<title>Java-based architecture for digital library data storage</title>

Abstract

ABSTRACT The Alexandria Digital Library Project has been tasked with the goal of building a digital geographical library. To meetthese requirements we have designed and prototyped an intelligent Data Store to store its holdings; the library' s map, image,and geographical data are viewed as a collection of distributed objects. Developed using the Java language, the Data Storewas designed to address the problems associated with digital library storage: interoperability, extensibility, distribution, andelimination of server bottlenecks.Keywords: digital library, storage, distributed objects, extensibility, interoperability. 1 INTRODUCTION The Alexandria Digital Library Project at UC Santa Barbara was initiated in 1994 with the goal of building a digitallibrary ofmap and imagery data. The library's geographical images are massive, some taking up to a terabyte of disk space;furthermore, the number of images are voluminous, library holdings easily exceeding 1,000,000 items. With such largeamounts of data, heavy demands are made on its storage and management. To address these requirements, we introduce thedesign of an intelligent Data Store.The Data Store is a storage manager that provides users with a host of services. At the heart of the Data Store is itsdata model. Each item in the Data Store is viewed as an object, belonging to some class. Associated with the class are aset of methods that operate on the object. To take an example, a LANDSAT photograph of Santa Barbara County consistsof an image associated with meta-data; this is treated as an instance of an object stored by the Data Store. The objectbelongs