/**
 * AmbientTalk/2 Project
 * SymbiosisTest.java created on 13-nov-2006 at 15:10:58
 * (c) Programming Technology Lab, 2006 - 2007
 * Authors: Tom Van Cutsem & Stijn Mostinckx
 * 
 * Permission is hereby granted, free of charge, to any person
 * obtaining a copy of this software and associated documentation
 * files (the "Software"), to deal in the Software without
 * restriction, including without limitation the rights to use,
 * copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the
 * Software is furnished to do so, subject to the following
 * conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
 * OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
 * OTHER DEALINGS IN THE SOFTWARE.
 */
package edu.vub.at.objects.symbiosis;

import edu.vub.at.AmbientTalkTest;
import edu.vub.at.eval.Evaluator;
import edu.vub.at.exceptions.InterpreterException;
import edu.vub.at.exceptions.XArityMismatch;
import edu.vub.at.exceptions.XClassNotFound;
import edu.vub.at.exceptions.XDuplicateSlot;
import edu.vub.at.exceptions.XIllegalOperation;
import edu.vub.at.exceptions.XNotInstantiatable;
import edu.vub.at.exceptions.XSelectorNotFound;
import edu.vub.at.exceptions.XSymbiosisFailure;
import edu.vub.at.exceptions.XTypeMismatch;
import edu.vub.at.exceptions.XUnassignableField;
import edu.vub.at.objects.ATClosure;
import edu.vub.at.objects.ATField;
import edu.vub.at.objects.ATMethod;
import edu.vub.at.objects.ATObject;
import edu.vub.at.objects.ATTypeTag;
import edu.vub.at.objects.natives.NATContext;
import edu.vub.at.objects.natives.NATException;
import edu.vub.at.objects.natives.NATFraction;
import edu.vub.at.objects.natives.NativeATObject;
import edu.vub.at.objects.natives.OBJNil;
import edu.vub.at.objects.natives.NATNumber;
import edu.vub.at.objects.natives.NATObject;
import edu.vub.at.objects.natives.NATTable;
import edu.vub.at.objects.natives.NATText;
import edu.vub.at.objects.natives.grammar.AGAssignmentSymbol;
import edu.vub.at.objects.natives.grammar.AGSymbol;
import edu.vub.at.objects.natives.grammar.TestEval;

import java.io.Serializable;
import java.util.Collection;
import java.util.List;
import java.util.Set;
import java.util.Vector;

/**
 * Tests the symbiosis with Java. This is primarily done by wrapping
 * the SymbiosisTest class and instances itself and invoking some of
 * their non-test prefixed methods.
 * 
 * @author tvcutsem
 */
public class SymbiosisTest extends AmbientTalkTest {
	
	public static void main(String[] args) {
		junit.swingui.TestRunner.run(SymbiosisTest.class);
		/*Test test= new SymbiosisTest() {
		        public void runTest() throws Exception {
		        	  testBugfixOverloadedConstructor();
		        }
		 };
		 junit.textui.TestRunner.run(test);*/
	}
	
	// test fixture
	private Class jTestClass;
	private JavaClass atTestClass;
	
	private SymbiosisTest jTestObject;
	private JavaObject atTestObject;
	
	private JavaPackage jLobby_;
	
	// these fields and methods will be reflectively invoked from within AmbientTalk
	public int xtest;
	public static String ytest = "AmbientTalk";
	
	public SymbiosisTest(int xval) {
		xtest = xval;
	}
	
	public SymbiosisTest() {
		xtest = 0;
	}

	public SymbiosisTest(SymbiosisTest t) {
		xtest = -1;
	}
	
	public SymbiosisTest(AmbientTalkTest t) {
		xtest = -1;
	}
	
	private static class ExceptionTest extends Exception {
		private static final long serialVersionUID = 1L;
	}

	public SymbiosisTest(JavaClass c) throws ExceptionTest {
		throw new ExceptionTest();
	}
	
	public static final int TEST_OBJECT_INIT = 42;
	
	public int gettertest() { return xtest; }
	public void settertest(int xval) { xtest = xval; }
	public static String prefix(String msg) { return msg + ytest; }
	public boolean identitytest(Object obj) { return obj == this; }
	
	public String overloadedtest() { return "()"; }
	public String overloadedtest(int x) { return "(int)"; }
	public String overloadedtest(Object[] vals) { return "(Object[])"; }
	public String overloadedtest(double x) { return "(double)"; }
	public String overloadedtest(SymbiosisTest x) { return "(SymbiosisTest)"; }
	
