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Java Local Development Environments How it Works T.M.A. - Too Many Acronyms

java command

To run a java program we type "java MainClassName" in terminal window. What is happening behind the scenes when we type this command. Are running our program with JRE when we type this command?

There is a java in the JDK graphics craig showed and it is out of JRE is that the same java we used to run our code. if yes why it is out of JRE while JRE is important to run java code?

Please explain!

2 Answers

Kristian Gausel
Kristian Gausel
14,661 Points

So typing "java ClassName" is how you run any java program, which is ran with the JRE (Java Runtime Environment). You need the JDK (Java Development Kit) to compile the java files to java bytecode (which is done with javac, which is the java compiler)

The "There is a java" part I do not really understand. what do you mean by "a java"?

Kristian Gausel

http://docs.oracle.com/javase/8/docs/

there is a java in the graphical display of the java platform which is outside the JRE.