pure interface of interface java.util.Map<A, B>

public interface Map<A, B>
{
    public abstract int size();
    public abstract boolean isEmpty();
    public abstract boolean containsKey(A key);
    public abstract boolean containsValue(B value);
    public abstract B get(A key);
    public abstract B put(A key,
                          B value);
    public abstract B remove(A key);
    public abstract void putAll(Map<A, B> t);
    public abstract void clear();
    public abstract Set<A> keySet();
    public abstract Collection<B> values();
    public abstract Set<Entry<A, B>> entries();
    public interface Entry<A, B>
    public abstract boolean equals(Object o);
    public abstract int hashCode();
}