	public Object overloadedvararg(ATObject[] varargs) { return null; }
	public int overloadedvararg(int x) { return x; }
	
	public String overloadedmatch2(Object x) { return "(Object)"; }
	public String overloadedmatch2(SymbiosisTest x) { return "(SymbiosisTest)"; }
	
	public void setUp() {
		jTestClass = SymbiosisTest.class;
		atTestClass = JavaClass.wrapperFor(SymbiosisTest.class);
		
		jTestObject = new SymbiosisTest(TEST_OBJECT_INIT);
		atTestObject = JavaObject.wrapperFor(jTestObject);
		
		jLobby_ = new JavaPackage("");
	}
	
	/**
	 * Test the conversion function Symbiosis.ambientTalkToJava for various kinds of input.
	 */
	public void testAT2JavaConversion() {
		try {
			// -- WRAPPED JAVA OBJECTS --
			assertEquals(jTestObject, Symbiosis.ambientTalkToJava(atTestObject, SymbiosisTest.class));
			// -- PRIMITIVE TYPES --
			assertEquals(new Integer(5), Symbiosis.ambientTalkToJava(NATNumber.atValue(5), int.class));
			// -- STRINGS --
			assertEquals(ytest, Symbiosis.ambientTalkToJava(NATText.atValue(ytest), String.class));
			// -- ARRAYS --
			assertEquals(0.5, ((double[]) Symbiosis.ambientTalkToJava(NATTable.atValue(new ATObject[] { NATFraction.atValue(0.5) }), double[].class))[0], 0.0);
			// -- EXCEPTIONS --
			assertEquals(XIllegalOperation.class, Symbiosis.ambientTalkToJava(new XIllegalOperation("AT2JavaTest").getAmbientTalkRepresentation(), Exception.class).getClass());
			// -- CLASS OBJECTS --
			assertEquals(jTestClass, Symbiosis.ambientTalkToJava(atTestClass, Class.class));
			// -- nil => NULL if converting to Java --
			assertEquals(null, Symbiosis.ambientTalkToJava(OBJNil._INSTANCE_, Runnable.class));
			// -- nil => nil if remaining within AT --
			assertEquals(OBJNil._INSTANCE_, Symbiosis.ambientTalkToJava(OBJNil._INSTANCE_, ATObject.class));
			// beware with types such as java.lang.Object that match both Java and AT types!
			// if the ATObject can be assigned to the Java type, the ATObject will be kept
			assertEquals(OBJNil._INSTANCE_, Symbiosis.ambientTalkToJava(OBJNil._INSTANCE_, Object.class));
			// -- INTERFACE TYPES AND NAT CLASSES --
			assertTrue(Symbiosis.ambientTalkToJava(new NATObject(), Runnable.class) instanceof Runnable);
			try {
				Symbiosis.ambientTalkToJava(new NATObject(), Symbiosis.class);
				fail();
			} catch (XTypeMismatch e) {
				// expected: coercion does not work for non-interface class types
			}
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Test the conversion function Symbiosis.javaToAmbientTalk for various kinds of input.
	 */
	public void testJava2ATConversion() {
		try {
			// -- WRAPPED JAVA OBJECTS --
			assertEquals(atTestObject, Symbiosis.javaToAmbientTalk(jTestObject));
			// -- PRIMITIVE TYPES --
			assertEquals(NATNumber.atValue(5), Symbiosis.javaToAmbientTalk(new Integer(5)));
			// -- STRINGS --
			assertEquals(NATText.atValue(ytest), Symbiosis.javaToAmbientTalk(ytest));
			// -- ARRAYS --
			assertEquals(NATFraction.atValue(0.5), Symbiosis.javaToAmbientTalk(new double[] { 0.5 }).asNativeTable().elements_[0]);
			// -- EXCEPTIONS --
			assertEquals(XIllegalOperation.class, ((NATException)Symbiosis.javaToAmbientTalk(new XIllegalOperation("Java2ATTest"))).getWrappedException().getClass());
			// -- CLASS OBJECTS --
			assertEquals(atTestClass, Symbiosis.javaToAmbientTalk(jTestClass));
			// -- nil => NULL --
			assertEquals(OBJNil._INSTANCE_, Symbiosis.javaToAmbientTalk(null));
			// -- INTERFACE TYPES AND NAT CLASSES --
			ATObject orig = new NATObject();
			Object proxy = Symbiosis.ambientTalkToJava(orig, Runnable.class);
			assertEquals(orig, Symbiosis.javaToAmbientTalk(proxy));
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Invokes the two instance methods gettertest and settertest on atTestObject.
	 * Also performs a selection of the field 'xtest'
	 * 
	 * Also invokes the method 'identitytest' to see whether AT->Java conversion does proper unwrapping
	 */
	public void testWorkingInstanceInvocation() {
		try {
			// def result := atTestObject.gettertest(); assert(42 == result)
			ATObject result = atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("gettertest"), NATTable.EMPTY);
			assertEquals(TEST_OBJECT_INIT, result.asNativeNumber().javaValue);
			
