Computer programming is a continuous and fastest changing arena. One of the purposes of programming is to find a solution to a problem in a typical way. Programmers need to keep updating their knowledge and skills to address new challenges. Besides having a very good programming knowledge, it is very important that they also understand the internal structure of the environment in which they are the writing the code.
In this blog we are going to discuss 3 important components of Java Programming language. Knowing these 3 components is a must for any Java developer. We also suggest you to read our blog on Learn 7 Basics of Java Programming to Start Coding Today, which discusses the basic concepts of Java Programming.
In this blog we will cover the following topics:
- What is Java?
- Features of Java
- 3 Components of Java Programming Language
- Differences between JRE VS JVM VS JDK.
Now at first let us discuss What is Java
What is Java?
Java is a general-purpose, object-oriented, widely used programming language developed by Sun Microsystems in the year 1991. It is regarded as one of the fast, secure and reliable programming language that is preferred by most of the organizations to build their projects including web applications, gaming software, and android applications etc.
Did You Know? One Billion downloads: Java gets downloaded one billion times a year!
Java is one of the easy programming languages to learn. Some of the reasons why it has an upper hand over the other programming are:
- It is platform independent
- It is a class-based object-oriented language that reduces complexity of coding.
These factors make it an easy program language to learn. Anyone can learn this programming language easily even if they don’t any prior knowledge of computer language but have a strong desire to learn it.
Features Of Java Programming
- Easy to learn: As discussed in the above section, Java is one of the easiest programming languages to learn. To learn Java you need not to have any prior knowledge of basic programming language but instead need a strong desire to learn.
- Support Object-Oriented: The one of the advantage of using Java is that it supports Object-Oriented concept. This makes it easy for developers to build their projects easily using Java.
- Platform independent: One of the biggest strengths of Java programming language is that it is platform independent. This feature makes it a platform independent programming language.
Being a platform independent means a program compiled on one machine can be easily executed on any other machine without making any changes.
- Java is multithreaded: Multithreaded means handling different tasks simultaneously. Java programming language supports multithreaded programs, meaning that no need to wait for one task to finish for another to start.
- High performance: With the use of Just-In-Time compilers, Java enables high performance.
- Distributed: Java programming language is designed for the distributed environment of the Internet.
3 Components Of Java Programming Language
A Java Programmer writes a program in a human-readable language, called Source Code. The CPU or Central Processing Unit or Chips do not understand the source code written in any programming language. These chips or computers understand only one thing: Machine Code or Machine Language. These machine codes run at CPU level; hence, it would be different machine codes for different models of CPU.
We need not to worry about the machine code, as programming for us is all about the source code. To help the machine to understand the source code, it needs to be converted into a machine level language which is an executable code.
All these functionalities happen inside following 3 components of Java Programming Language:
- Java Virtual Machine (JVM)
- Java Runtime Environment (JRE)
- Java Development Kit (JDK).
Let us discuss these 3 components of Java programming language in detail
What is JVM?
JVM stands for Java Virtual Machine and it is the center of Java programming language and Java platform. Java Virtual Machine (JVM) is an engine that provides a runtime environment to drive the Java Code or applications. It performs the operation of converting Java bytecode into machine language. JVM is a part of JRE. It cannot be separately installed, to install JVM you need to install JRE.
Usage of JVM:
- JVM is platform independent and this factor helps the developer to create Java Programs on one machine and execute them on another machine.
- JVM provides numerous libraries, tools and frameworks
- JVM comes up with JIT (Just-In-Time) compiler that converts Java source code into low-level machine language. It is the reason that JVM is faster as a regular application.
Did You Know? There are 3 billion phones and counting number of mobile phones that are running help of the platform built using Java
What is JRE?
JRE stands for Java Runtime Environment. It is a runtime environment that is required to execute Java programs and applications. JRE contains JVM and binaries and other classes to successfully execute Java programs. It does not have tool for Java development like a debugger, compiler etc.
If anyone wants to run Java programs in their machines then it is must that you have JRE installed on your machine. It’s a platform dependent, it means you need to download and install JRE that are compatible with your Operating System and architecture.
What is JDK?
JDK is the core component of Java environment. It contains JRE (Java Runtime Environment) along with Java compiler, Java debugger, and other classes. JDK is used for Java development as it provides the entire executable and binaries as well as tools required to compile, debug a Java program. JDK is a superset of JRE as it contains JRE and development tools.
Now that we have discussed the 3 main components of Java language along with their functionalities and how they are related to each other, we are ready to download Java Development Kit here and start writing Java programs.
With so many different Java terms around it is always to have a Java Glossary handy, which you can refer here.
Programmers write programs to communicate with the computer. However, each of the many programming languages comes with its own unique features and provides different kinds of applications. As each programming language is different, a particular one might be best suited for a specific purpose or for specific industries.
In continuation of our discussion, now, let us look at some of the applications Java provides.
Some of the applications of Java programs:
- Mobile applications: One of the prominent applications of Java is developing Mobile applications. Java platform, Micro Edition is a cross-platform framework which is used to develop applications across all the Java supporting devices. This framework is used to develop the features of smartphones. Applications for the popular mobile operating system android are developed using Java, using the Android Software Development Kit (SDK) or other environments.
- Desktop GUI applications: The other important application of Java is that it provides GUI development through various means like Abstract Windowing Toolkit(AWT), JavaFX and Swing.
- Web applications: Java provides many web applications through Servlets, Struts and JSP’s. With the flexibility that Java provides, one can easily develop web applications as per the customer requirements.
- Enterprise applications: Java programming language would be the first choice of developers when it comes to developing enterprise applications because of its features that match the requirements. The application which is distributed in nature such as banking application is the example of enterprise applications. Java EE platform is designed in such a way that reduces the complexity of enterprise application development.
- Scientific applications: Java is the preferred programming language for developing scientific applications. Most of the scientific software are written in Java.
Difference Between JVM VS JRE VS JDK
The major differences between JVM VS JRE VS JDK are as follows:
|The acronym of JVM is Java Virtual Machine||The acronym of JRE is Java Runtime Environment||The acronym of JDK is Java Development Kit|
|JVM is platform independent||JRE is platform independent||JDK is platform dependent|
|JVM is a subset of JRE||JRE is subset of JDK||JDK is a superset of JDK|
|JVM is a Java Platform Component that executes source code||JRE is a part of Java that creates the JVM||The JDK enables the developers to create Java programs which can be executed and run by JRE and JVM.|
|JVM bundled in both software JDK and JRE||JRE only contain environment to execute source code||JDK comes with the installer|
Conclusion: This has been a guide to discuss about What is Java, Features of Java Programming Language, 3 Components of Java Programming such as JVM, JRE and JDK and also about the Differences between JVM VS JDK VS JRE.
Here we have discussed about Java Development Kit which contains Java Runtime Environment (JRE) and Java compiler. JRE in turn, contains JVM that is responsible for converting byte code generated by Java compiler into machine-specific code.
If you think some more information needed to be added here or have any questions related to any of the topic discussed above, then please share your feedback in the comment section below.
In supplement to all the information discussed above, now we recommend you to go through these online courses that contain a bundle of Java courses that can be of very useful to you.
Thanks for reading!