Maven - Simple Project Build

-

 


Apache Maven is a software project management and comprehension tool. Based on the concept of a project object model (POM), Maven can manage a project's build, reporting and documentation from a central piece of information.

You need somewhere for your project to reside. Create a directory somewhere and start a shell in that directory. On your command line, execute the following Maven goal:

mvn archetype:generate -DgroupId=com.mycompany.app -DartifactId=my-app -DarchetypeArtifactId=maven-archetype-quickstart -DarchetypeVersion=1.4 -DinteractiveMode=false

Executing this command for first time will take time to complete as it downloads dependents .jar file.
[INFO] ----------------------------------------------------------------------------
[INFO] Using following parameters for creating project from Archetype: maven-archetype-quickstart:1.4
[INFO] ----------------------------------------------------------------------------
[INFO] Parameter: groupId, Value: com.mycompany.app
[INFO] Parameter: artifactId, Value: my-app
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Parameter: package, Value: com.mycompany.app
[INFO] Parameter: packageInPathFormat, Value: com/mycompany/app
[INFO] Parameter: package, Value: com.mycompany.app
[INFO] Parameter: groupId, Value: com.mycompany.app
[INFO] Parameter: artifactId, Value: my-app
[INFO] Parameter: version, Value: 1.0-SNAPSHOT
[INFO] Project created from Archetype in dir: /maven/my-app
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  01:06 min
[INFO] Finished at: 2022-08-09T19:35:09-07:00
[INFO] ------------------------------------------------------------------------
root@jenkins:/maven#
root@jenkins:/maven#

Here is the directory structure created post command execution.

root@jenkins:/maven# tree
.
└── my-app -> DartifactId
    ├── pom.xml
    └── src
        ├── main
        │   └── java
        │       └── com
        │           └── mycompany
        │               └── app
        │                   └── App.java
        └── test
            └── java
                └── com
                    └── mycompany
                        └── app
                            └── AppTest.java

12 directories, 3 files
root@jenkins:/maven#

The src/main/java directory contains the project source code, the src/test/java directory contains the test source, and the pom.xml file is the project's Project Object Model, or POM.

The pom.xml file is the core of a project's configuration in Maven. 

It is a single configuration file that contains the majority of information required to build a project in just the way you want. 

Lets see our code App.java

root@jenkins:/maven# cd my-app/src/main/java/com/mycompany/app/
root@jenkins:/maven/my-app/src/main/java/com/mycompany/app# cat App.java
package com.mycompany.app;

/**
 * Hello world!
 *
 */
public class App
{
    public static void main( String[] args )
    {
        System.out.println( "Hello World!" );
    }
}
root@jenkins:/maven/my-app/src/main/java/com/mycompany/app#

Build the Project:

mvn package : Should be executed from the location where you have pom.xml.

root@jenkins:/maven/my-app# ls -l
total 8
-rw-r--r-- 1 root root 2653 Aug  9 19:35 pom.xml
drwxr-xr-x 4 root root 4096 Aug  9 19:35 src
root@jenkins:/maven/my-app# 

This command goes through various steps:

[INFO] Scanning for projects...
[INFO]
[INFO] ----------------------< com.mycompany.app:my-app >----------------------
[INFO] Building my-app 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------


[INFO] --- maven-compiler-plugin:3.8.0:compile (default-compile) @ my-app ---

[INFO] --- maven-surefire-plugin:2.22.1:test (default-test) @ my-app ---

[INFO] --- maven-jar-plugin:3.0.2:jar (default-jar) @ my-app ---

[INFO] Building jar: /maven/my-app/target/my-app-1.0-SNAPSHOT.jar
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  40.086 s
[INFO] Finished at: 2022-08-09T19:56:14-07:00
[INFO] ------------------------------------------------------------------------
root@jenkins:/maven/my-app#

Finally this command compile, test ad build .java code to .jar file.

Maven executes every phase in the sequence up to and including the one defined. For example, if you execute the compile phase, the phases that actually get executed are:

validate
generate-sources
process-sources
generate-resources
process-resources
compile

You may test the newly compiled and packaged JAR with the following command:

java -cp target/my-app-1.0-SNAPSHOT.jar com.mycompany.app.App

root@jenkins:/maven/my-app# java -cp target/my-app-1.0-SNAPSHOT.jar com.mycompany.app.App
Hello World!
root@jenkins:/maven/my-app#

Maven Phases:

Although hardly a comprehensive list, these are the most common default lifecycle phases executed.

validate: validate the project is correct and all necessary information is available
compile: compile the source code of the project
test: test the compiled source code using a suitable unit testing framework. These tests should not require the code be packaged or deployed
package: take the compiled code and package it in its distributable format, such as a JAR.
integration-test: process and deploy the package if necessary into an environment where integration tests can be run
verify: run any checks to verify the package is valid and meets quality criteria
install: install the package into the local repository, for use as a dependency in other projects locally
deploy: done in an integration or release environment, copies the final package to the remote repository for sharing with other developers and projects.

