Variable Name & Type

Naming in AJCG

• Start with letter, end with letter or digit
• Only digit ,letter and '_' can be used
• Name should be meaningful
• Use Camel-Case

Type

How to define a variable

• We must use:

1.F to tell it's a float type value(not double)
2.L to tell it's a long type value
3.If we need to initial a character variable, we can use '\0'

class Demo2 {
    public static void main(String[] args) {
        /*
        Define Variable
        */
        
        /*Integer*/
        byte byteNumber = 10;
        short shortNumber = 20;
        int intNumber = 30;
        long longNumber = 40L; //L means 40 is a long type
        
        System.out.println("Value of byte type:" + byteNumber);
        System.out.println("Value of short type:" + shortNumber);
        System.out.println("Value of int type:" + intNumber);
        System.out.println("Value of long type:" + longNumber);
        
        /*Float*/
        float floatNumber = 3.14F;  //We must use F to tell it's a float type value
        double doubleNumber = 3.14;
        System.out.println("Value of float type:" + floatNumber);
        System.out.println("Value of double type:" + doubleNumber);
        
        /*Boolean*/
        boolean ret = false;
        System.out.println("Value of boolean type:" + ret);
        
        /*Character*/
        char ch = 'T';
        System.out.println("Value of char type:" + ch);
    }
}