What is Java?

Many people often wonder, what is Java and what is Java used for? After all that coffee cup symbol which denotes that Java programming was used seemingly appears all over the internet on a large number of websites. In simple words, it’s a popular programming language which enables software programs to be written which can then run on any hardware and any operating system without requiring any changes to the source code. Java uses the concept of virtual machines to abstract hardware details and allows programs to be built that run seamlessly on all platforms.

1.0 What is Java and What is Java Used For?

Many people want to learn Java but the simple question ‘What is Java and what is Java used for’ scares them away. Contrary to some people’s mis-belief, Java is a developer friendly language and pretty easy to learn as compared to other programming languages particularly those which do not follow the Object Oriented Programming paradigm. So, there’s absolutely no reason to be scared if someone asks you - what is Java?

2.0 What is Java Founding Principle?

Every programming language is designed with a definite goal and many developers are often faced with the question – what is Java founding principle? Sun Microsystems’s founding principle for Java is ‘Write Once, Run everywhere’. As a developer, you just write the source code without worrying about the operating system and the hardware architecture of the computer where the program will eventually run. Although there have been other languages which have tried to provide such seamless interoperability across operating systems and system architectures, no language has been as successful as Java.

As such Java works well within the normal process of software development and also the software testing life cycle

2.1 Tip

Java does have the ability to take advantage of specific operating system features through an interface called JNI (Java Native Interface).

3.0 What is Java Runtime?

When people ask, “What is Java Used For?” they are usually asking about the Java Runtime which is the environment required to execute Java programs. This comprises of the Java Virtual Machine (JVM), Java libraries and supporting applications/ tools. The Runtime also known as JRE enables running applications seamlessly on all platforms. So if someone asks you ‘what is Java Runtime Environment’, you know that it’s the set of tools and software that runs/ executes your Java program.

3.1 Tip

Make sure that you have the JDK and Java Runtime installed on your computer before you start writing programs in Java

4.0 What is Java Bytecode?

Java Bytecode is the low level source code that is executed by JVM when you run your Java program. When you compile your program, the Java compiler produces an output in Bytecode form.

5.0 What is Java Compiler?

A Java Compiler is a tool which compilers your source code and generates Bytecode output which can then be executed by the Java Runtime. While Java compilers are common, not everyone can answer the question – what is Java decompiler? In simple words, it’s a tool which can convert the Java Bytecode back into original source code.

5.1 Tip

Many professional developers often use a technique called obfuscation which ensures that it’s not possible to use de-compilers to generate the source code from the class files.

6.0 What is a Java Applet?

A Java program which executes within a web browser is called a Java applet. These will often be the subject of a software requirements specification.

7.0 What is Java Enabled Phone?

The words ‘Java Enabled’ or ‘Java Powered’ can often be found written on the back panels of many mobile phones. If you ever wondered what it implies, it means that the phone can run Java applications be it games, instant messengers or any other utility/ tool.

8.0 What is Java Latest Release?

As a Java developer/ enthusiast, it is critical that you know what is the Java latest version and what is Java version history. This is important because significant updates are made to each Java release and some APIs get deprecated with each new release.

The website of Sun Microsystems is a good place to check ‘what is Java latest stable release’ that you should use for developing your Java programs.

The popularity of Java has been steadily on a rise ever since it was launched and it’s undoubtedly the most widely used programming language all over the world.

What is Java? - Tip

Remember the following, "Write once, Run everywhere, Have fun!"

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