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diff --git a/src/mongo/db/catalog/uuid_catalog.h b/src/mongo/db/catalog/uuid_catalog.h
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+++ b/src/mongo/db/catalog/uuid_catalog.h
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+/**
+ *    Copyright (C) 2017 MongoDB Inc.
+ *
+ *    This program is free software: you can redistribute it and/or  modify
+ *    it under the terms of the GNU Affero General Public License, version 3,
+ *    as published by the Free Software Foundation.
+ *
+ *    This program is distributed in the hope that it will be useful,
+ *    but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *    GNU Affero General Public License for more details.
+ *
+ *    You should have received a copy of the GNU Affero General Public License
+ *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ *    As a special exception, the copyright holders give permission to link the
+ *    code of portions of this program with the OpenSSL library under certain
+ *    conditions as described in each individual source file and distribute
+ *    linked combinations including the program with the OpenSSL library. You
+ *    must comply with the GNU Affero General Public License in all respects for
+ *    all of the code used other than as permitted herein. If you modify file(s)
+ *    with this exception, you may extend this exception to your version of the
+ *    file(s), but you are not obligated to do so. If you do not wish to do so,
+ *    delete this exception statement from your version. If you delete this
+ *    exception statement from all source files in the program, then also delete
+ *    it in the license file.
+ */
+
+#pragma once
+
+#include <unordered_map>
+
+#include "mongo/base/disallow_copying.h"
+#include "mongo/db/catalog/collection.h"
+#include "mongo/db/service_context.h"
+#include "mongo/util/uuid.h"
+
+namespace mongo {
+
+/**
+ * This class comprises a UUID to collection catalog, allowing for efficient
+ * collection lookup by UUID.
+ */
+using CollectionUUID = UUID;
+class Database;
+
+class UUIDCatalog {
+    MONGO_DISALLOW_COPYING(UUIDCatalog);
+
+public:
+    static UUIDCatalog& get(ServiceContext* svcCtx);
+    static UUIDCatalog& get(OperationContext* opCtx);
+    UUIDCatalog() = default;
+
+    /**
+     * This function inserts the entry for uuid, coll into the UUID Collection. It is called by
+     * the op observer when a collection is created.
+     */
+    void onCreateCollection(OperationContext* opCtx, Collection* coll, CollectionUUID uuid);
+
+    /**
+     * This function removes the entry for uuid from the UUID catalog. It is called by the op
+     * observer when a collection is dropped.
+     */
+    void onDropCollection(OperationContext* opCtx, CollectionUUID uuid);
+
+    /**
+     * Combination of onDropCollection and onCreateCollection.
+     */
+    void onRenameCollection(OperationContext* opCtx, Collection* newColl, CollectionUUID uuid);
+
+    /**
+     * Implies onDropCollection for all collections in db, but is not transactional.
+     */
+    void onCloseDatabase(Database* db);
+
+    /* This function gets the Collection* pointer that corresponds to
+     * CollectionUUID uuid. The required locks should be obtained prior
+     * to calling this function, or else the found Collection pointer
+     * might no longer be valid when the call returns.
+     */
+    Collection* lookupCollectionByUUID(CollectionUUID uuid) const;
+
+    /* This function gets the NamespaceString from the Collection* pointer that
+     * corresponds to CollectionUUID uuid. If there is no such pointer, an empty
+     * NamespaceString is returned.
+     */
+    NamespaceString lookupNSSByUUID(CollectionUUID uuid) const;
+
+private:
+    mutable mongo::stdx::mutex _catalogLock;
+    mongo::stdx::unordered_map<CollectionUUID, Collection*, CollectionUUID::Hash> _catalog;
+
+    void _registerUUIDCatalogEntry(CollectionUUID uuid, Collection* coll);
+    Collection* _removeUUIDCatalogEntry(CollectionUUID uuid);
+};
+
+}  // namespace mongo