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Java.lang Class - Programming

Q1:

What will be the output of the program? 
String s = 'hello'; 
Object o = s; 
if( o.equals(s) )
{
    System.out.println('A'); 
} 
else
{
    System.out.println('B'); 
} 
if( s.equals(o) )
{
    System.out.println('C'); 
} 
else
{ 
    System.out.println('D'); 
}
  1. A
  2. B
  3. C
  4. D

A 1 and 3

B 2 and 4

C 3 and 4

D 1 and 2

ANS:A - 1 and 3

.equals() is used for content comparison in String.
So String creates one object of scp with reference of s.

Here String reference is assigns to Object.
So Object and String references are both poining to same content "hello".

The (o.equals(s))and (s.equals(o) checks content of 's' and 'o'.
The content is same it returns True.