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Maven
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=> Maven is a free and open source s/w.

=> Maven tool developed by apache org.

=> Maven developed using Java language.

=> Maven is used to automate java projects build process.

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What is build process ?
========================

1) Download required jars (libraries)

	Ex: spring, springboot, junit, log4j..
	
2) Compile project source code

      .java files -----> .class files 

3) Execute Junit test cases. 

4) Package our application

	Ex : jar file or war file
	
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Maven Setup	
============

@@ Reference Video : https://www.youtube.com/watch?v=hV1OWzYpzxo

1) Download and install java s/w

2) Setup JAVA_HOME and Java Path 
	
	JAVA_HOME=C:\Program Files\Java\jdk-17
	path=C:\Program Files\Java\jdk-17\bin

3) Download Maven sotware as zip and extract it

4) Setup MAVEN_HOME and Maven Path 

	MAVEN_HOME = C:\apache-maven-3.9.9
	path=C:\apache-maven-3.9.9\bin
	
5)  Verify Maven setup in command prompt	

	  $ mvn -version
	  
==================
Maven Terminology
==================

Archetype : Represents type of project

		quick-start : console app

		web-app : web application

groupId : Represents company name

	Ex : com.tcs
		 com.ibm
		 in.ashokit

ArtifactId : Represents project name

Version : Represents project version
	
		SNAPSHOT : under development

		RELEASE : Delivered to client		 	


Dependencies : Represents libraries required for project

 Ex : spring, spring-boot, hibernate, junit, lombok..


Maven Repositories : Represents the location of maven dependencies

		1) Central (public)
		2) Remote (private -> nexus/jfrog)
		3) Local (.m2)

Maven Goals : Used to perform project build process.		

	clean : delete .class files (target folder)

	compile : convert .java files into .class files

	test : execute junits

	package : generate jar or war

	

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Create Maven Project in CLI
============================

=> Open CmD and execute below command to create maven project

mvn archetype:generate -DgroupId=in.ashokit -DartifactId=my-app -DarchetypeArtifactId=maven-archetype-quickstart -DarchetypeVersion=1.5 -DinteractiveMode=false

=> We can see below folder structure in the maven project

		My-App
			- src/main/java   (source code .java files)
			- src/main/resources (config files)
			- src/test/java (junit classes)
			- src/test/resources (config files for testing)
			- Maven Dependencies (jars)
			- pom.xml (project object model)

=> Go inside maven project and execute maven goals

		cd my-app

		mvn compile
		mvn test
		mvn package
		mvn clean package			


=> Byte code will be generated in project "target" directory.		

=> We can add maven dependencies in "pom.xml" file.

=> We can find maven dependencies in below website

		URL : www.mvnrepository.com	
	  
=========================	  
Maven Project Structure	 
========================= 
	  
===================	  
Maven Dependencies	
===================

=> The jar files required for the application development are called as maven dependencies.  

=> We can find maven dependencies in below website

	URl : https://mvnrepository.com/
	

=> We need to add maven dependencies in project "pom.xml" file then maven will download them and will add to project build path.	

=> When we add dependency in pom.xml file, maven will download child dependencies also. That is called as transitive dependency management.

Ex : when we add "spring-context" dependency maven downloading below dependencies also like below

		a) spring-core
		b) spring-beans
		c) spring-aop
		d) spring-jcl
		e) spring-expression
		
Note: With transitive dependencies we have advantage and dis-advantage also.

	Advantage : less configuration in pom.xml
	
	Dis-Advantage : Unwanted jars also loaded.
	
===============================
What is dependency exclusion ?	
===============================

=> Removing unwanted child dependencies from parent.

=> With below configuration we are excluding "spring-aop" from "spring-context"

<dependency>
	<groupId>org.springframework</groupId>
	<artifactId>spring-context</artifactId>
	<version>6.2.0</version>
	<exclusions>
		<exclusion>
			<groupId>org.springframework</groupId>
			<artifactId>spring-aop</artifactId>
		</exclusion>
	</exclusions>
</dependency>

====================
Maven Repository ?
====================

=> Repository is a place where maven dependencies will be stored.

=> Maven will work with 3 types of repositories 

	1) Local Repository
	2) Central repository
	3) Remote Repository	

@@ Local Repository : Where maven will store dependencies in our system (.m2 folder).

Central Repository : Apache maintaining all jars here (public repo).

@@ Remote Repository : Private repository maintained for companies. We can use nexus/jfrog to work with remote repositories.

Note-1: Maven will search for dependencies in local repo first if not available in local repo then it will download from central/remote repositories.

Note-2 : If dependencies available in local repo then maven will add from local repo to project build path.


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How to connect with remote repository ?
=========================================

=> Once we join in the project team then we should take "settings.xml" file from the team members.

=> Inside "settings.xml" file remote repo details will be configured.

	Repo Server URL :
	Repo Server uname:
	Repo Server pwd : 


===========================
What is Dependency scope ?
===========================

=> It represents when to load dependency into project class path 

=> We have below 6 scopes for maven dependency 

1) compile (Default)
2) provided
3) runtime
4) test
5) system
6) import

==============================================================
How to skip unit test execution while packaging application ?
===============================================================

mvn clean package -DskipTests=true


=================
Gradle Tutorial
=================

Gradle Reference Video : https://www.youtube.com/watch?v=I84f9Q5bFBA