Using a Set with one Class but find with a String

Question

I have a Java Set<MyClass> on which I've overridden equals and hashCode to use the String name; variable.

public class MyClass{
    final String name;
    public boolean equals(Object o){...}
    public int hashCode(){return name.hashCode();}
}

Is there anyway I can get my Object out of the HashSet using something like

MyClass o = set.get("nameofmyobject");

Is there a way to do this in Java, or a datastructure? or do I need to change up all of my Sets to Maps?

Answer 1

No. You need to change to a Map. None of the methods of Set return an element.

Addendum A
If you don't care about speed you can always search manually:

MyClass find(String name, Set<MyClass> set)
{
    MyClass wrapper = new MyClass(name);
    for (MyClass e : set) {
        if (wrapper.equals(e)) {
            return e;
        }
    }
    return null;
}

Addendum B
If you use a TreeSet you can use floor:

MyClass find(String name, TreeSet<MyClass> set)
{
    MyClass wrapper = new MyClass(name);
    MyClass candidate = set.floor(wrapper);
    if (candidate != null && wrapper.equals(candidate)) {
        return candidate;
    } else {
        return null;
    }
}

Answer 2

Have a look at this question. The answer is no. Sets are not for getting elements, but to look for equality. Use a Map or List insteed.

Answer 3

As Tim said you can't. And if so you would have to call it like set.get(myClassInstance); and not set.get(some member of the stored instance)

Use

   Map<String, MyClass> myMap = new HashMap<String, MyClass>();