| package jp.ac.kobe_u.cs.prolog.builtin; |
| import jp.ac.kobe_u.cs.prolog.lang.*; |
| import java.util.Hashtable; |
| /** |
| * <code>hash_clear/1</code><br> |
| * @author Mutsunori Banbara (banbara@kobe-u.ac.jp) |
| * @author Naoyuki Tamura (tamura@kobe-u.ac.jp) |
| * @version 1.0 |
| */ |
| public class PRED_hash_clear_1 extends Predicate { |
| |
| public Term arg1; |
| |
| public PRED_hash_clear_1(Term a1, Predicate cont) { |
| arg1 = a1; |
| this.cont = cont; |
| } |
| |
| public PRED_hash_clear_1(){} |
| |
| public void setArgument(Term[] args, Predicate cont) { |
| arg1 = args[0]; |
| this.cont = cont; |
| } |
| |
| public int arity() { return 1; } |
| |
| public String toString() { |
| return "hash_clear(" + arg1 + ")"; |
| } |
| |
| public Predicate exec(Prolog engine) { |
| engine.setB0(); |
| Term a1; |
| a1 = arg1; |
| |
| 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(); |
| } else if (a1.isJavaObject()) { |
| hash = ((JavaObjectTerm) a1).object(); |
| } else { |
| throw new IllegalDomainException(this, 1, "hash_or_alias", a1); |
| } |
| if (! (hash instanceof HashtableOfTerm)) |
| throw new InternalException(this + ": Hash is not HashtableOfTerm"); |
| ((HashtableOfTerm) hash).clear(); |
| return cont; |
| } |
| } |