public Operation exec(Prolog engine) {
engine.requireFeature(Prolog.Feature.JAVA_REFLECTION, this, arg1);
engine.setB0();
Term a1, a2, a3;
a1 = arg1;
a2 = arg2;
a3 = arg3;
Class clazz = null;
Object instance = null;
Field field = null;
Object value = null;
try {
// 1st. argument (atom or java term)
a1 = a1.dereference();
if (a1.isVariable()) {
throw new PInstantiationException(this, 1);
} else if (a1.isSymbol()) { // class
clazz = Class.forName(((SymbolTerm) a1).name());
} else if (a1.isJavaObject()) { // instance
instance = ((JavaObjectTerm) a1).object();
clazz = ((JavaObjectTerm) a1).getClazz();
} else {
throw new IllegalTypeException(this, 1, "atom_or_java", a1);
}
// 2nd. argument (atom)
a2 = a2.dereference();
if (a2.isVariable()) {
throw new PInstantiationException(this, 2);
} else if (!a2.isSymbol()) {
throw new IllegalTypeException(this, 2, "atom", a2);
}
field = clazz.getDeclaredField(((SymbolTerm) a2).name());
// 3rd. argument (term)
a3 = a3.dereference();
if (a3.isJavaObject()) value = a3.toJava();
else value = a3;
field.setAccessible(true);
field.set(instance, value);
return cont;
} catch (ClassNotFoundException e) { // Class.forName
throw new JavaException(this, 1, e);
} catch (NoSuchFieldException e) { // Class.getField(..)
throw new JavaException(this, 2, e);
} catch (SecurityException e) { // Class.getField(..)
throw new JavaException(this, 2, e);
} catch (NullPointerException e) { // Class.getField(..)
throw new JavaException(this, 2, e);
} catch (IllegalAccessException e) { // Field.get(..)
throw new JavaException(this, 2, e);
} catch (IllegalArgumentException e) { // Field.get(..)
throw new JavaException(this, 2, e);
}
}