			// result := atTestObject.settertest(1); assert(result == nil); assert(atTestObject.xtest == 1)
			result = atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("settertest"), NATTable.atValue(new ATObject[] { NATNumber.ONE }));
			assertEquals(OBJNil._INSTANCE_, result);
			assertEquals(1, jTestObject.xtest);
			// result := atTestObject.xtest
			result = atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("xtest"), NATTable.EMPTY);
			assertEquals(NATNumber.ONE, result);
			
			// atTestObject.identitytest(atTestObject) == atTestObject
			assertTrue(atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("identitytest"),
					                           NATTable.atValue(new ATObject[] { atTestObject })).asNativeBoolean().javaValue);
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}

	/**
	 * Invokes the class method 'prefix' and performs a selection and assignment of the static 'ytest' field
	 */
	public void testWorkingClassInvocation() {
		try {
			// def result := atTestClass.prefix("Hello, "); assert("Hello, " + ytest == result)
			String txt = "Hello, ";
			NATText prefix = NATText.atValue(txt);
			ATObject result = atTestClass.meta_invoke(atTestClass, AGSymbol.jAlloc("prefix"), NATTable.atValue(new ATObject[] { prefix }));
			assertEquals(txt + ytest, result.asNativeText().javaValue);
			
			// result := atTestClass.ytest; assert(result == ytest);
			result = atTestClass.meta_invoke(atTestClass, AGSymbol.jAlloc("ytest"), NATTable.EMPTY);
			assertEquals(ytest, result.asNativeText().javaValue);
			
			// atTestClass.ytest := "Hello, "; assert(ytest == "Hello, ")
			result = atTestClass.meta_invoke(atTestClass, AGAssignmentSymbol.jAlloc("ytest:="), NATTable.of(prefix));
			assertEquals(prefix, result);
			assertEquals(txt, ytest);
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}		
	}
	
