/*
 * Copyright 2011 the original author or authors.
 *
 * 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.gradle.cache;

import java.io.Closeable;
import java.io.File;

/**
 * Represents a directory that can be used for caching.
 *
 * <p>By default, a shared lock is held on this cache by this process, to prevent it being removed or rebuilt by another process
 * while it is in use. You can change this use {@link CacheBuilder#withLockOptions(org.gradle.cache.internal.filelock.LockOptions)}.
 *
 * <p>You can use {@link CacheBuilder#withInitializer(org.gradle.api.Action)} to provide an action to initialize the contents
 * of the cache, for building a read-only cache. An exclusive lock is held by this process while the initializer is running.</p>
 *
 * <p>You can also use {@link #useCache(String, org.gradle.internal.Factory)} to perform some action on the cache while holding an exclusive
 * lock on the cache.
 * </p>
 */
public interface PersistentCache extends PersistentStore, CacheAccess, Closeable {
    /**
     * Returns the base directory for this cache.
     */
    File getBaseDir();

    /**
     * Creates an indexed cache implementation that is contained within this cache. This method may be used at any time.
     *
     * <p>The returned cache may only be used by an action being run from {@link #useCache(String, org.gradle.internal.Factory)}.
     * In this instance, an exclusive lock will be held on the cache.
     *
     * <p>The returned cache may not be used by an action being run from {@link #longRunningOperation(String, org.gradle.internal.Factory)}.
     */
    <K, V> PersistentIndexedCache<K, V> createCache(PersistentIndexedCacheParameters<K, V> parameters);

    /**
     * Closes this cache, blocking until all operations are complete.
     */
    void close();
}
