Here's a list of Java's keywords. These words are reserved--you cannot use any of these words as names in your Java programs. true, false, and null are not keywords but they are reserved words, so you cannot use them as names in your programs either.

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

The words with asterisks are reserved and not currently used. Note that all of the keywords are in lowercase, thus for is a keyword but FOR is not.