Object hash = null;
a1 = a1.dereference();
if (a1.isVariable()) {
throw new PInstantiationException(this, 1);
} else if (a1.isSymbol()) {
if (!engine.getHashManager().containsKey(a1)) {
throw new ExistenceException(this, 1, "hash", a1, "");
}
hash = ((JavaObjectTerm) engine.getHashManager().get(a1)).object();