blob: 37877df69cd618ad6e21f624bb3d45883e3a7d86 [file] [log] [blame]
package com.googlecode.prolog_cafe.builtin;
import com.googlecode.prolog_cafe.lang.*;
import java.lang.reflect.*;
/**
* <code>java_declared_method0/3</code>
* @author Mutsunori Banbara (banbara@kobe-u.ac.jp)
* @author Naoyuki Tamura (tamura@kobe-u.ac.jp)
* @version 1.1
*/
public class PRED_java_declared_method0_3 extends JavaPredicate {
Term arg1, arg2, arg3;
public PRED_java_declared_method0_3(Term a1, Term a2, Term a3, Operation cont) {
arg1 = a1;
arg2 = a2;
arg3 = a3;
this.cont = cont;
}
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;
Method[] methods = null;
Method m = null;
Object value = null;
int arity;
Term[] pArgs = null;
Object[] jArgs = null;
String methodName = null;
// 3rd. argument (unbound variable)
a3 = a3.dereference();
if (! a3.isVariable())
throw new IllegalTypeException(this, 3, "variable", a3);
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 or callable term)
a2 = a2.dereference();
if (a2.isVariable()) {
throw new PInstantiationException(this, 2);
} else if (a2.isSymbol()) { // No argument method
m = clazz.getDeclaredMethod(((SymbolTerm)a2).name());
m.setAccessible(true);
value = m.invoke(instance);
} else if (a2.isStructure()) { // Parameterized method
methodName = ((StructureTerm)a2).name();
arity = ((StructureTerm)a2).arity();
methods = clazz.getDeclaredMethods();
if (methods.length == 0)
throw new ExistenceException(this, 2, "method", a2, "");
pArgs = ((StructureTerm)a2).args();
jArgs = new Object[arity];
for (int i=0; i<arity; i++) {
pArgs[i] = pArgs[i].dereference();
if (! pArgs[i].isJavaObject())
pArgs[i] = new JavaObjectTerm(pArgs[i]);
jArgs[i] = pArgs[i].toJava();
}
for (int i=0; i<methods.length; i++) {
if (methods[i].getName().equals(methodName)
&& checkParameterTypes(methods[i].getParameterTypes(), pArgs)) {
try {
m = methods[i];
m.setAccessible(true);
value = m.invoke(instance, jArgs);
break; // Succeeds to invoke the method
} catch (Exception e) {
m = null; // Back to loop
}
}
}
if (m == null)
throw new ExistenceException(this, 2, "method", a2, "");
} else {
throw new IllegalTypeException(this, 2, "callable", a2);
}
if (value == null)
return cont;
if (! a3.unify(toPrologTerm(value), engine.trail))
return engine.fail();
return cont;
} catch (ClassNotFoundException e) { // Class.forName
throw new JavaException(this, 1, e);
} catch (NoSuchMethodException e) { // Class.getDeclaredMethod
throw new JavaException(this, 2, e);
} catch (SecurityException e) { // Class.getDeclaredMethods
throw new JavaException(this, 2, e);
} catch (IllegalAccessException e) { // Method.invoke
throw new JavaException(this, 2, e);
} catch (IllegalArgumentException e) { // Method.invoke
throw new JavaException(this, 2, e);
} catch (InvocationTargetException e) { // Method.invoke
throw new JavaException(this, 2, e);
} catch (NullPointerException e) { // Method.invoke
throw new JavaException(this, 2, e);
}
}
private Term toPrologTerm(Object obj) {
if (Term.instanceOfTerm(obj))
return (Term)obj;
else
return new JavaObjectTerm(obj);
}
}