Non - Primitive Datatypes

Wrapper Class 

👉 Program 1

class wrap
{
public static void main(String wrp[])
{
//primitive declaration
int p = 100;
System.out.println("primitive datatype = "  +p);

//non-primitive declaration
Integer h = new Integer(100);
System.out.println("non-primitive datatype = "  +h
);

Double d = new Double(2.1756);
System.out.println("non-primitive datatype = "  +d);

Character c = new Character('K');
System.out.println("non-primitive datatype = "  +c);

}


}

Output 

Variables and Datatypes

■Write a program to print the values of a variables declared 

    using primitive datatypes:

üboolean

übyte

üshort

üint

ülong

üchar

üfloat

üdouble

Sol.   

 class datatype

{

public static void main(String data[])

{

//primitive datatypes

boolean a = false;

System.out.println("boolean is"+a+"by default");

//here + means concatenation

//byte datatype

byte b = 2;

System.out.println("byte is" +b);

//short datatype

short s = 20;

System.out.println("short is" +s);

//int datatype

int i = 200;

System.out.println("integer is" +i);

//long datatype

long l = 2000;

System.out.println("long is" +l);

//char datatype

char ch = 'A';

//char always declared in single quotes

System.out.println("char is" +ch);

//float datatype

float f = 2000000000f;

//0f means representing float numbers

System.out.println("float is" +f);

//double datatype

double d= 2000000000d;

//0d means representing double numbers

System.out.println("double is" +d);

}

}

Output:

JAVA PROGRAMS

👉 Program below shows the basic difference between Post/Pre increment and decrement :

class unoperator

{

public static void main(String args[])

{

int a = 20;

System.out.println(a++);

System.out.println(a--);

System.out.println(++a);

System.out.println(--a);

}

}

OUTPUT 

Explanation:

The number which we have : 20

now...

                  

                                    (a++) time                                         (a--) time

21 only  in a memory not displaying the output 21 →→→ Now we have 21 that is 

updated value in a memory so it will print 21 and →→ in a memory decrements the number from 21 

                               (++a) time

to 20 →→→Now we have 20 in a memory so it will increment the value and then print the

 incremented value →→from 20 after increment it will print 21 and store this number in a memory  

                                        (--a) time

→→→Now we have 21 in a memory so it will decrement the value and then print the decremented

 value →→from 21 after decrement it will print 20 and store this number in a memory .