/*
Copyright 2009-2013 Attila Szegedi
Licensed under both the Apache License, Version 2.0 (the "Apache License")
and the BSD License (the "BSD License"), with licensee being free to
choose either of the two at their discretion.
You may not use this file except in compliance with either the Apache
License or the BSD License.
If you choose to use this file in compliance with the Apache License, the
following notice applies to you:
You may obtain a copy of the Apache License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
implied. See the License for the specific language governing
permissions and limitations under the License.
If you choose to use this file in compliance with the BSD License, the
following notice applies to you:
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are
met:
* Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.
* Redistributions in binary form must reproduce the above copyright
notice, this list of conditions and the following disclaimer in the
documentation and/or other materials provided with the distribution.
* Neither the name of the copyright holder nor the names of
contributors may be used to endorse or promote products derived from
this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL COPYRIGHT HOLDER
BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package org.dynalang.dynalink.beans;
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.lang.reflect.Array;
import java.util.Arrays;
import java.util.Collection;
import org.dynalang.dynalink.CallSiteDescriptor;
import org.dynalang.dynalink.beans.GuardedInvocationComponent.ValidationType;
import org.dynalang.dynalink.linker.GuardedInvocation;
import org.dynalang.dynalink.linker.LinkRequest;
import org.dynalang.dynalink.linker.LinkerServices;
import org.dynalang.dynalink.linker.TypeBasedGuardingDynamicLinker;
import org.dynalang.dynalink.support.Lookup;
/**
* Provides a linker for the {@link StaticClass} objects.
* @author Attila Szegedi
*/
class StaticClassLinker implements TypeBasedGuardingDynamicLinker {
private static final ClassValue<SingleClassStaticsLinker> linkers = new ClassValue<SingleClassStaticsLinker>() {
@Override
protected SingleClassStaticsLinker computeValue(Class<?> clazz) {
return new SingleClassStaticsLinker(clazz);
}
};
private static class SingleClassStaticsLinker extends AbstractJavaLinker {
private final DynamicMethod constructor;
SingleClassStaticsLinker(Class<?> clazz) {
super(clazz, IS_CLASS.bindTo(clazz));
// Map "staticClassObject.class" to StaticClass.getRepresentedClass(). Some adventurous soul could subclass
// StaticClass, so we use INSTANCE_OF validation instead of EXACT_CLASS.
setPropertyGetter("class", GET_CLASS, ValidationType.INSTANCE_OF);
constructor = createConstructorMethod(clazz);
}
/**
* Creates a dynamic method containing all overloads of a class' public constructor
* @param clazz the target class
* @return a dynamic method containing all overloads of a class' public constructor. If the class has no public
* constructors, returns null.
*/
private static DynamicMethod createConstructorMethod(Class<?> clazz) {
if(clazz.isArray()) {
final MethodHandle boundArrayCtor = ARRAY_CTOR.bindTo(clazz.getComponentType());
return new SimpleDynamicMethod(StaticClassIntrospector.editConstructorMethodHandle(
boundArrayCtor.asType(boundArrayCtor.type().changeReturnType(clazz))), clazz, "<init>");
}
if(CheckRestrictedPackage.isRestrictedClass(clazz)) {
return null;
}
return createDynamicMethod(Arrays.asList(clazz.getConstructors()), clazz, "<init>");
}
@Override
FacetIntrospector createFacetIntrospector() {
return new StaticClassIntrospector(clazz);
}
@Override
public GuardedInvocation getGuardedInvocation(LinkRequest request, LinkerServices linkerServices)
throws Exception {
final GuardedInvocation gi = super.getGuardedInvocation(request, linkerServices);
if(gi != null) {
return gi;
}
final CallSiteDescriptor desc = request.getCallSiteDescriptor();
final String op = desc.getNameToken(CallSiteDescriptor.OPERATOR);
if("new" == op && constructor != null) {
final MethodHandle ctorInvocation = constructor.getInvocation(desc, linkerServices);
if(ctorInvocation != null) {
return new GuardedInvocation(ctorInvocation, getClassGuard(desc.getMethodType()));
}
}
return null;
}
}
static Collection<String> getReadableStaticPropertyNames(Class<?> clazz) {
return linkers.get(clazz).getReadablePropertyNames();
}
static Collection<String> getWritableStaticPropertyNames(Class<?> clazz) {
return linkers.get(clazz).getWritablePropertyNames();
}
static Collection<String> getStaticMethodNames(Class<?> clazz) {
return linkers.get(clazz).getMethodNames();
}
@Override
public GuardedInvocation getGuardedInvocation(LinkRequest request, LinkerServices linkerServices) throws Exception {
final Object receiver = request.getReceiver();
if(receiver instanceof StaticClass) {
return linkers.get(((StaticClass)receiver).getRepresentedClass()).getGuardedInvocation(request,
linkerServices);
}
return null;
}
@Override
public boolean canLinkType(Class<?> type) {
return type == StaticClass.class;
}
/*private*/ static final MethodHandle GET_CLASS;
/*private*/ static final MethodHandle IS_CLASS;
/*private*/ static final MethodHandle ARRAY_CTOR = Lookup.PUBLIC.findStatic(Array.class, "newInstance",
MethodType.methodType(Object.class, Class.class, int.class));
static {
final Lookup lookup = new Lookup(MethodHandles.lookup());
GET_CLASS = lookup.findVirtual(StaticClass.class, "getRepresentedClass", MethodType.methodType(Class.class));
IS_CLASS = lookup.findOwnStatic("isClass", Boolean.TYPE, Class.class, Object.class);
}
@SuppressWarnings("unused")
private static boolean isClass(Class<?> clazz, Object obj) {
return obj instanceof StaticClass && ((StaticClass)obj).getRepresentedClass() == clazz;
}
}