When we want to store any information, we store it in an address of the computer. Instead of remembering the complex address where we have stored our information, we name that address.The naming of an address is known as variable. Variable is the name of memory location.
To declare the variable in Java, we can use following syntax
Here, datatype refers to type of variable which can any like: int, float etc. and variableName can be any like: empId, amount, price etc.
Java Programming language defines mainly three kind of variables.
Static Variables (Class Variables)
Instance variables in Java
Instance variables are variables that are declare inside a class but outside any method,constructor or block. Instance variable are also variable of object commonly known as field or property. They are referred as object variable. Each object has its own copy of each variable and thus, it doesn't effect the instance variable if one object changes the value of the variable.
Static variables in Java
Static are class variables declared with static keyword. Static variables are initialized only once. Static variables are also used in declaring constant along with final keyword.
Local variables in Java
Local variables are declared in method, constructor or block. Local variables are initialized when method, constructor or block start and will be destroyed once its end. Local variable reside in stack. Access modifiers are not used for local variable.