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Java is a portable, object-oriented language whose source code is compiled into JVM bytecode.
Java is a high-level, general-purpose, statically and strongly typed programming language designed by James Gosling at Sun Microsystems and first released in 1995. It supports object-oriented, generic, functional, imperative, concurrent, and reflective programming. Java was designed around the principle of “write once, run anywhere” (WORA): source code is compiled into platform-independent JVM bytecode that can run on any system with a compatible Java Virtual Machine. Its syntax resembles C and C++, while providing fewer low-level features, automatic memory management, strong type safety, and built-in security mechanisms. Java applications run through the Java platform, which includes the JVM, standard libraries, and development tools. The JVM translates or just-in-time compiles bytecode into native machine instructions, improving portability while providing competitive performance. Java uses garbage collection to reclaim unused memory and supports reflection, multithreading, networking, graphical user interfaces, enterprise applications, and web technologies. Major platform editions include Java SE, Jakarta EE, Java ME, Java Card, and JavaFX. Java has evolved through many releases, with Java 8, 11, 17, 21, and 25 identified as long-term-support versions in the provided content, and Java 27 listed as the current release as of October 2026.
Java is a portable, object-oriented language whose source code is compiled into JVM bytecode.
The WORA model allows compiled Java programs to run on different hardware and operating systems without recompilation.
The JVM provides runtime services such as bytecode execution, just-in-time compilation, reflection, threading, and platform integration.
Java uses automatic garbage collection and does not support direct pointer arithmetic, improving safety and simplifying memory management.
Java originated at Sun Microsystems, was later stewarded by Oracle, and has substantial open-source development through OpenJDK.
Java supports multiple editions and technologies, including Java SE, Jakarta EE, Java ME, Java Card, Swing, and JavaFX.
Important language features include classes, interfaces, generics, exception handling, Javadoc comments, concurrency, and a C/C++-influenced syntax.
A runtime environment that executes Java bytecode and adapts it to the host operating system and hardware.
Platform-independent intermediate code produced by the Java compiler for execution by the JVM.
Java's portability principle that allows compiled programs to run on compatible platforms without recompilation.
Automatic memory management that reclaims storage occupied by objects that are no longer reachable.
A JVM optimization technique that compiles frequently executed bytecode into native machine code during program execution.
The open-source reference implementation of the Java Development Kit and JVM.
The core Java platform containing the language, standard libraries, JVM tools, and APIs for general-purpose applications.
A Java feature that enables compile-time type checking and reusable classes and methods for different data types.
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