	/**
	 * Invokes the method 'gettertest' with one argument instead of zero.
	 */
	public void testFaultyArity() {
		try {
			atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("gettertest"), NATTable.atValue(new ATObject[] { OBJNil._INSTANCE_ }));
			fail("Expected an arity mismatch exception");
		} catch(XArityMismatch e) {
			// expected exception: success
		} catch(InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Invokes the method 'settertest' with a double (fraction) instead of an int (number)
	 */
	public void testIllegalArgs() {
		try {
			atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("settertest"), NATTable.atValue(new ATObject[] { NATFraction.atValue(0.1) }));
			fail("Expected an illegal argument exception");
		} catch(XTypeMismatch e) {
			// Java expects an int, so AT expects a native number, but is given a native fraction
			if (e.getExpectedType() == NATNumber.class) {
				// expected exception: success
			} else {
				fail(e.getMessage());
			}
		} catch(InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tries to assign to a final public field
	 */
	public void testIllegalAssignment() {
		try {
			atTestClass.meta_invoke(atTestClass,
					AGAssignmentSymbol.jAlloc("TEST_OBJECT_INIT:="), NATTable.of(NATNumber.atValue(0)));
			fail("Expected an illegal assignment exception");
		} catch(XSelectorNotFound e) {
			// expected exception: success
		} catch(InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Test whether variable arguments work
	 */
	public void testVarArgInvocation() {
		try {
			ATObject result = atTestObject.meta_invoke(atTestObject,
													AGSymbol.jAlloc("overloadedvararg"),
													NATTable.atValue(new ATObject[] { NATNumber.ZERO, NATNumber.ONE }));
			assertEquals(OBJNil._INSTANCE_, result);
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests whether overloaded methods can be properly invoked if they can be resolved
	 * to one method using the actual arguments.
	 */
	public void testOverloadedInvWithOneMatch() {
		try {
			// invokes overloadedtest(int)
			ATObject result = atTestObject.meta_invoke(atTestObject,
													AGSymbol.jAlloc("overloadedtest"),
													NATTable.atValue(new ATObject[] { NATNumber.ZERO }));
			assertEquals("(int)", result.asNativeText().javaValue);
			// invokes overloadedtest(SymbiosisTest)
			result = atTestObject.meta_invoke(atTestObject,
											AGSymbol.jAlloc("overloadedtest"),
											NATTable.atValue(new ATObject[] { atTestObject }));
			assertEquals("(SymbiosisTest)", result.asNativeText().javaValue);
			// invokes overloadedtest()
			result = atTestObject.meta_invoke(atTestObject,
											AGSymbol.jAlloc("overloadedtest"),
											NATTable.EMPTY);
			assertEquals("()", result.asNativeText().javaValue);
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Invokes an overloaded method where the symbiosis cannot disambiguate automatically.
	 */
	public void testOverloadedInvWithMultipleMatches() {
		try {
			// invokes overloadedmatch2(Object|SymbiosisTest) => error
			atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("overloadedmatch2"),
											     NATTable.atValue(new ATObject[] { atTestObject }));
			fail("Expected a symbiosis exception");
		} catch (XSymbiosisFailure e) {
			// success: expected exception
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Invokes an overloaded method that does not match the specified argument type
	 */
	public void testOverloadedInvWithNoMatch() {
		try {
			// invokes overloadedtest(NATObject) => error
			atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("overloadedtest"),
											     NATTable.atValue(new ATObject[] { new NATObject() }));
			fail("Expected a symbiosis exception");
		} catch (XSymbiosisFailure e) {
			// success: expected exception
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Invokes a method that is not defined in the class.
	 */
	public void testNonExistentMethod() {
		try {
			// invokes foo(1) => error
			atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("foo"),
											     NATTable.atValue(new ATObject[] { NATNumber.ONE }));
			fail("Expected a selector not found exception");
		} catch (XSelectorNotFound e) {
			// success: expected exception
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests first-class field access for both instances and classes
	 */
	public void testFirstClassFields() {
		try {
			// def result := (reflect: atTestObject).grabField("xtest")
			ATField result = atTestObject.meta_grabField(AGSymbol.jAlloc("xtest")).asField();
			assertEquals("xtest", result.base_name().toString());
			assertEquals(TEST_OBJECT_INIT, result.base_readField().asNativeNumber().javaValue);
			
			// result := (reflect: atTestClass).grabField("ytest")
			result = atTestClass.meta_grabField(AGSymbol.jAlloc("ytest")).asField();
			assertEquals("ytest", result.base_name().toString());
			assertEquals(ytest, result.base_readField().asNativeText().javaValue);
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests first-class method access for both instances and classes
	 */
	public void testFirstClassMethods() {
		try {
			// def result := (reflect: atTestObject).grabMethod("gettertest")
			ATMethod result = atTestObject.meta_grabMethod(AGSymbol.jAlloc("gettertest")).asMethod();
			assertEquals("gettertest", result.base_name().toString());
			// assert (42 == result())
			assertEquals(TEST_OBJECT_INIT, result.base_apply(NATTable.EMPTY,
					new NATContext(atTestObject, atTestObject)).asNativeNumber().javaValue);
			
			// clo := atTestObject.gettertest
			ATClosure clo = atTestObject.meta_select(atTestObject, AGSymbol.jAlloc("gettertest"));
			// assert (42 == clo())
			assertEquals(TEST_OBJECT_INIT, clo.base_apply(NATTable.EMPTY).asNativeNumber().javaValue);
			
