CachedPackUriProvider.java

/*
 * Copyright (C) 2019, Google LLC. and others
 *
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Distribution License v. 1.0 which is available at
 * https://www.eclipse.org/org/documents/edl-v10.php.
 *
 * SPDX-License-Identifier: BSD-3-Clause
 */
package org.eclipse.jgit.internal.storage.pack;

import java.io.IOException;
import java.util.Collection;
import org.eclipse.jgit.annotations.Nullable;

/**
 * Provider of URIs corresponding to cached packs. For use with the
 * "packfile-uris" feature.
 * @since 5.5
 */
public interface CachedPackUriProvider {

    /**
     * @param pack the cached pack for which to check if a corresponding URI
     *  exists
     * @param protocolsSupported the protocols that the client has declared
     *  support for; if a URI is returned, it must be of one of these
     *  protocols
     * @throws IOException implementations may throw this
     * @return if a URI corresponds to the cached pack, an object
     *  containing the URI and some other information; null otherwise
     * @since 5.5
     */
    @Nullable
    PackInfo getInfo(CachedPack pack, Collection<String> protocolsSupported)
        throws IOException;

    /**
     * Information about a packfile.
     * @since 5.5
     */
    public static class PackInfo {
        private final String hash;
        private final String uri;

        private final long size;

        /**
         * Constructs an object containing information about a packfile.
         *
         * @param hash
         *            the hash of the packfile as a hexadecimal string
         * @param uri
         *            the URI corresponding to the packfile
         * @param size
         *            the size of the packfile in bytes
         */
        public PackInfo(String hash, String uri, long size) {
            this.hash = hash;
            this.uri = uri;
            this.size = size;
        }

        /**
         * @return the hash of the packfile as a hexadecimal string
         */
        public String getHash() {
            return hash;
        }

        /**
         * @return the URI corresponding to the packfile
         */
        public String getUri() {
            return uri;
        }

        /**
         * @return the size of the packfile in bytes (-1 if unknown)
         */
        public long getSize() {
            return size;
        }
    }
}