RESERVED WORDS IN JAVA

 

 

Keyword                Contextual Description

 

abstract                 Used in a class definition to specify that a class is not to be instantiated, but rather inherited by other classes

boolean                  Refers to an expression or variable that can have only a true or false value

break                     Terminates processing of a switch statement or loop

byte                         A sequence of eight bits

case                        Used in a switch statement to specify a match for the statement's expression

catch                      Used to specify the actions to be taken when an exception occurs (see throw, try)

char                        Declares objects whose values are characters

class                       Construct new types to describe data and operations

continue                Used in a loop statement to transfer control to the beginning of the loop

default                    Used in a switch statement to handle expression values not specified using case

do                            Marks the beginning of a do-while statement

double                    Declares objects whose values are double precision real numbers

else                         Used as the alternative action of an if statement

extends                  Used to specify that a subclass inherits the methods of a superclass

final                        An entity that is defined once and cannot be changed or derived from later

finally                    Executes a block of statements regardless of whether a Java Exception, or run time error, occurred in a block defined previously by the "try" keyword

float                        Declares a primitive data type whose values are single precision real numbers

for                           Marks the beginning of a for statement

if                             Marks the beginning of an if statement

implements           Optionally included in the class declaration to specify any interfaces that are implemented by the current class

import                    Used at the beginning of a source file that can specify classes or entire packages to be referred to later without including their package names in the reference

instanceof             tests whether the run-time type of its first argument is assignment compatible with its second argument

int                           Declares objects whose values are integer numbers

interface                used to define a collection of method definitions and constant values

long                        Used to declare a primitive data type with values that range from

new                         Allocates memory dynamically at run-time

package                 A group of types

private                    Declares class members that are inaccessible from outside of the class

protected               Declares class members that are private, except to derived classes

public                     Declares class members that can be accessed outside of the class

return                    Terminates a function, usually returning the value of some expression

short                      Used to declare 16-bit integer numbers

static                      Declares objects whose lifetime is the duration of the program

super                      Used to access members of a class inherited by the class in which it appears

switch                    Marks the beginning of a switch statement

synchronized        When applied to a method or code block, guarantees that at most one thread at a time executes that code

this                         Used with a class member to unambiguously access other members of the class

throw                      Used to generate an exception (see catch, try)

throws                    Used in method declarations that specify which exceptions are not handled within the method but rather passed to the next higher level of the program

try                           Used to mark the beginning of a block containing exception handlers (see catch)

void                         Used to indicate the absence of any type (for a function or parameter list)

while                      Marks the beginning of a while statement, as well as the end of a do-while statement