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hashmapequalshashcode

Why equals and hashcode is not impacting hashmap size

I am trying a test with hashmap for a custom class with overridden equals and hashcode method:

public class Car {

public int hashcode() {
    return 1;
}

@Override
public boolean equals(Object o1) {
    return true;
}
}

Main Class:

public static void main(String[] args) {
    // TODO Auto-generated method stub
    HashMap<Car,String> map = new HashMap<Car,String>();
    Car c1 = new Car();
    Car c2 = new Car();
    System.out.println(c2.equals(c1));
    System.out.println(c1==c2);
    map.put(c1, "car1");
    map.put(c2, "car2");
    System.out.println(map.size());
    System.out.println(map.get(c1));
}

I expected the output as 1 and car2 but it's 2 and car1. Can anyone explain reason. My Equals is true for each car object and hashcode is also same.

Thanks,

Solution

  • It was a typo.hashcode is not overridden.I created a method hashcode() instead of hashCode(). Correcting that provided the expected result.