PreUploadHookChain.java

/*
 * Copyright (C) 2011, Google Inc. 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.transport;

import java.util.Collection;
import java.util.Collections;
import java.util.List;
import java.util.stream.Collectors;

import org.eclipse.jgit.lib.ObjectId;

/**
 * {@link org.eclipse.jgit.transport.PreUploadHook} that delegates to a list of
 * other hooks.
 * <p>
 * Hooks are run in the order passed to the constructor. If running a method on
 * one hook throws an exception, execution of remaining hook methods is aborted.
 */
public class PreUploadHookChain implements PreUploadHook {
    private final List<PreUploadHook> hooks;

    /**
     * Create a new hook chaining the given hooks together.
     *
     * @param hooks
     *            hooks to execute, in order.
     * @return a new hook chain of the given hooks.
     */
    public static PreUploadHook newChain(List<PreUploadHook> hooks) {
        List<PreUploadHook> newHooks = hooks.stream()
                .filter(hook -> !hook.equals(PreUploadHook.NULL))
                .collect(Collectors.toList());

        if (newHooks.isEmpty()) {
            return PreUploadHook.NULL;
        } else if (newHooks.size() == 1) {
            return newHooks.get(0);
        } else {
            return new PreUploadHookChain(newHooks);
        }
    }

    /** {@inheritDoc} */
    @Override
    public void onBeginNegotiateRound(UploadPack up,
            Collection<? extends ObjectId> wants, int cntOffered)
            throws ServiceMayNotContinueException {
        for (PreUploadHook hook : hooks) {
            hook.onBeginNegotiateRound(up, wants, cntOffered);
        }
    }

    /** {@inheritDoc} */
    @Override
    public void onEndNegotiateRound(UploadPack up,
            Collection<? extends ObjectId> wants, int cntCommon,
            int cntNotFound, boolean ready)
            throws ServiceMayNotContinueException {
        for (PreUploadHook hook : hooks) {
            hook.onEndNegotiateRound(up, wants, cntCommon, cntNotFound, ready);
        }
    }

    /** {@inheritDoc} */
    @Override
    public void onSendPack(UploadPack up,
            Collection<? extends ObjectId> wants,
            Collection<? extends ObjectId> haves)
            throws ServiceMayNotContinueException {
        for (PreUploadHook hook : hooks) {
            hook.onSendPack(up, wants, haves);
        }
    }

    private PreUploadHookChain(List<PreUploadHook> hooks) {
        this.hooks = Collections.unmodifiableList(hooks);
    }
}