			// result := (reflect: atTestClass).grabMethod("prefix")
			result = atTestClass.meta_grabMethod(AGSymbol.jAlloc("prefix")).asMethod();
			assertEquals("prefix", result.base_name().toString());
			// assert ("AmbientTalk" == result(""))
			assertEquals(ytest, result.base_apply(NATTable.atValue(new ATObject[] { NATText.atValue("") }),
					new NATContext(atTestClass, atTestClass)).asNativeText().javaValue);	
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests casting to manually resolve overloaded method invocations
	 * Selecting a method from a Java object results in a JavaClosure instance. Such a Java
	 * closure understands the message 'cast', which allows the programmer to manually restrict
	 * the wrapped JavaMethods to specific type signatures. In this case, the two choices
	 *   overloadedmatch2(Object)
	 *   overloadedmatch2(SymbiosisTest)
	 * are manually restricted such that only the second one remains applicable
	 */
	public void testCasting() {
		try {
			// invokes overloadedmatch2(SymbiosisTest) via explicit casting
			ATClosure method = atTestObject.meta_select(atTestObject, AGSymbol.jAlloc("overloadedmatch2"));
			ATClosure castedMethod = method.meta_invoke(method, AGSymbol.jAlloc("cast"), NATTable.atValue(new ATObject[] { atTestClass })).asClosure();
			castedMethod.base_apply(NATTable.atValue(new ATObject[] { atTestObject }));
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests whether the parent pointers of the AT symbionts refer to the proper objects.
	 */
	public void testSymbiontParents() {
		try {
			// the dynamic parent of atTestObject is atTestClass
			assertEquals(atTestClass, atTestObject.base_super());
			// the dynamic parent of atTestClass is nil
			assertEquals(OBJNil._INSTANCE_, atTestClass.base_super());
			
			// the lexical parent of atTestObject is the lexical root
			assertEquals(Evaluator.getGlobalLexicalScope(), atTestObject.impl_lexicalParent());
			// the lexical parent of atTestClass is the lexical root
			assertEquals(Evaluator.getGlobalLexicalScope(), atTestClass.impl_lexicalParent());
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests whether new per-instance methods and fields can be added to a wrapped Java object.
	 */
	public void testSymbiontInstanceAdditions() {
		try {
			// (reflect: atTestObject).defineField("x", 1)
			atTestObject.meta_defineField(AGSymbol.jAlloc("x"), NATNumber.ONE);
			// assert(atTestObject.x == 1)
			assertEquals(NATNumber.ONE, atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("x"), NATTable.EMPTY));
			
			// (reflect: atTestObject).addMethod(<method:"foo",[x],{x}>)
			ATMethod foo = evalAndReturn("def foo(x) { x }; &foo").asClosure().base_method();
			atTestObject.meta_addMethod(foo);
			// assert(atTestObject.foo(0) == 0)
			assertEquals(NATNumber.ZERO, atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("foo"),
					NATTable.atValue(new ATObject[] { NATNumber.ZERO })));
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests whether no duplicate methods or fields can be added to a wrapped Java object.
	 */
	public void testSymbiontDuplicates() {
		try {
			try {
				// def atTestObject.xtest := 1
				atTestObject.meta_defineField(AGSymbol.jAlloc("xtest"), NATNumber.ONE);
				fail("expected a duplicate slot exception");
			} catch (XDuplicateSlot e) {
			    // expected exception: success
			}
			try {
				// def atTestObject.gettertest() { nil }
				ATMethod getter = evalAndReturn("def gettertest() { nil }; &gettertest").asClosure().base_method();
				atTestObject.meta_addMethod(getter);
				fail("expected a duplicate slot exception");
			} catch (XDuplicateSlot e) {
			    // expected exception: success
			}
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}

	/**
	 * Tests whether new per-class methods and fields can be added to a wrapped Java class.
	 * Also tests whether existing instances can make use of these newly added methods
	 */
	public void testSymbiontClassAdditions() {
		try {
			// (reflect: atTestClass).defineField("z", 1)
			atTestClass.meta_defineField(AGSymbol.jAlloc("z"), NATNumber.ONE);
			// assert(atTestClass.z == 1)
			assertEquals(NATNumber.ONE, atTestClass.impl_invokeAccessor(atTestClass, AGSymbol.jAlloc("z"), NATTable.EMPTY));
			// assert(aTestObject.z == 1) -> delegation to class
			assertEquals(NATNumber.ONE, atTestObject.impl_invokeAccessor(atTestObject, AGSymbol.jAlloc("z"), NATTable.EMPTY));
			
