Archives in Java Deployment

Archives play a crucial role in deploying Java applications efficiently. They package application components into compressed files, making deployment easier and more organized. Java uses a standard compression algorithm for these archives.

The jar.exe utility helps package different types of archives, including:

• JAR (Java Archive): Used for packaging Java libraries and applications.
• WAR (Web Application Archive): Designed for web applications.
• EAR (Enterprise Application Archive): Suitable for large enterprise applications with multiple modules.

Each of these archives functions similarly to ZIP files but follows specific structures and conventions for Java applications.

Creating Archives

Build tools like Maven, Gradle, and Ant automate the creation of JAR, WAR, and EAR files.

WAR (Web Application Archive)

WAR files package Java web applications, containing all necessary resources to run on a web server.

• Abbreviation: WAR (Web Application Archive)
• APIs Used: Servlet API, Java EE API
• Contents: Compiled code, images, HTML, property files (.ppty)
• Deployment Target: Web application servers (e.g., Apache Tomcat)
• Deployment Descriptor: web.xml (inside the WEB-INF folder)

EAR (Enterprise Application Archive)

EAR files are designed for large-scale enterprise applications that require multiple modules. They bundle various Java components together, including WAR files, JAR files, and other resources.

• Abbreviation: EAR (Enterprise Application Archive)
• APIs Used: Java EE API
• Contents: WAR files, RAR files, EJB-JAR files, JAR files
• Deployment Target: Enterprise servers (e.g., JBoss, WebSphere)
• Deployment Descriptor: application.xml (inside the META-INF folder)