There are two other Maven lifecycles of note beyond the default list above. They are

clean: cleans up artifacts created by prior builds
site: generates site documentation for this project

Cleanup the project.

root@jenkins:/maven/my-app# mvn clean
[INFO] Scanning for projects...
[INFO]
[INFO] ----------------------< com.mycompany.app:my-app >----------------------
[INFO] Building my-app 1.0-SNAPSHOT
[INFO] --------------------------------[ jar ]---------------------------------
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-clean-plugin/3.1.0/maven-clean-plugin-3.1.0.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-clean-plugin/3.1.0/maven-clean-plugin-3.1.0.pom (5.2 kB at 775 B/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-plugins/31/maven-plugins-31.pom
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-plugins/31/maven-plugins-31.pom (10 kB at 80 kB/s)
Downloading from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-clean-plugin/3.1.0/maven-clean-plugin-3.1.0.jar
Downloaded from central: https://repo.maven.apache.org/maven2/org/apache/maven/plugins/maven-clean-plugin/3.1.0/maven-clean-plugin-3.1.0.jar (30 kB at 201 kB/s)
[INFO]
[INFO] --- maven-clean-plugin:3.1.0:clean (default-clean) @ my-app ---
[INFO] Deleting /maven/my-app/target
[INFO] ------------------------------------------------------------------------
[INFO] BUILD SUCCESS
[INFO] ------------------------------------------------------------------------
[INFO] Total time:  11.127 s
[INFO] Finished at: 2022-08-09T20:01:10-07:00
[INFO] ------------------------------------------------------------------------
root@jenkins:/maven/my-app#

Post cleaning:

root@jenkins:/maven/my-app# tree
.
├── pom.xml
└── src
    ├── main
    │   └── java
    │       └── com
    │           └── mycompany
    │               └── app
    │                   └── App.java
    └── test
        └── java
            └── com
                └── mycompany
                    └── app
                        └── AppTest.java

11 directories, 3 files
root@jenkins:/maven/my-app#

Comments

Post a Comment

Popular posts from this blog

SRE/DevOps Syllabus

-
Image
  DEVOPS/SRE Principles. Git What is Git? Architecture of Git. Working principle of Git. Create and cloning a repo. Version control branching. Version control commit. Version control managing workflows. Git hooks. Git Reflog. Git Stash. Git Cherry Picking. Undoing changes in different states of Git. Git based terraform template management. AWS CI/CD SDLC Automation. Code Commit. Code Build. Code Deployment. Code Pipeline. Elastic Beankstalk. Code Artifact. CodeGuru. Terraform Terraform Basics. Terraform State. Working with Terraform. Terraform with AWS. Remote State. Terraform Provisioners. Terraform Import, Tainting and Debugging. Terraform Modules. Terraform Functions and Conditional Expressions. Automation using Python - AWS AWS lambda. Automating EC2 with Lambda. Automating S3 with Lambda. Automating VPC with Lambda. Cost optimization with Lambda. SNS,SQS and SES with Python. Managing and Automating AWS Security with Python. Kubernetes - CKAD Application Developer. Kubernetes A...
Read more

AWS Code Commit - CI/CD Series Part 1

-
Image
  This is a multi-part series to show how to implement a CI/CD pipeline in AWS. In this post, We will see how to use AWS Code Commit. AWS CodeCommit is a fully managed source control service that allows you to store and manage your code securely in the cloud.  It provides a private Git repository for your code and supports all Git commands and workflows. CodeCommit also integrates with other AWS services like AWS CodePipeline and AWS CodeBuild, allowing you to automate your entire software release process. This can help you streamline your development workflows and improve the overall efficiency of your team. I created a repo from AWS CodeCommit -> Create Repository. And I begin with cloning the repo locally. So that I can make changes and push it. To clone the repo click on "HTTPS" under Clone URL. I make changes to index.html file. Now push it to AWS CodeCommit. Let’s verify the changes in AWS Code commit. Changes are reflected in AWS CodeCommit. We are done with Part ...
Read more

Docker - Preventing IP overlapping

-
Image
  What is IP address overlapping? When the container IP address overlaps with another IP external, then the application running on the container is not accessible from outside due to the IP address overlapping.  NOTE: This IP address overlapping can happen on the bridge interface IP or docker container IP. Let's see how to address this IP overlapping issue on the bridge interface. I already have a running container.  root@demo:~# docker run -d --name web --network mynet1 nginx:alpine 268647e11011d513d2357ce1c81e0f48787038a83d01d028d31a5b29dbdb885b root@demo:~# docker container ls CONTAINER ID   IMAGE          COMMAND                  CREATED         STATUS         PORTS     NAMES 268647e11011   nginx:alpine   "/docker-entrypoint.…"   4 seconds ago   Up 3 seconds   80/tcp  ...
Read more