Programming Applications and Frameworks

Data Persistence The Role of Data in Information Systems Indicating The Need For Data Persistence Understanding the meaning of persistence is important for evaluating different data store systems. Persistence is the continuance of an effect after its cause is removed. In the context of storing data in a computer system, this means that the data survives after the process with which it was created has ended. In other words, for a data store to be considered persistent, it must write to nonvolatile storage. .If you need persistence in your data store, then you need to also understand the four main design approaches that a data store can take and how (or if) these designs provide persistence: 1. Pure in memory , no persistence at all such as memcached or scalaris  2. In memory with periodic snapshots such as Oracle Coherence or Redis  3. Disk based with update in placewrites such as MySQL ISAM or MongoDB In-memory approaches can achieve blazing s...

RESTful Web services Message-oriented middleware (MOM) lets a service's consumers physically and temporally decouple from the service providers. Communication between service providers and their consumers is asynchronous, and they don't need to be available at the same time because they communicate by sending and receiving messages from designated message queues. In contrast, RPC is a synchronous method of requesting remote service execution. Consumers must suspend service execution until they receive a reply from the provider. MOM and RPC have advantages and disadvantages. MOM solutions tend to be more robust to failures than RPC, and they allow service requesters to continue to process while service providers work on their requests. However, programming MOM-based applications is more cumbersome because distribution isn't as transparent to the programmer as with RPCs. In this column, I provide a quantitative framework you can use to compare MOM- and RPC...

Web services and SOAP   Web Applications   Applications that are accessed through browsers are web applications and it is the collection of multiple web pages. These are basically dependent on client server architecture where browser acts as a client which sends the request to server. Afterwards, web pages are rendered as per responses from the server. Purpose of web services is communications between various programs and applications.  During building any web application, order of focus is on: UI portion[Front end implementation] Functional portion[Back end implementation] Web services  Web services are mainly used to communicate the information between two systems ignoring UI interaction. Messages are transferred from one application to another application via JSONS and XMLs etc.  Web services are mainly dependent on back end implementation, UI doesn't have any space. Clients can access only exposed methods of any funct...