/**
* Returns a new {@code Hashtable} with the same key/value pairs, capacity and load factor.
*
* @return a shallow copy of this {@code Hashtable}.
* @see java.lang.Cloneable
*/
@SuppressWarnings("unchecked")
@Override
public synchronized Object clone() {
/*
* This could be made more efficient. It unnecessarily hashes all of
* the elements in the map.
*/
Hashtable<K, V> result;
try {
result = (Hashtable<K, V>) super.clone();
} catch (CloneNotSupportedException e) {
throw new AssertionError(e);
}
// Restore clone to empty state, retaining our capacity and threshold
result.makeTable(table.length);
result.size = 0;
result.keySet = null;
result.entrySet = null;
result.values = null;
result.constructorPutAll(this);
return result;
}
/**
* Constructs a new instance of {@code Hashtable} containing the mappings from the specified map.
*
* @param map the mappings to add.
*/
public Hashtable(Map<? extends K, ? extends V> map) {
this(capacityForInitSize(map.size()));
constructorPutAll(map);
}