| package jp.ac.kobe_u.cs.prolog.builtin; |
| import jp.ac.kobe_u.cs.prolog.lang.*; |
| import java.lang.reflect.*; |
| /** |
| * <code>'$call'/2</code><br> |
| * @author Mutsunori Banbara (banbara@kobe-u.ac.jp) |
| * @author Naoyuki Tamura (tamura@kobe-u.ac.jp) |
| * @version 1.0 |
| */ |
| class PRED_$call_2 extends Predicate { |
| Term arg1, arg2; |
| Predicate cont; |
| public static SymbolTerm SYM_SLASH_2 = SymbolTerm.makeSymbol("/", 2); |
| |
| public PRED_$call_2() {} |
| public PRED_$call_2(Term a1, Term a2, Predicate cont) { |
| arg1 = a1; |
| arg2 = a2; |
| this.cont = cont; |
| } |
| |
| public void setArgument(Term args[], Predicate cont) { |
| arg1 = args[0]; |
| arg2 = args[1]; |
| this.cont = cont; |
| } |
| |
| public int arity() { return 2; } |
| |
| public String toString() { return "$call(" + arg1 + "," + arg2 + ")"; } |
| |
| public Predicate exec(Prolog engine) { |
| engine.setB0(); |
| Term a1, a2; |
| a1 = arg1.dereference(); // a1 must be atom of package name |
| a2 = arg2.dereference(); // a2 must be callable name |
| |
| String functor; |
| int arity; |
| Term[] args; |
| Class clazz; |
| Constructor constr; |
| Predicate pred; |
| |
| try { |
| if (! a1.isSymbol()) |
| throw new IllegalTypeException(this, 1, "atom", a1); |
| if (a2.isSymbol()) { |
| functor = ((SymbolTerm)a2).name(); |
| args = null; |
| arity = 0; |
| } else if (a2.isStructure()) { |
| functor = ((StructureTerm)a2).functor().name(); |
| args = ((StructureTerm)a2).args(); |
| arity = ((StructureTerm)a2).arity(); |
| } else { |
| throw new IllegalTypeException(this, 2, "callable", a2); |
| } |
| try { |
| clazz = engine.pcl.loadPredicateClass(((SymbolTerm)a1).name(), functor, arity, true); |
| } catch (ClassNotFoundException e) { |
| try { |
| clazz = engine.pcl.loadPredicateClass("jp.ac.kobe_u.cs.prolog.builtin", functor, arity, true); |
| } catch (ClassNotFoundException ee) { |
| if ((engine.getUnknown()).equals("fail")) |
| return engine.fail(); |
| Term[] fa = {SymbolTerm.makeSymbol(functor), new IntegerTerm(arity)}; |
| throw new ExistenceException(this, 0, "procedure", new StructureTerm(SYM_SLASH_2, fa), ""); |
| } |
| } |
| constr = clazz.getConstructor(); |
| constr.setAccessible(true); |
| pred = (Predicate)constr.newInstance(); |
| pred.setArgument(args, cont); |
| return pred; |
| } catch (NoSuchMethodException e) { |
| throw new SystemException(e.toString() + " in " + this.toString()); |
| } catch (InstantiationException e) { |
| throw new SystemException(e.toString() + " in " + this.toString()); |
| } catch (IllegalAccessException e) { |
| throw new SystemException(e.toString() + " in " + this.toString()); |
| } catch (SecurityException e) { |
| throw new SystemException(e.toString() + " in " + this.toString()); |
| } catch (IllegalArgumentException e) { |
| throw new SystemException(e.toString() + " in " + this.toString()); |
| } catch (InvocationTargetException e) { |
| throw new SystemException(e.toString() + " in " + this.toString()); |
| } |
| } |
| } |
| |
| |