Collectables Database is a simple, easy-to-use application for using the control and data management capabilities of Postgres to catalog various kinds of collections. It delivers content in a format that is easy to use and manipulate within the convenience of a modern Web browser. The initial focus of the application is on cataloging a comic book collection. Collectables Database can run from a hosted Web server or on the user's local machine through the use of a virtual appliance.
Immutable Collections for Java is a library providing immutable/persistent collection classes for Java. While collections are immutable, they provide methods for adding and removing values by creating new modified copies of themselves. Each copy shares almost all of its structure with other copies, to minimize memory consumption. The library includes a singly-linked (cons/cddr style) list/stack, an integer tree-based indexed list, a 2-3 tree-based random access indexed list, a 2-3 tree-based map, a hash tree-based map, and hash- and tree-based sets. All collections provide immutable Cursor as well as standard Iterator classes for looping through all elements. A utility class provides functional style algorithmic processing of Cursors, including foldLeft, foldRight, collect, select, and reject. The 2-3 tree and integer tree classes are optimized for performance and can be used alongside java.util Collections when immutability is needed for safe data sharing.