Singleton in Java – the proper way « The guy who does not speak… Update after some comments: this post is not a discussion whether to use Singleton or not. It’s not a discussion on why Singleton might be an anti-pattern. It’s just an example on an alternative implementation of Singleton in Java. Just that. There are two classic ways to implement Singleton pattern in Java: public final instance field or static factory method to create/get instance. AllegroGraph RDFStore Web 3.0's Database Geospatial and Temporal Reasoning AllegroGraph stores geospatial and temporal data types as native data structures. Combined with its indexing and range query mechanisms, AllegroGraph lets you perform geospatial and temporal reasoning efficiently. Social Networking Analysis AllegroGraph includes an SNA library that treats a triple-store as a graph of relations, with functions for measuring importance and centrality as well as several families of search functions. Example algorithms are nodal-degree, nodal-neighbors, ego-group, graph-density, actor-degree-centrality, group-degree-centrality, actor-closeness-centrality, group-closeness-centrality, actor betweenness-centrality, group-betweenness-centrality, page-rank-centrality, and cliques. Geospatial and temporal primitives combined with SNA functions form an Activity Recognition framework for flexibly analyzing networks and events in large volumes of structured and unstructured data.
e AcornDB AcornDB is a high performance, small footprint, transactional object oriented database written entirely in Java. It stores data in the application's native format, so no runtime data translation is required. AcornDB supports full ACID transactions and recovery. Jeremy Zawodny's blog I found myself reading NoSQL is a Premature Optimization a few minutes ago and threw up in my mouth a little. That article is so far off base that I’m not even sure where to start, so I guess I’ll go in order. In fact, I would argue that starting with NoSQL because you think you might someday have enough traffic and scale to warrant it is a premature optimization, and as such, should be avoided by smaller and even medium sized organizations.
AllegroGraph News August 2011 AllegroGraph News November, 2013 In this issue Free Webcast: Augmenting Hadoop for Graph Analytics Wednesday, November 20 - 10:00 AM Pacific E-commerce sites, auction sites, financial institutions, insurance companies and telephone companies all have event based data that describes transactions between customers (Social Networks) that are located in time and space (GeoTemporal). All these transactions together form interesting social graphs and patterns of customer behavior. An Introduction to Domain Driven Design Click here to view the complete list of archived articles This article was originally published in the Winter 2009 issue of Methods & Tools An Introduction to Domain Driven Design Dan Haywood, Haywood Associates Ltd, Today’s enterprise applications are undoubtedly sophisticated and rely on some specialized technologies (persistence, AJAX, web services and so on) to do what they do.
Graph Databases, NOSQL and Neo4j Introduction Of the many different datamodels, the relational model has been dominating since the 80s, with implementations like Oracle, MySQL and MSSQL - also known as Relational Database Management System (RDBMS). Lately, however, in an increasing number of cases the use of relational databases leads to problems both because of Deficits and problems in the modeling of data and constraints of horizontal scalability over several servers and big amounts of data. There are two trends that bringing these problems to the attention of the international software community:
Object2RecordJavaBinding - orient - Object to Record mapping - NoSQL document database light, portable and fast. Supports ACID Tx, Indexes, asynch queries, SQL layer, clustering, etc The ObjectDatabase implementation makes things easier for the Java developer since the binding between Objects to Records is transparent. How it works? OrientDB uses Java reflection and Javassist Proxy to bound POJOs to Records directly. Those proxied instances take care about the synchronization between the POJO and the underlying record. Every time you invoke a setter method against the POJO, the value is early bound into the record. Every time you call a getter method the value is retrieved from the record if the POJO's field value is null.