What is Java?

Java (.java) files contain Java source code designed for platform independence through the Java Virtual Machine (JVM). Created by James Gosling at Sun Microsystems in 1995, Java has become one of the most widely used programming languages in enterprise software, Android apps, and large-scale systems.

Java combines strong typing, object-oriented programming, automatic garbage collection, and rich standard libraries. It's used for everything from Android mobile apps to enterprise backends, big data processing with Hadoop and Spark, and cloud-based microservices.

Did you know? Java was originally called "Oak" and later "Green" before being renamed after coffee from Java, Indonesia!

History

Java was developed at Sun Microsystems by James Gosling and his team. Originally designed for interactive television, it became the foundation of modern enterprise computing after Sun was acquired by Oracle in 2010.

Key Milestones

  • 1995: Java 1.0 released by Sun Microsystems
  • 2004: Java 5 introduced generics and annotations
  • 2010: Oracle acquires Sun Microsystems
  • 2014: Java 8 adds lambdas and streams
  • 2017: Java 9+ with 6-month release cycle
  • Present: Java 21 LTS with virtual threads

Key Features

Core Capabilities

  • Platform Independence: Runs on JVM across all platforms
  • Strong Static Typing: Compile-time type checking
  • Object-Oriented: Classes, inheritance, polymorphism
  • Garbage Collection: Automatic memory management
  • Rich Standard Library: Extensive built-in APIs
  • Multi-Threading: Built-in concurrency support

Common Use Cases

Enterprise Applications

Banking, finance, large-scale systems

Android Development

Mobile apps with Kotlin/Java

Big Data

Hadoop, Spark, Kafka processing

Cloud Services

Microservices with Spring Boot

Advantages

  • Platform independence (JVM)
  • Strong ecosystem and tooling
  • Excellent performance
  • Large talent pool
  • Mature and stable
  • Great for large teams

Disadvantages

  • Verbose syntax
  • Slower startup time
  • More memory consumption
  • Slower development than dynamic languages
  • GUI development less popular
  • Oracle licensing complexities

Technical Information

Format Specifications

Specification Details
File Extension .java
MIME Type text/x-java
Encoding UTF-8
Paradigm Object-Oriented
Compilation Bytecode (.class)
Runtime JVM (Java Virtual Machine)

Common Tools

  • IDEs: IntelliJ IDEA, Eclipse, NetBeans
  • Build Tools: Maven, Gradle
  • Frameworks: Spring, Jakarta EE, Quarkus