JAVA Keywords
=============
Keywords in Java are words or expressions used to declare an expression, method or return value.
About the number of those keywords some say that there are 48, some 50, some others 52.
Here we have 51;There are:
byte, boolean, break, case, char, continue, float, for, if, else, import, int,interface, long, new, package, private, protected, public, return, short, this, void, abstract, assert, catch, class, const, default, do, enum, extends, final, finally, goto, instanceof, native, static, strictfp, super,switch, synchronized, throw, throws, transient, try, volatile, while, false, true, null.
Here we will just give and try to explain some of them.
We will beggin by the most common used:
- byte: Is used to return a 8-bit value;
- boolean : Used to return a boolean value(true or false);
- break: Used to stop immediately the execution of a statement;
- case: Used to declare individual cases of statements;
- char: Is used to return a 16-bit unicode value;
- continue: used to resume a current loop;
- extends : Used in interface;
- final: Used for expression which cannot be changed, a final class
cannot be subclassed, a final method cannot be overriden, a final
variable can occur at most once.
- float : Is used to return a 32-bit value;
- for: Used to create a loop using some conditions;
- if -else: Used when we need to verify if the statement is true or
false.it will run if it is true, block the statement if it is false;
- implements : Used in interface;
- import: As the meaning of the name, used to import some classes,
function without using the whole package;
- int: Is used to return a value of type int which means a value
which has 32 bits;
- interface: Used to declare a special class that will be used by
implementation or extends. That class only contain abstracts methods
- long: Is used to return 64-bit value;
- new: Used to create a obect, an array
- package: "package" is a group of types (classes, enum, interface);
- private: The "private" keyword is also used in declaration of
function, classes and means that the element can only be used by
the class which contain it. A private function from an inherit
father class can't be used in a subclass;
- protected: The use of "protected" keyword is the same as the one
of "private" on the difference that it can only be used by the
variable or function in the same package, class or function;
- public: The "public" keyword is used in declaration of functions,
classes and means that the class (function) can be used by every
other class in the same package;
- return: Is used to finish a execution of a method and will be
followed by a particle which needs to be to be called at the end of
the execution;
- short: Is used to return 16-bit value;
- static: a static function can be run directly by the class without
creating an object. static obecjts can alse be used by other
classes in this format(classname.objectname);
- super: will call a method from an inherit parent class;
- this: Used to give a relationship between a function and a variable
- void: Is used to declare a function tahat doesn't return any value;
- false: Used in boolean to mean that a statement is false;
- true: Used in boolean to mean that a statement is true;
- null: Which means without value,
- while: Used to create a loop which use the boolean expression.
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