			// (reflect: atTestClass).addMethod(<method:"get",[],{self.xtest}>)
			ATMethod get = evalAndReturn("def get() { self.xtest }; &get").asClosure().base_method();
			atTestClass.meta_addMethod(get);
			// assert(atTestObject.xtest == atTestObject.get())
			assertEquals(atTestObject.impl_invokeAccessor(atTestObject, AGSymbol.jAlloc("xtest"), NATTable.EMPTY),
					     atTestObject.meta_invoke(atTestObject, AGSymbol.jAlloc("get"), NATTable.EMPTY));
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests cloning behaviour for both wrapped class instances and classes.
	 */
	public void testCloning() {
		try {
			// cloning a class results in the same class
			assertEquals(atTestClass, atTestClass.meta_clone());
			
			try {
				// cloning a java object results in an error
				atTestObject.meta_clone();
				fail("expected an illegal operation exception");
			} catch (XIllegalOperation e) {
				// expected exception: success
			}
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests the invocation of new on a wrapped Java Class.
	 * Instantiates the Java class via the default init implementation.
	 */
	public void testWorkingInstanceCreation() {
		try {
			// def instance := atTestClass.new(1)
			ATObject instance = atTestClass.meta_newInstance(NATTable.atValue(new ATObject[] { NATNumber.ONE }));
			assertEquals(JavaObject.class, instance.getClass());
			assertEquals(NATNumber.ONE, instance.meta_invoke(instance, AGSymbol.jAlloc("xtest"), NATTable.EMPTY));
			
			Object realInstance = instance.asJavaObjectUnderSymbiosis().getWrappedObject();
			assertEquals(SymbiosisTest.class, realInstance.getClass());
			assertEquals(1, ((SymbiosisTest) realInstance).xtest);
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests whether classes with private constructors terminate cleanly.
	 */
	public void testNonInstantiatableCreation() {
		try {
			// def instance := JavaObject.new(1)
			JavaClass.wrapperFor(JavaObject.class).meta_newInstance(NATTable.atValue(new ATObject[] { NATNumber.ONE }));
			fail("expected a not instantiatable exception");
		} catch (XNotInstantiatable e) {
			// expected exception: success
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests whether incorrect arguments passed to constructor terminate cleanly.
	 */
	public void testIllegalArgsInstanceCreation() {
		try {
			// def instance := atTestClass.new(1.0)
			atTestClass.meta_newInstance(NATTable.atValue(new ATObject[] { NATFraction.atValue(1.0) }));
			fail("expected a symbiosis failure with 0 matches");
		} catch (XSymbiosisFailure e) {
			// expected exception: success
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests whether overloaded constructors which cannot be resolved terminates cleanly.
	 */
	public void testOverloadedInstanceCreation() {
		try {
			// def instance := atTestClass.new(atTestObject) => 2 matches
			atTestClass.meta_newInstance(NATTable.atValue(new ATObject[] { atTestObject }));
			fail("expected a symbiosis failure with 2 matches");
		} catch (XSymbiosisFailure e) {
			// expected exception: success
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests an instance creation that raises an exception
	 */
	public void testExceptionInInstanceCreation() {
		try {
			// def instance := atTestClass.new(atTestClass)
			atTestClass.meta_newInstance(NATTable.atValue(new ATObject[] { atTestClass }));
			fail("expected the constructor to throw an exception");
		} catch (XJavaException e) {
			// expected exception: success if it was an ExceptionTest instance
			assertEquals(ExceptionTest.class, e.getWrappedJavaException().getClass());
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests the invocation of new on a wrapped Java Object, rather than on a Java Class.
	 */
	public void testCreationViaJavaObject() {
		try {
			// def instance := atTestObject.new(55)
			ATObject instance = atTestObject.meta_newInstance(
					NATTable.atValue(new ATObject[] { NATNumber.atValue(55) }));
			
			assertEquals(55, instance.impl_invokeAccessor(instance, AGSymbol.jAlloc("xtest"), NATTable.EMPTY).asNativeNumber().javaValue);
			assertEquals(atTestClass, instance.base_super());
			assertEquals(jTestObject.xtest, atTestObject.impl_invokeAccessor(atTestObject,
					AGSymbol.jAlloc("xtest"), NATTable.EMPTY).asNativeNumber().javaValue);
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests the invocation of new on a wrapped Java Class.
	 * Instantiates the Java class via a custom new implementation.
	 * 
	 * BEWARE: this test should be the last for testing symbiotic instance creation as it
	 * MODIFIES the test fixture (the JavaClass wrapper object)! Ths is because the JavaClass wrapper
	 * is pooled and reused throughout subsequent tests.
	 */
	public void testCustomInstanceCreation() {
		try {
			// def orignew := atTestClass.new; def atTestClass.new(x,y) { def o := orignew(x); def o.ytest := y; o }
			ATClosure newClo = evalAndReturn("def new(x,y) { def o := orignew(x); def o.ytest := y; o }; &new").asClosure();
			atTestClass.meta_defineField(AGSymbol.jAlloc("orignew"), atTestClass.meta_select(atTestClass, AGSymbol.jAlloc("new")));
			atTestClass.meta_addMethod(newClo.base_method());
			
