PostUploadHookChain.java

/*
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 * available at http://www.eclipse.org/org/documents/edl-v10.php
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package org.eclipse.jgit.transport;

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

import org.eclipse.jgit.storage.pack.PackStatistics;

/**
 * {@link org.eclipse.jgit.transport.PostUploadHook} that delegates to a list of
 * other hooks.
 * <p>
 * Hooks are run in the order passed to the constructor.
 *
 * @since 4.1
 */
public class PostUploadHookChain implements PostUploadHook {
    private final List<PostUploadHook> hooks;

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

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

    /** {@inheritDoc} */
    @Override
    public void onPostUpload(PackStatistics stats) {
        for (PostUploadHook hook : hooks) {
            hook.onPostUpload(stats);
        }
    }

    private PostUploadHookChain(List<PostUploadHook> hooks) {
        this.hooks = Collections.unmodifiableList(hooks);
    }
}