Part A: Build and Run a Java Application with Maven

For this part, please refer to Experiment 2: Working with Maven. Follow the steps outlined in Experiment 2 to:

1. Create a Maven project (HelloMaven).

mvn archetype:generate -DgroupId=com.example -DartifactId=HelloMaven -DarchetypeArtifactId=maven-archetype-quickstart -DinteractiveMode=false

1. Navigate into the project directory.
2. Explore the project structure.
3. Build the project using mvn package.
4. Run the application using the java -cp

Ensure you have successfully built and run the HelloMaven project using Maven before proceeding to Part B.

Part B: Migrate the Application to Gradle (In-Place)

• Step 1: Ensure You Are in the Maven Project Directory

  Make sure your current directory in the terminal is the root of your Maven project (HelloMaven).

• Step 2: Initialize Gradle in the Existing Maven Project

  Run the gradle init command. Gradle will detect the existing project structure and attempt to generate appropriate build files. Select Groovy DSL.

  gradle init
  

  

• Step 3: Explore the Updated Project Structure After running gradle init, new files and directories will be added to your HelloMaven folder, including gradlew, gradlew.bat, settings.gradle, and potentially a build.gradle (or build.gradle.kts) file in the root or within a subfolder like app (depending on how gradle init interpreted your project). Use the tree command again to see the changes:

  tree
  

  

• Step 4: Understand and Update the Generated Gradle Build Script Gradle has generated a build script.

  Open the build.gradle file using command:

  gedit build.gradle
  

  Replace the entire content of the generated build script with the appropriate example below. The example here is configured to use JUnit 4 and correctly point the application plugin to the com.example.App class. Without application plugin gradle run will not work.

  Groovy DSL (build.gradle):

  /*
   * This file was generated by the Gradle 'init' task.
   * Modified for Experiment 4 to enable 'gradle run' for an application.
   */
  
  plugins {
      // Use the application plugin to add support for building and running a Java application
      id 'application'
      id 'java-library' 
      id 'maven-publish' 
  }
  
  repositories {
      mavenLocal()
      maven {
          url = uri('<https://repo.maven.apache.org/maven2/>')
      }
  }
  
  dependencies {
      // Use JUnit 4 for testing.
      testImplementation libs.junit.junit
  
      // Add any other dependencies from your pom.xml here if needed
      // Example: implementation 'com.otherlibrary:other-library:1.0'
  }
  
  group = 'com.example'
  version = '1.0-SNAPSHOT'
  description = 'HelloMaven'
  java.sourceCompatibility = JavaVersion.VERSION_1_8 // Or a higher version if needed
  
  // Define the main class for the application.
  // This is required by the 'application' plugin to run the application.
  application {
      mainClass = 'com.example.App' // Make sure this matches the package and class name of your App.java
  }
  
  // The publishing block is for publishing the library - not needed for 'gradle run'
  // Keep or remove based on your project's full requirements.
  publishing {
      publications {
          maven(MavenPublication) {
              from(components.java)
          }
      }
  }
  
  // You can add other tasks or configurations here as needed
  

  Save the changes to the build script.