What is the Difference Between JDK and JRE? with Proper Definition and Brief Explanation

The main difference between them is that the JDK provides the environment for developing and running Java programs while the JRE only provides the environment for running Java programs.

Java is a high-level programming language that was originally developed by Sun Microsystems. It is used to create various applications such as business applications and mobile applications. Java provides multiple advantages. It supports object-oriented programming and helps develop secure and robust applications. JDK and JRE are related to Java application development. JDK is the software development environment used to develop Java applications. It consists of the JRE and the other development tools. On the other hand, JRE provides a runtime environment and consists of JVM, class libraries, and other files.

Key Areas Covered

1. What is JVM?
     – Definition, Functionality
2. What is JRE?
     – Definition, Functionality
3. What is JDK?
      – Definition, Functionality
4. Difference Between JDK and JRE?
      – Key Differences Comparison

Key terms

Java, JDK, JRE, JVM

What is JVM?

A Java program is a set of instructions written using the Java programming language that directs the computer to perform a specific task. It is also known as the source code. When the programmer writes the Java program and compiles it, the Java compiler converts the Java program into intermediate code called bytecode. The JVM stands for Java Virtual Machine. It is an abstract machine that converts byte code to machine code.

The source code is not understandable by the CPU. It is only understandable by the programmer. Thus, the source code is converted into a machine readable and understandable machine code. Therefore, the CPU will execute the task according to the given instructions of the program.

If the Java program is converted directly to machine code, it will not be possible to run that code on other platforms. When Java code is converted to bytecode, it is not written for the physical machine. It is written for JVM. Therefore, the bytecode is platform independent. This makes the Java language platform independent.

what is JRE?

JRE stands for Java Runtime Environment . JRE is the combination of JVM, Java class libraries, and other files required to run Java applications. It is a superset of JVM. When the programmer installs the JRE, it is only possible to run the Java program. It is not possible to develop the program. Therefore, the JRE is only used to run Java programs.

What is JDK?

JDK stands for Java Development Kit . Helps develop Java-based applications. When the programmer installs the JDK, there is no need to download the JRE separately because the JRE is already installed with the JDK. JDK is an implementation of Java platforms such as Standard Edition, Enterprise Edition, and Micro Edition released by Oracle Corporation.

JDK consists of the JRE and other development tools. These development tools include a compiler (javac), an archiver (jar), a documentation generator (javadoc), etc. These tools help to complete the Java application development.

Relationship

• JDK is the combination of JRE and other development tools.

Key Differences

Definition

JDK is a software development environment used to develop Java applications on Java platforms such as Standard Edition, Enterprise Edition, and Micro Edition. JRE is a part of JDK that provides the minimum requirement to run Java applications. This is the basic difference between them.

Use

While the JDK allows you to develop and run Java programs, the JRE is only a part of it that allows you to run Java programs.

Consists in

JDK consists of JRE and other development tools. JRE consists of JVM, class libraries, and other supporting files.

Conclusion

The difference between them is that JDK provides the environment for developing and running Java programs, while JRE only provides the environment for running Java programs. In short, JDK is the combination of JDE and development tools while JRE is the combination of JVM and library files.

Reference

1. “Java JDK, JRE, and JVM.” Java If, If … else Statement (with examples) , Available here.

Courtesy image:

1. “JavaSE Software Architecture” By Sergelucas – Own work (CC BY-SA 3.0) via Commons Wikimedia

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