/*
* This file is part of LanternServer, licensed under the MIT License (MIT).
*
* Copyright (c) LanternPowered <https://www.lanternpowered.org>
* Copyright (c) SpongePowered <https://www.spongepowered.org>
* Copyright (c) contributors
*
* 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 org.lanternpowered.server.event.filter.delegate;
import static org.objectweb.asm.Opcodes.ACONST_NULL;
import static org.objectweb.asm.Opcodes.ALOAD;
import static org.objectweb.asm.Opcodes.ARETURN;
import static org.objectweb.asm.Opcodes.ASTORE;
import static org.objectweb.asm.Opcodes.CHECKCAST;
import static org.objectweb.asm.Opcodes.GETFIELD;
import static org.objectweb.asm.Opcodes.GOTO;
import static org.objectweb.asm.Opcodes.IFNE;
import static org.objectweb.asm.Opcodes.INVOKEINTERFACE;
import static org.objectweb.asm.Opcodes.INVOKEVIRTUAL;
import org.objectweb.asm.ClassWriter;
import org.objectweb.asm.Label;
import org.objectweb.asm.MethodVisitor;
import org.objectweb.asm.Opcodes;
import org.spongepowered.api.event.filter.type.Exclude;
import java.lang.reflect.Method;
public class ExcludeSubtypeFilterDelegate extends SubtypeFilterDelegate {
public ExcludeSubtypeFilterDelegate(Exclude anno) {
super(anno.value());
}
@Override
public int write(String name, ClassWriter cw, MethodVisitor mv, Method method, int locals) {
// TODO could do an optimization here to inline a single instanceof if
// the set would contain only a single member
mv.visitVarInsn(ALOAD, 0);
mv.visitFieldInsn(GETFIELD, name, "classes", "Ljava/util/Set;");
// Loop through the classes set's members
mv.visitMethodInsn(INVOKEINTERFACE, "java/util/Set", "iterator", "()Ljava/util/Iterator;", true);
mv.visitVarInsn(ASTORE, locals);
Label continueLabel = new Label();
mv.visitJumpInsn(GOTO, continueLabel);
Label loopStart = new Label();
mv.visitLabel(loopStart);
mv.visitVarInsn(ALOAD, locals);
mv.visitMethodInsn(INVOKEINTERFACE, "java/util/Iterator", "next", "()Ljava/lang/Object;", true);
mv.visitTypeInsn(CHECKCAST, "java/lang/Class");
mv.visitVarInsn(ALOAD, 1);
mv.visitMethodInsn(INVOKEVIRTUAL, "java/lang/Class", "isInstance", "(Ljava/lang/Object;)Z", false);
mv.visitJumpInsn(Opcodes.IFEQ, continueLabel);
mv.visitInsn(ACONST_NULL);
mv.visitInsn(ARETURN);
mv.visitLabel(continueLabel);
mv.visitVarInsn(ALOAD, locals);
mv.visitMethodInsn(INVOKEINTERFACE, "java/util/Iterator", "hasNext", "()Z", true);
mv.visitJumpInsn(IFNE, loopStart);
return locals + 1;
}
}