001    /*
002     * Copyright 2010-2013 JetBrains s.r.o.
003     *
004     * Licensed under the Apache License, Version 2.0 (the "License");
005     * you may not use this file except in compliance with the License.
006     * You may obtain a copy of the License at
007     *
008     * http://www.apache.org/licenses/LICENSE-2.0
009     *
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS,
012     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013     * See the License for the specific language governing permissions and
014     * limitations under the License.
015     */
016    
017    package org.jetbrains.jet.lang.resolve.lazy.storage;
018    
019    import com.intellij.openapi.util.Computable;
020    import com.intellij.util.Consumer;
021    import com.intellij.util.Function;
022    import org.jetbrains.annotations.NotNull;
023    import org.jetbrains.jet.lang.resolve.BindingTrace;
024    
025    public interface StorageManager {
026        /**
027         * Given a function compute: K -> V create a memoized version of it that computes a value only once for each key
028         * @param compute the function to be memoized
029         * @param valuesReferenceKind how to store the memoized values
030         *
031         * NOTE: if compute() has side-effects the WEAK reference kind is dangerous: the side-effects will be repeated if
032         *       the value gets collected and then re-computed
033         */
034        @NotNull
035        <K, V> MemoizedFunctionToNotNull<K, V> createMemoizedFunction(@NotNull Function<K, V> compute, @NotNull ReferenceKind valuesReferenceKind);
036        @NotNull
037        <K, V> MemoizedFunctionToNullable<K, V> createMemoizedFunctionWithNullableValues(@NotNull Function<K, V> compute, @NotNull ReferenceKind valuesReferenceKind);
038    
039        @NotNull
040        <T> NotNullLazyValue<T> createLazyValue(@NotNull Computable<T> computable);
041    
042        /**
043         * {@code postCompute} is called after the value is computed, but before any other thread sees it (the current thread may
044         * see it in between)
045         */
046        @NotNull
047        <T> NotNullLazyValue<T> createLazyValueWithPostCompute(@NotNull Computable<T> computable, @NotNull Consumer<T> postCompute);
048    
049        @NotNull
050        <T> NullableLazyValue<T> createNullableLazyValue(@NotNull Computable<T> computable);
051    
052        /**
053         * {@code postCompute} is called after the value is computed, but before any other thread sees it (the current thread may
054         * see it in between)
055         */
056        @NotNull
057        <T> NullableLazyValue<T> createNullableLazyValueWithPostCompute(@NotNull Computable<T> computable, @NotNull Consumer<T> postCompute);
058    
059        @NotNull
060        BindingTrace createSafeTrace(@NotNull BindingTrace originalTrace);
061    
062        enum ReferenceKind {
063            STRONG,
064            WEAK
065        }
066    }