Java Tutorial

Android does not provide the full Java SE standard library, although the Android SDK does include an independent implementation of a large subset of it. The implementation started when Sun began releasing the Java source code under the GPL. OpenJDK is another Java SE implementation that is licensed under the GNU GPL.

Step 2: Verify Installation

J2EE included technologies and APIs for enterprise applications typically run in server environments, while J2ME featured APIs optimized for mobile applications. With the advent of Java 2 (released initially as J2SE 1.2 in December 1998 – 1999), new versions had multiple configurations built for different types of platforms. The Java 1.0 compiler was re-written in Java by Arthur van Hoff to comply strictly with the Java 1.0 language specification. Sun Microsystems released the first public implementation as Java 1.0 in 1996.
These downloads can be used for development, personal use, or within Oracle Cloud. The Oracle JDK 8 license changed in April 2019TheOracle Technology Network License Agreementfor Oracle Java SE is substantially different from prior Oracle JDK 8 licenses. Use for otherpurposes, including production or commercial use, requires a Java SE Universal Subscription or another Oracle license. Subsequent JDK 21 updates will be licensed under the Java SE OTN License (OTN) and production use beyond the limited free grants of the OTN license will require a fee. Subsequent JDK 25 updates will be licensed under the Java SE OTN License (OTN) and production use beyond the limited free grants of the OTN license will require a fee.
It is guaranteed to be triggered if there is insufficient free memory on the heap to allocate a new object; this can cause a program to stall momentarily. In some languages, memory for the creation of objects is implicitly allocated on the stack or explicitly allocated and deallocated from the heap. Once no references to an object remain, the unreachable memory becomes eligible to be freed automatically by the garbage collector. Java uses an automatic garbage collector to manage memory in the object lifecycle.
Please save your data and refresh page to update. Java File Handling enables programs to create, read, write, and manipulate files stored on the system. Java Multithreading allows concurrent execution of two or more threads, enabling efficient CPU utilization and faster program performance. Lambdas provide concise syntax for anonymous functions, while Streams allow efficient filtering, mapping, and reduction of data. Java Streams and Lambda Expressions simplify data processing by enabling functional-style operations on collections.

Special classes

Builders don't just know how to code, they create solutions that matter. Then, execute your program with Now, open your command prompt, navigate to the location of that program, and compile with Then save this file as HelloWorld.java (select "All Files" in "Save as type").
Java applications are typically compiled to bytecode that can run on any Java virtual machine (JVM) regardless of the underlying computer architecture. It includes interfaces like List, Set, and Map, along with classes like ArrayList, HashSet, and HashMap. It involves stack and heap memory, with the JVM managing allocation and garbage collection automatically. Java Exception Handling is a mechanism to handle runtime errors, ensuring the program runs smoothly without crashing. Java methods are reusable blocks of code that perform specific tasks and help organize your program. Java is an object oriented language and some concepts may be new.

• J2EE included technologies and APIs for enterprise applications typically run in server environments, while J2ME featured APIs optimized for mobile applications.
• End-users commonly use a Java Runtime Environment (JRE) installed on their device for standalone Java applications or a web browser for Java applets.
• In January 2016, Oracle announced that Java run-time environments based on JDK 9 will discontinue the browser plugin.
• The Android SDK is an alternative software platform, used primarily for developing Android applications with its own GUI system.
• Each package contains a set of related interfaces, classes, subpackages and exceptions.

JavaFX is a software platform for creating and delivering desktop applications, as well as rich web applications that can run across a wide variety of devices. Unlike C++, Java does not support operator overloading or multiple inheritance for classes, though multiple inheritance is supported for interfaces. Unlike C++, which combines the syntax for structured, generic, and object-oriented programming, Java was built almost exclusively as an object-oriented language.
Companies or individuals participating in this process can influence the design and development of the APIs. It is controlled by Oracle in cooperation with others through the Java Community Process program. If Java prevented all runtime type errors (ClassCastExceptions) from occurring, it would be type safe. Either the container operates on all subtypes of a class or interface, usually Object, or a different container class has to be created for each contained class. In 2004, generics were added to the Java language, as part of J2SE 5.0. JavaFX has support for desktop computers and web browsers on Microsoft Windows, Linux, and macOS.

