Reserved Words

Java reserved words cannot be used in any capacity other than their intended purpose. You cannot use these words for variables, methods, classes, or anything else. Many of these aren't used in this course, and won't be assessed on the AP exam.

Reserved Word	Description
abstract	An abstract class or method.
assert	An assertion that a condition is met, often used during debugging.
boolean	A primitive data type that stores true and false values.
break	Breaks out of a switch statement or loop.
byte	A primitive data type that stores 8-bit integers.
case	A label in a switch statement.
catch	The clause of a try block designed to handle an exception.
char	A primitive data type that stores Unicode characters.
class	Defines a class type.
const	Unused but reserved nonetheless.
continue	Skips the remainder of a loop body.
default	The default clause of a switch statement, or a default method in an interface.
do	The opening component of a do...while loop.
double	A primitive data type that stores double-precision floating-point numbers.
else	The alternative clause of an if statement.
enum	An enumerated type.
extends	Indicates that a class is the subclass of another.
final	A constant, or a class or method that cannot be extended or overridden.
finally	The clause of a try block that is always executed.
float	A primitive data type that stores single-precision floating-point numbers.
for	A loop type.
goto	Unused but reserved nonetheless.
if	A conditional control statement.
implements	Defines the interface(s) that a class implements.
import	Imports a package.
instanceof	Tests if an object is an instance of a particular class.
int	A primitive data type that stores 32-bit integers.
interface	An abstract type with methods that a class can implement.
long	A primitive data type that stores 64-bit integers.
native	A method implemented by the host system.
new	Allocated a new object or array.
null	A null reference (technically a literal, rather than a keyword).
package	A package of classes.
private	A feature that is accessible only by methods of the same class.
protected	A feature that is accessible only by methods of the same class, its children, and classes in the same package.
public	A feature that is accessible by methods of all classes.
return	Returns a value from a method.
short	A primitive data type that stores 16-bit integers.
static	A feature that is unique to a class or interface, but not to an instance of the class.
strictfp	Use strict rules for floating-point computations.
super	Invokes a constructor or method of the parent class.
switch	A multiple selection statement.
synchronized	A method or block of code that is atomic to a thread.
this	The implicit argument of a method, or invocation of a constructor of the same class.
throw	Throws an exception.
throws	The exceptions that a method can throw.
transient	Marks instance variables that should not be persisted (or serialized).
try	A block of code with exception handling.
void	Denotes a method that returns no value.
volatile	Ensures that a variable is coherently accessed by multiple threads.
while	A loop type.