Summary of all Java keywords with code examples

Details: Written by Nam Ha Minh; Last Updated on 09 March 2024 | Print Email

This article gives you an overview of all keywords in the Java programming language with explanation and code examples (updated to Java 14). Understand the meaning of each Java keyword will help you write better and more precise code, e.g. know when to use public or private for a variable or class.

Beginners in Java programming will find the list below helpful in terms of getting started with Java from the ground up. And senior Java programmers will also find this article helpful in terms of reviewing all Java keywords updated to the most recent release of Java.

You know, the Java programming language has over 50 reserved keywords which have special meaning for the compiler and cannot be used as variable names. Following is a list of Java keywords in alphabetical order. You can click on an individual keyword to see its description and usage example.

List of all keywords in Java (updated to Java 14):

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

Some noteworthy points regarding Java keywords:

- const and goto are resevered words but not used.
- true, false and null are literals, not keywords.
- Since Java 8, the default keyword is also used to declare default methods in interfaces.
- Since Java 10, the word var is used to declare local variables (local variables type inference). For backward compatibility, you can still use var as variable names. So var is a reserved word, not keyword.
- Java 14 adds two new keywords record and yield (but in preview mode)
- all keywords are in lower-case.

And based on categories, the keywords in Java can be grouped as follows:

Java keywords for access modifiers: private, protected, public

Java keywords for class, method, variable modifiers:

abstract, class, default, extends, final,

implements, interface, native, new,

static, strictfp, synchronized, transient,

var, record, volatile

Java keywords for Flow control:

break, case, continue, default, do, else,

for, if, instanceof, return, switch, while,

yield

Java keywords for package control: import, package

Java keywords for primitive types: boolean, byte, char,

double, float, int, long, short

Java keyword for error handling: assert, catch, finally,

throw, throws, try

Java keyword for enumeration: enum

Other Java keywords: super, this, void

Unused (reserved) Java keywords: const, goto

About the Author:

Nam Ha Minh is certified Java programmer (SCJP and SCWCD). He began programming with Java back in the days of Java 1.4 and has been passionate about it ever since. You can connect with him on Facebook and watch his Java videos on YouTube.