Java Arrays

Although Android, built on the Linux kernel, is written largely in C, the Android SDK uses the Java language as the basis for Android applications but does not use any of its standard GUI, SE, ME or other established Java standards. The Android SDK is an alternative software platform, used primarily for developing Android applications with its own GUI system. This resulted in a legal dispute with Microsoft after Sun claimed that the Microsoft implementation did not support Java remote method invocation (RMI) or Java Native Interface (JNI) and had added platform-specific features of their own. The Java Class Library is the standard library, developed to support application development in Java.
JDK 8 software is licensed under theOracle Technology NetworkLicense Agreement for Oracle Java SE. Please review the terms carefully before downloading and using this product.FAQs are availablehere.Commercial license and support are available for a low cost withJava SE Universal Subscription. This license permits certainuses, such as personal use and development use, at no cost — but other uses authorized under prior Oracle JDKlicenses may no longer be available. JDK 11 software is licensed under theOracle Technology NetworkLicense Agreement for Oracle Java SE. Commercial license and support are available for a low cost withJava SE Universal Subscription.
Each package contains a set of luckystar casino related interfaces, classes, subpackages and exceptions. The classes in the Java APIs are organized into separate groups called packages. Sun has defined and supports four editions of Java targeting different application environments and segmented many of its APIs so that they belong to one of the platforms.

• It is controlled by Oracle in cooperation with others through the Java Community Process program.
• In the latter case, the responsibility of managing memory resides with the programmer.
• As of September 2025update, Java 8, 11, 17, 21, and 25 are supported as long-term support (LTS) versions.
• As of Java SE 7, OpenJDK is the official Java reference implementation.
• Just-in-time (JIT) compilers that compile byte-codes to machine code during runtime were introduced from an early stage.
• Sun has defined and supports four editions of Java targeting different application environments and segmented many of its APIs so that they belong to one of the platforms.

Java Queue

Java Collections provide a framework for storing and manipulating groups of objects efficiently. They enable abstraction and support multiple inheritance in Java through a clean, structured approach. Java Regex (Regular Expressions) allows pattern matching and text manipulation using the java.util.regex package. They provide an efficient way to manage and access collections of data using index-based positions. Java arrays are containers that store multiple values of the same data type in a single variable. Visit dev.java for the latest Java developer newsand resources.
Most of the time, this means generating HTML pages in response to HTTP requests, although there are a number of other standard servlet classes available, for example for WebSocket communication. Something similar to a memory leak may still occur if a programmer's code holds a reference to an object that is no longer needed, typically when objects that are no longer needed are stored in containers that are still in use. The programmer determines when objects are created, and the Java runtime is responsible for recovering the memory once objects are no longer in use. Java itself is platform-independent and is adapted to the particular platform it is to run on by a Java virtual machine (JVM), which translates the Java bytecode into the platform's machine language. One design goal of Java is portability, which means that programs written for the Java platform must run similarly on any combination of hardware and operating system with adequate run time support. The original and reference implementation Java compilers, virtual machines, and class libraries were released by Sun under proprietary licenses.

Take breaks when needed, and goover the examples as many times as needed. You can edit Java code and view the result in your browser. The Java language is a key pillar in Android, an open source mobile operating system. Platform-independent Java is essential to Java EE, and an even more rigorous validation is required to certify an implementation.
Java 8, 11, 17, 21, and 25 are long-term support versions still under maintenance. As of May 2007, in compliance with the specifications of the Java Community Process, Sun had relicensed most of its Java technologies under the GPL-2.0-only license. It was released in May 1995 as a core component of Sun's Java platform.

On May 8, 2007, Sun finished the process, making all of its JVM's core code available under free software/open-source distribution terms, aside from a small portion of code to which Sun did not hold the copyright. It promised write once, run anywhere (WORA) functionality, providing no-cost run-times on popular platforms. However, the official reference implementation is the OpenJDK JVM, which is open-source software used by most developers and is the default JVM for almost all Linux distributions. Java was the third most popular programming language in 2022update according to GitHub. Java gained popularity shortly after its release, and has been a popular programming language since then. For developers that want to try out early-access builds, or builds by projects like Loom, Valhalla, and Panama, then you can find builds of theseat jdk.java.net.