Reserved Words in Java

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

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Updated on January 27, 2019

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:

 expected