Reserved Words in Java

Here's the full list of words you cannot use in Java

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Reserved words are words that cannot be used as object or variable names in a Java program because they're already used by the syntax of the Java programming language.

If you ttempt to use any of the words below as identifiers in your Java programs, you'll get an error like the one below.

List of Reserved Java Keywords

abstract assert boolean break byte case
catch char class const continue default
double do else enum extends false
final finally float for goto if
implements import instanceof int interface long
native new null package private protected
public return short static strictfp super
switch synchronized this throw throws transient
true try void volatile while

*The strictfp keyword was added to this list in Java Standard Edition version 1.2, assert in version 1.4, and enum in version 5.0.

Even though goto and const are no longer used in the Java programming language, they still cannot be used as keywords.

What Happens If You Use a Reserved Word?

Let's say you try to create a new class and name it using a reserved word, like this:

 // you can't use finally as it's a reserved word!
class finally {

   public static void main(String[] args) {

      //class code..


Instead of compiling, the Java program will instead give the following error:

mla apa chicago
Your Citation
Leahy, Paul. "Reserved Words in Java." ThoughtCo, Aug. 26, 2020, Leahy, Paul. (2020, August 26). Reserved Words in Java. Retrieved from Leahy, Paul. "Reserved Words in Java." ThoughtCo. (accessed June 7, 2023).