Devops


Maven

  • Maven is an Open Source, Java-based build tool and developed by Apache.
  • Maven is a powerful project management tool that is based on POM (project object model). 
  • It is used for project build, dependency, and documentation.

Different build tools:

Java         -> ANT/Maveen/Gradle
.Net          -> Nant/MS Build
Python     -> PyBuilder
Ruby        -> Rake


Using Jave can be developed 3 different types of applications:

a) Standalone Applications:

Types of packages: jar (Java Archive)

Examples:
.java 
.class
.jar

b) Web Applications

Types of packages: war (Web Archive)

Examples:
Java Code + Web content (Html, CSS, JS, Images) - static contents

c) Enterprise Applications

Types of packages: ear (Enterprise Archive)

Examples:


How to run the java class "welcome.java"?

Step-1: compile the .java file using javac
javac welcome.java
.jav files are human-readable format and it's a source code file
Step-2: Once you compile it creates a .class file
welcome.class 
.class files are not human-readable format and it's is a byte code. JVM can understand the byte code file. 
Step-3: run the .class file
java welcome      ---- .class extension is not required which executing 


How to run the jar file?
java -jar jarfile_name


When are we going to develop the Enterprise application? 
If the application is a big application like a banking application. Because Enterprise application has multiple modules.



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