			// def instance := atTestClass.new(10, 11)
			ATObject instance = atTestClass.meta_invoke(atTestClass, AGSymbol.jAlloc("new"),
					NATTable.atValue(new ATObject[] { NATNumber.atValue(10), NATNumber.atValue(11) }));
			
			assertEquals(10, instance.impl_invokeAccessor(instance, AGSymbol.jAlloc("xtest"), NATTable.EMPTY).asNativeNumber().javaValue);
			assertEquals(11, instance.impl_invokeAccessor(instance, AGSymbol.jAlloc("ytest"), NATTable.EMPTY).asNativeNumber().javaValue);
		} catch (InterpreterException e) {
			fail(e.getMessage());
		}
	}
	
	/**
	 * Tests whether jlobby.java results in a new JavaPackage.
	 * Tests whether jlobby.java.lang results in a new JavaPackage.
	 * Tests whether jlobby.java.lang.Object results in the proper loading of that class
	 */
	public void testJLobbyPackageLoading() throws InterpreterException {
		ATObject jpkg = jLobby_.impl_invokeAccessor(jLobby_, AGSymbol.jAlloc("java"), NATTable.EMPTY);
		assertEquals(JavaPackage.class, jpkg.getClass());
		assertTrue(jLobby_.meta_respondsTo(AGSymbol.jAlloc("java")).asNativeBoolean().javaValue);
		ATObject jlpkg = jpkg.impl_invokeAccessor(jpkg, AGSymbol.jAlloc("lang"), NATTable.EMPTY);
		assertEquals(JavaPackage.class, jlpkg.getClass());
		assertTrue(jpkg.meta_respondsTo(AGSymbol.jAlloc("lang")).asNativeBoolean().javaValue);
		ATObject jObject = jlpkg.impl_invokeAccessor(jlpkg, AGSymbol.jAlloc("Object"), NATTable.EMPTY);
		assertEquals(JavaClass.class, jObject.getClass());
		assertTrue(jlpkg.meta_respondsTo(AGSymbol.jAlloc("Object")).asNativeBoolean().javaValue);
	}
	
	/**
	 * Tests whether lowercase classes can be loaded via the class method of a JavaPackage.
	 */
	public void testJLobbyExplicitClassLoading() throws InterpreterException {
		ATObject eduVubAtObjectsSymbiosisPkg = new JavaPackage("edu.vub.at.objects.symbiosis.");

		// load the class manually: invoke pkg.class("lowercaseClassTest")
		ATObject cls = eduVubAtObjectsSymbiosisPkg.meta_invoke(
				eduVubAtObjectsSymbiosisPkg,
				AGSymbol.jAlloc("class"),
				NATTable.atValue(new ATObject[] { AGSymbol.jAlloc("lowercaseClassTest") }));
		assertEquals(JavaClass.class, cls.getClass());
		assertTrue(eduVubAtObjectsSymbiosisPkg.meta_respondsTo(
				    AGSymbol.jAlloc("lowercaseClassTest")).asNativeBoolean().javaValue);
	}
	
	/**
	 * Tests whether access to a nonexistent class gives rise to a selector not found exception.
	 */
	public void testJLobbyNonexistentClassLoading() throws InterpreterException {
		try {
			jLobby_.impl_invokeAccessor(jLobby_, AGSymbol.jAlloc("Foo"), NATTable.EMPTY);
			fail("expected a class not found exception");
		} catch (XClassNotFound e) {
			// success: expected exception
		}
	}
	
	/**
	 * Tests whether the uppercase package 'foo.Bar' can be loaded via the package method of a JavaPackage.
	 */
	public void testJLobbyExplicitPackageLoading() throws InterpreterException {
		// def fooPkg := jLobby.foo;
		ATObject fooPkg = jLobby_.impl_invokeAccessor(jLobby_, AGSymbol.jAlloc("foo"), NATTable.EMPTY);
		// def BarPkg := foo.package(`Bar);
		ATObject BarPkg = fooPkg.meta_invoke(fooPkg,
										   AGSymbol.jAlloc("package"),
										   NATTable.atValue(new ATObject[] { AGSymbol.jAlloc("Bar") }));
		assertEquals(JavaPackage.class, BarPkg.getClass());
		assertTrue(fooPkg.meta_respondsTo(AGSymbol.jAlloc("Bar")).asNativeBoolean().javaValue);
	}
	
