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  Those interaction methods we can play with

Smartphones have become one important part of our lives, the phone apps also play more and more important roles. They can help us live through the boring time or help us connect to our close friends fat away from us or help us get information,etc. There are also some interesting interaction methods since the birth of smartphones. We can play with them while we interact with the smartphones. Here we summarize some of them. 1. Shake Since WeChat introduces the Shake method to find people which yo...

   Interaction,Mobile device,Google glass     2013-05-07 05:21:15

  Translating math into code with examples in Java, Racket, Haskell and Python

Discrete mathematical structures form the foundation of computer science.These structures are so universal that most research papers in the theory of computation, programming languages and formal methods present concepts in terms of discrete mathematics rather than code.The underlying assumption is that the reader will know how to translate these structures into a faithful implementation as a working program.A lack of material explaining this translation frustrates outsiders.What deepens that fr...

   Math,Algorithms,Formula,Program,Python     2011-11-14 08:43:15

  The concept of Iterative Model in a Software Development Life Cycle (SDLC)

The iterative model implemented in any Software Development Life Cycle is all about an initial, simplified implementation which may or may not gain more complexity in future. Furthermore, it is can even be called as a broader feature set until and unless the final system is accomplished. Now while discussing the model, chances are there that he concept of incremental development will also often be used liberally and interchangeably. This means incremental alterations made during the design and i...

   SOFTWARE DEVELOPMENT,SDLC,ITERATIVE MODEL,SOFTWARE DEVELOPMENT LIFE CYCLE     2017-09-11 06:02:39

  Using MemoryMappedBuffer to handle large file in Java

When handling large files, it will largely affect the process speed while using traditional FileInputStream, FileOutputStream or RandomAccessFile since they trigger lots of read and write operations. In Java NIO, a new way of handling large file is introduced which is to use MmeoryMappedBuffer to create memory mapped file. Memory-mapped I/O uses the filesystem to establish a virtual memory mapping from user space directly to the applicable filesystem pages. With a memory-mapped file, you can pre...

   JAVA,IO,NIO     2015-11-13 01:58:08

  Is Scala Only for Computer Scientists?

I have experience struggling through these kinds of things andI know enough about the subject that I can understand why they did it that way. But my concern is that this should be an example that a beginner could understand, and they can't. There's too much depth exposed. Here's the example, which is written as a script: import scala.io.Source._ case class Registrant(line: String) { val data = line.split(",") val first = data(0) val last = data(1) val email = data(2) val payment = da...

   Scala,Application field,Computer science     2012-02-17 07:46:40

  Cleansing data with Pig and storing JSON format to HBase with Pig UDF

Introduction This post will explain you the way to clean data and store JSON format to HBase. Hadoop architect experts also explain Apache Pig and its advantages in Hadoop in this post. Read more and find out how they do it. This post contains steps to do some basic clean the duplication data and convert the data to JSON format to store to HBase. Actually, we have some built-in lib to parse JSON in Pig but it is important to manipulate the JSON data in Java code before store to HBase. Apache Pig...

   JSON,HADOOP ARCHITECT,APACHE HBASE,PIG UDF     2016-06-10 01:13:41

  When will resizing be triggered in Java HashMap?

HashMap is one of the most frequently used collection types in Java, it stores key-value pairs. Ideally it expects to use hash table which expects the data access time complexity to be O(1), however, due to hash conflicts, in reality, it uses linked list or red-black tree to store data which makes the worst case time complexity to be O(logn).  Although collections are using data structures like arrays and linked lists, unlike arrays, they will dynamically resize when there is not enough spa...

   JAVA,RESIZE,HASHMAP,THRESHOLD     2020-05-02 20:41:19

  Java is not the new COBOL

If you Google “Java is the new COBOL” you’ll find a glut of articles proliferating this mantra. I don’t know its origins, however I’m inclined to think it’s mostly repeated (and believed) by the Ruby community. Ruby, from a developer’s perspective is a low-friction language. A developer can just sit down at a text editor and start banging out code without really thinking about such superflous things as types. Java on the other hand, well, you h...

   Java,Ruby,Type,COBOL,Comparison     2011-11-10 10:40:56

  A Month With Scala

Although I’ve played around with Scala for the few months, these efforts largely involved simple scripts and casual reading. It wasn’t until last month that the opportunity to use Scala in a large scale project finally arose and I dove right in. The project was a typical REST based web service built on top of Amazon’s Elastic Beanstalk, SimpleDB, S3 and Redis*. First off let’s talk about why I chose Scala in the first place. After spending a good deal of my las...

   Scala,Functional,OOP,Java,Iteration     2011-12-10 06:03:23

  Java Sequential IO Performance

Many applications record a series of events to file-based storage for later use.  This can be anything from logging and auditing, through to keeping a transaction redo log in an event sourced design or its close relative CQRS.  Java has a number of means by which a file can be sequentially written to, or read back again.  This article explores some of these mechanisms to understand their performance characteristics.  For the scope of this article I will be using pre-a...

   Java,IO,Sequential,Blocking     2012-02-23 07:09:10