If I will write
String s=new String("XYZ");
String s1=new String("XYZ");
if(s.equals(s1)){
sop("True");
}
else{
sop("False");
}
This program will give me "True".
But When I am creating my own class suppose
class Employee{
public Employee(String name);
}
Employee e= new Employee("XYZ");
Employee e1 = neew Employee("XYZ");
if(e.equals(e1)){
sop("True");
}
else{
sop("False");
}
Then it will give the output as "False".
Can I know what is happening internally?
Answers were Sorted based on User's Feedback
Answer / ashish singh
String and other wrapper classes override equals() method of object class. SO when we compare it gives the appropriate result. while the employee class did not do it.
| Is This Answer Correct ? | 10 Yes | 0 No |
Answer / sindhu
in the first case equals method compares the sequence of characters pointed by s and s1. as both are same it returns true. in the second case it is comparing the references i.e addresses of objects e and e1. as both are not same, it returns false.
| Is This Answer Correct ? | 11 Yes | 4 No |
Answer / prachi
Equals() method of Qbject class checks whether reference id's are same or not.if overridden then it will check for the value contained in those reference id's.String class has overridden equals() so it checks for the value whereas Employee class hasn't so Object class' method runs and reference id's are compared.
| Is This Answer Correct ? | 2 Yes | 0 No |
Answer / k.packiya lakshmi
In String we can write a string in double quotes and equals is
one method of string but when we creating class it doesn't
know the method of equals.
| Is This Answer Correct ? | 3 Yes | 3 No |
Answer / vikas
Extending Ashish Singh's answer, If you want employee to return true for the use case you have mentioned, override your equals and hashcode method and check only for the String object that you have in employee class in your overridden equals method. It'll return true.
| Is This Answer Correct ? | 0 Yes | 0 No |
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