Practice

琥珀川

Q-1:
[hashcode & equals ]

clss Sortof{
String name;
int bal;
String code;
short rate;
public int hashCode() {
return (code.length() * bal);
}
public boolean equals(Object o) {
// insert code
}
}
Which of the following would fulfill the equals() and hashCode() contracts of the class?
A & B irrelevant
C. return ((SortOf)o).code.length() * ((SortOf)o).bal == this.code.length()* this.bal;
D. return ((SortOf)o).code.length() * ((SortOf)o).bal * ((SortOf)o).rate== this.code.length()* this.bal * this.rate;
The answer given is "C"

Note:

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