FunctionIntrinsics.java

/*
 * Copyright 2010-2015 JetBrains s.r.o.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the 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.
 */

package org.jetbrains.kotlin.js.translate.intrinsic.functions;

import com.google.common.collect.Lists;
import gnu.trove.THashMap;
import org.jetbrains.annotations.NotNull;
import org.jetbrains.annotations.Nullable;
import org.jetbrains.kotlin.descriptors.FunctionDescriptor;
import org.jetbrains.kotlin.js.translate.intrinsic.functions.basic.FunctionIntrinsic;
import org.jetbrains.kotlin.js.translate.intrinsic.functions.factories.*;

import java.util.List;
import java.util.Map;

public final class FunctionIntrinsics {

    @NotNull
    private final Map<FunctionDescriptor, FunctionIntrinsic> intrinsicCache = new THashMap<>();

    @NotNull
    private final List<FunctionIntrinsicFactory> factories = Lists.newArrayList();

    public FunctionIntrinsics() {
        registerFactories();
    }

    private void registerFactories() {
        register(LongOperationFIF.INSTANCE);
        register(PrimitiveUnaryOperationFIF.INSTANCE);
        register(PrimitiveBinaryOperationFIF.INSTANCE);
        register(ArrayFIF.INSTANCE);
        register(TopLevelFIF.INSTANCE);
        register(NumberAndCharConversionFIF.INSTANCE);
        register(ThrowableConstructorIntrinsicFactory.INSTANCE);
        register(ExceptionPropertyIntrinsicFactory.INSTANCE);
    }

    private void register(@NotNull FunctionIntrinsicFactory instance) {
        factories.add(instance);
    }

    @NotNull
    public FunctionIntrinsic getIntrinsic(@NotNull FunctionDescriptor descriptor) {
        FunctionIntrinsic intrinsic = lookUpCache(descriptor);
        if (intrinsic != null) {
            return intrinsic;
        }
        intrinsic = computeAndCacheIntrinsic(descriptor);
        return intrinsic;
    }

    @Nullable
    private FunctionIntrinsic lookUpCache(@NotNull FunctionDescriptor descriptor) {
        return intrinsicCache.get(descriptor);
    }

    @NotNull
    private FunctionIntrinsic computeAndCacheIntrinsic(@NotNull FunctionDescriptor descriptor) {
        FunctionIntrinsic result = computeIntrinsic(descriptor);
        intrinsicCache.put(descriptor, result);
        return result;
    }

    @NotNull
    private FunctionIntrinsic computeIntrinsic(@NotNull FunctionDescriptor descriptor) {
        for (FunctionIntrinsicFactory factory : factories) {
            FunctionIntrinsic intrinsic = factory.getIntrinsic(descriptor);
            if (intrinsic != null) {
                return intrinsic;
            }
        }
        return FunctionIntrinsic.NO_INTRINSIC;
    }
}