maven-clean-plugin:2.5:clean (default-clean) @ consumerBanking ---
[INFO] Deleting C:\MVN\consumerBanking\target
[INFO]
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ consumerBanking ---
[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources,i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory C:\MVN\consumerBanking\src\main\resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ consumerBanking ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding Cp1252, i.e. build is platform dependent!
[INFO] Compiling 1 source file to C:\MVN\consumerBanking\target\classes
[INFO]
[INFO] --- maven-resources-plugin:2.6:testResources (default-testResources) @ consumerBanking ---
[WARNING] Using platform encoding (Cp1252 actually) to copy filtered resources,
i.e. build is platform dependent!
[INFO] skip non existing resourceDirectory C:\MVN\consumerBanking\src\test\resources
[INFO]
[INFO] --- maven-compiler-plugin:3.1:testCompile (default-testCompile) @ consumerBanking ---
[INFO] Changes detected - recompiling the module!
[WARNING] File encoding has not been set, using platform encoding Cp1252, i.e. b
uild is platform dependent!
[INFO] Compiling 1 source file to C:\MVN\consumerBanking\target\test-classes
[INFO]
[INFO] --- maven-surefire-plugin:2.12.4:test (default-test) @ consumerBanking ---
[INFO] Surefire report directory: C:\MVN\consumerBanking\target\surefire-reports


-------------------------------------------------------
 T E S T S
-------------------------------------------------------
Running com.companyname.bank.AppTest
Tests run: 1, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 0.063 sec

Results :

Tests run: 1, Failures: 0, Errors: 0, Skipped: 0

[INFO]
[INFO] --- maven-jar-plugin:2.4:jar (default-jar) @ consumerBanking ---
[INFO] Building jar: C:\MVN\consumerBanking\target\consumerBanking-1.0-SNAPSHOT.jar
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 14.406 s
[INFO] Finished at: 2015-09-27T17:58:06+05:30
[INFO] Final Memory: 14M/247M
[INFO] ------------------------------------------------------------------------

You've built your project and created final jar file, following are the key learning concepts

• We give maven two goals, first to clean the target directory (clean) and then package the project build output as jar(package).
• Packaged jar is available in consumerBanking\target folder as consumerBanking-1.0-SNAPSHOT.jar.
  
• Test reports are available in consumerBanking\target\surefire-reports folder.
  
• Maven compiled source code file(s) and then test source code file(s).
• Then Maven run the test cases.
• Finally Maven created the package.

Now open command console, go the C:\MVN\consumerBanking\target\classes directory and execute the following java command.

C:\MVN\consumerBanking\target\classes>java com.companyname.bank.App

You will see the result

Hello World!

Adding Java Source Files

Let's see how we can add additional Java files in our project. Open C:\MVN\consumerBanking\src\main\java\com\companyname\bank folder, create Util class in it as Util.java.

package com.companyname.bank;

public class Util 
{
   public static void printMessage(String message){
    System.out.println(message);
   }
}

Update App class to use Util class.

package com.companyname.bank;

/**
 * Hello world!
 *
 */
public class App 
{
    public static void main( String[] args )
    {
        Util.printMessage("Hello World!");
    }
}

Now open command console, go the C:\MVN\consumerBanking directory and execute the following mvn command.

C:\MVN\consumerBanking>mvn clean compile

After Maven build is successful, go the C:\MVN\consumerBanking\target\classes directory and execute the following java command.

C:\MVN\consumerBanking\target\classes>java -cp com.companyname.bank.App

You will see the result

Hello World!