package com.sun.source.util;

import java.util.Objects;

public abstract class AbstractSet<E> extends AbstractCollection<E> implements Set<E>

{

protected AbstractSet() {

}

public boolean equals(Object o) {

if(o==this)

return true;

if(!(o instanceof Set))

return false;

Collection<?> c=(Collection<?>) o;

if(c.size()!=this.size())

return false;

try

{

return containsAll(c);

} catch (ClassCastException unused) {

return false;

} catch (NullPointerException unused) {

return false;

}

}

public int hashCode() {

int h=0;

Iterator<E> it=iterator();

while(it.hasNext()) {

E e=it.next();

if(e!=null)

h+=e.hashCode();

}

return h;

}

public boolean removeAll(Collection<?> c) {

Objects.requireNonNull(c);

boolean modified=false;

if(this.size()>c.size()) {

for(Iterator<?> it=this.iterator();it.hasNext();) {

modified|=remove(it.next());

}

}else {

for(Iterator<?> it=iterator();it.hasNext();) {

if(c.contains(it.next())) {

it.remove();

modified=true;

}

}

}

return modified;

}

}