	/**
	 * BUGFIX TEST: jlobby.java.lang.StringBuffer.new(10) failed to discriminate between constructors
	 * StringBuffer(String) and StringBuffer(int), reason was that anything native was convertible to
	 * NATText and also to String. Fixed by reimplementing asNativeText in {@link NativeATObject}
	 * to throw a type exception as usual.
	 * 
	 * This constructor is yet again overloaded starting from Java 1.5 because StringBuffer
	 * now also defines the constructor StringBuffer(CharSequence). Because CharSequence is
	 * an interface it can be satisfied by any AmbientTalk object. Hence,
	 * the method must be explicitly cast.
	 * 
	 * Currently, the test is commented out because we cannot cast constructors of Java methods
	 * (selecting new returns a native closure, not a javaclosure which we can cast)
	 */
	/* public void testBugfixOverloadedConstructor() throws InterpreterException {
		// def jStringBuffer := jLobby.java.lang.StringBuffer;
		ATObject jStringBuffer = JavaClass.wrapperFor(StringBuffer.class);
		// jStringBuffer.new(10)
		jStringBuffer.meta_invoke(jStringBuffer, AGSymbol.jAlloc("new"), NATTable.atValue(new ATObject[] { NATNumber.atValue(10) }));
	} */
	
	/**
	 * Tests whether Java interface types are correctly treated as AT/2 types.
	 * Test cases: interface java.util.Set extends java.util.Collection
	 */
	public void testInterfacesAndTypes() throws InterpreterException {
		JavaClass jSet = JavaClass.wrapperFor(Set.class);
		JavaClass jCollection = JavaClass.wrapperFor(Collection.class);
		ATTypeTag atSet = jSet.asTypeTag();
		ATTypeTag atCollection = jCollection.asTypeTag();
		// type name = 'java.util.Set'
		assertEquals(AGSymbol.jAlloc("java.util.Set"), atSet.base_typeName());
		// type parents = [ java.util.Collection ]
		assertEquals(jCollection, atSet.base_superTypes().base_at(NATNumber.ONE));
		// Set isSubtypeOf Collection? true
		assertTrue(atSet.base_isSubtypeOf(atCollection).asNativeBoolean().javaValue);
		// Collection isSubtypeOf Set? false
		assertFalse(atCollection.base_isSubtypeOf(atSet).asNativeBoolean().javaValue);
		// Set isSubtypeOf Set? true
		assertTrue(atSet.base_isSubtypeOf(atSet).asNativeBoolean().javaValue);
	}
	
	/**
	 * Test whether JavaObject wrappers are correctly typed with all
	 * of the interfaces of the wrapped instance's class.
	 * 
	 * Test case: java.util.Vector implements List, RandomAccess, Cloneable, Serializable
	 */
	public void testTypedJavaObject() throws InterpreterException {
		JavaClass jVector = JavaClass.wrapperFor(Vector.class);
		JavaObject vec = jVector.meta_newInstance(NATTable.EMPTY).asJavaObjectUnderSymbiosis();
		
		ATTypeTag jListType = JavaClass.wrapperFor(List.class).asTypeTag();
		ATTypeTag jCollectionType = JavaClass.wrapperFor(Collection.class).asTypeTag();
		ATTypeTag jSerializableType = JavaClass.wrapperFor(Serializable.class).asTypeTag();
		ATTypeTag jSetType = JavaClass.wrapperFor(Set.class).asTypeTag();
		
		// vec is tagged with List? true
		assertTrue(vec.meta_isTaggedAs(jListType).asNativeBoolean().javaValue);
		// vec is tagged with Collection? true
		assertTrue(vec.meta_isTaggedAs(jCollectionType).asNativeBoolean().javaValue);
		// vec is tagged with Serializable? true
		assertTrue(vec.meta_isTaggedAs(jSerializableType).asNativeBoolean().javaValue);
		// vec is tagged with Set? false
		assertFalse(vec.meta_isTaggedAs(jSetType).asNativeBoolean().javaValue);
	}
	
}

class lowercaseClassTest { }