| /* |
| * Copyright (C) 2010, 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.lib; |
| |
| import java.io.IOException; |
| |
| import org.eclipse.jgit.errors.MissingObjectException; |
| |
| /** |
| * Queue to open objects asynchronously. |
| * |
| * A queue may perform background decompression of objects and supply them |
| * (possibly out-of-order) to the application. |
| * |
| * @param <T> |
| * type of identifier supplied to the call that made the queue. |
| */ |
| public interface AsyncObjectLoaderQueue<T extends ObjectId> extends |
| AsyncOperation { |
| |
| /** |
| * Position this queue onto the next available result. |
| * |
| * Even if this method returns true, {@link #open()} may still throw |
| * {@link org.eclipse.jgit.errors.MissingObjectException} if the underlying |
| * object database was concurrently modified and the current object is no |
| * longer available. |
| * |
| * @return true if there is a result available; false if the queue has |
| * finished its input iteration. |
| * @throws org.eclipse.jgit.errors.MissingObjectException |
| * the object does not exist. If the implementation is retaining |
| * the application's objects {@link #getCurrent()} will be the |
| * current object that is missing. There may be more results |
| * still available, so the caller should continue invoking next |
| * to examine another result. |
| * @throws java.io.IOException |
| * the object store cannot be accessed. |
| */ |
| boolean next() throws MissingObjectException, IOException; |
| |
| /** |
| * Get the current object, null if the implementation lost track. |
| * |
| * @return the current object, null if the implementation lost track. |
| * Implementations may for performance reasons discard the caller's |
| * ObjectId and provider their own through {@link #getObjectId()}. |
| */ |
| T getCurrent(); |
| |
| /** |
| * Get the ObjectId of the current object. Never null. |
| * |
| * @return the ObjectId of the current object. Never null. |
| */ |
| ObjectId getObjectId(); |
| |
| /** |
| * Obtain a loader to read the object. |
| * |
| * This method can only be invoked once per result |
| * |
| * Due to race conditions with a concurrent modification of the underlying |
| * object database, an object may be unavailable when this method is |
| * invoked, even though next returned successfully. |
| * |
| * @return the ObjectLoader to read this object. Never null. |
| * @throws MissingObjectException |
| * the object does not exist. If the implementation is retaining |
| * the application's objects {@link #getCurrent()} will be the |
| * current object that is missing. There may be more results |
| * still available, so the caller should continue invoking next |
| * to examine another result. |
| * @throws java.io.IOException |
| * the object store cannot be accessed. |
| */ |
| ObjectLoader open() throws IOException; |
| } |