java is a high-level, class-based, object-oriented programming language that is designed to have as few implementation dependencies as possible. It is a general-purpose programming language intended to let programmers write once, run anywhere (WORA), meaning that compiled Java code can run on all platforms that support Java without the need to recompile. Java applications are typically compiled to bytecode that can run on any Java virtual machine (JVM) regardless of the underlying computer architecture. The syntax of Java is similar to C and C++, but has fewer low-level facilities than either of them. The Java runtime provides dynamic capabilities (such as reflection and runtime code modification) that are typically not available in traditional compiled languages. As of 2019, Java was one of the most popular programming languages in use according to GitHub, particularly for clientserver web applications, with a reported 9 million developers.Java was originally developed by James Gosling at Sun Microsystems and released in May 1995 as a core component of Sun Microsystems’ Java platform. The original and reference implementation Java compilers, virtual machines, and class libraries were originally released by Sun under proprietary licenses. 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. Oracle offers its own HotSpot Java Virtual Machine, however the official reference implementation is the OpenJDK JVM which is free open-source software and used by most developers and is the default JVM for almost all Linux distributions.
As of March 2022, Java 18 is the latest version, while Java 17, 11 and 8 are the current long-term support (LTS) versions.
create Your First Java Program on Ubuntu Linux
1 – Open terminal on your system after installing Java on your system.
2 – Create a directory to hold your Java programs.
3 – Type:
4 – Navigate to your Java_Applications directory.
5 – Use a text editor such as nano or gedit to create a java file.
6 – Enter the following code below.
7 – Save the file as HelloWorld.java
8 – Compile the HelloWorld.java file into a Java class file by issuing the following command below.
9 – Run or execute your Java class file by issuing the following command.