This posts is introduce Types of variables in Java. Have 03 types of variables:
- Local Variables
- Instance Variables
- Static Variables
1. Instance Variables
Define: Declared Inside class but not inside method
- Examples:
class Test { int data = 15; // Instance variable float pi = 3.14f; // Instance variable
}
Properties of Instance Variable:
- Instance variable always get a default value: Ex: int data
- Cannot be reinitialized directly within class Examples:
class Test { int data = 15; data = 20; // Error
}
But is that TRUE if reinit in method
class Test { int data = 15; void someMethod(){ data = 20; //allowed }
}
2. Static Variables:
detail...to be updated
3. Local Variables
Define: Declared Inside method or method parameters
- Examples:
int areaCircle(int radius) { int total = radius * radius; return total;
}
Properties of Local Variable:
- Not accessible outside method
- Do not get default value
4. Summary
- Examples:
public class Practice { static int staticVariables = 20; int instanceVariables = 30; void someMethod(){ int localVariables = 10; } public static void main(String[] args) { Practice obj1 = new Practice(); System.out.println(obj1.instanceVariables); System.out.println(Practice.staticVariables); }
}