Java File Lock Example

This paper is an excerpt from the book "The Authoritative Guide to Hadoop", published by Tsinghua University Press, which is the author of Tom White, the School of Data Science and engineering, East China Normal University. This book begins with the origins of Hadoop, and integrates theory and practice to introduce Hadoop as an ideal tool for high-performance processing of massive datasets. The book consists of 16 chapters, 3 appendices, covering topics including: Haddoop;mapreduce;hadoop Distributed file system; Hadoop I/O, MapReduce application Open ...

Now almost any application, such as a website, a web app and a mobile app, needs a picture display function, which is very important for the picture function from the bottom up. Must have a forward-looking planning picture server, picture upload and download speed is of crucial importance, of course, this is not to say that it is to engage in a very NB architecture, at least with some scalability and stability. Although all kinds of architecture design, I am here to talk about some of my personal ideas. For the picture server IO is undoubtedly the most serious resource consumption, for web applications need to picture service ...

This article is the 3rd and final part of a series of articles on building mixed cloud applications, examining governance and security for cloud computing. This article expands the Hybridcloud application for part 2nd by examining how to add access control policies to the Amazon simple Queue Service (SQS). Learn more about how Hybridcloud applications authenticate themselves to cloud services ...

In the past, we have introduced some principles of software development, such as the 10 commandments of high quality code and the UNIX design principles described in the UNIX legend (next article). I believe that you can learn from middle school some knowledge of design principles, as I said in the "How Do I Recruit procedures", a good programmer usually consists of its operational skills, knowledge level, experience level and ability four aspects. Here I would like to talk about some of the principles of design, I think these things belong to the long-term experience summed up knowledge. These principles should be understood by every programmer. But...

Initially, the platform, the service vendor, establishes its own market differences based on the language it supports, such as Java or. NET, but in the end they continue to evolve to support multiple languages and, ultimately, the infrastructure that serves to support data storage, messaging, application services, and mobility. The market provides a variety of PAAs for developers. Although it seems that PAAs vendors are very similar, but there are many differences. Consider the types that can be controlled, and if so, developers can configure them on the infrastructure. Ideally, PAAs vendors manage all of the implementation ...

Basically are in group discussion, when others ask the introductory questions, later thought of new problems to add in. 　　But the problem of getting started is also very important, the understanding of the principle determines the degree of learning can be in-depth. 　　Hadoop is not discussed in this article, only peripheral software is introduced. 　　Hive: This is the most software I've ever asked, and it's also the highest utilization rate around Hadoop. 　　What the hell is hive? How to strictly define hive is really not too easy, usually for non-Hadoop professionals ...

May 23-May 25, 2012 cloud base of China Cloud Computing Conference opened the curtain, show cloud practice, explore cloud trend, share cloud future. The cloud base shows the latest technologies and new products in the field of cloud computing, and discusses the development trend of cloud computing, the great value of large data, the energy-saving of data center in cloud times and so on. 　　Tian Yun Technology Skyform Research and development team director Zhang Yi introduced days and so friends characteristics and design ideas, and share cases. Zhang Yi: Good afternoon, I divided two parts, the first part of the introduction of the day ...

The cloud computing platform plays a "dream lover" role in the process of serving developers, PAAs also provides the services of cloud computing services and platforms for ordinary developers, while introducing open source technology in PAAs provides a fairly open and advanced technical support for this service platform, including Red Hat, VMware and others play an important role in this field. PAAs and developers who play for developers and PAAs service platforms, there is no one who is completely dependent on the situation, the general understanding is that the user of the tool platform has a certain dominance ...

Intermediary transaction SEO diagnosis Taobao guest Cloud host technology Hall despite 2012 of years of technical keywords also continue to lock in the "cloud", "virtualization, large data, but the return to the enterprise IT architecture issues, we are not difficult to find, these endless new technologies brought to the enterprise, not only upgrade, but also bring some problems: "Because of these changes and challenges, there is a slight change in it construction, and there is a sense of getting out of control." 　　"Pu Yuan Middleware Business Department deputy general manager, product development Department general manager Wang Keqiang pointed out." Runaway Original ...

Previously NoSQL databases were indifferent to new and emerging projects around the world, and we often heard those with ambitious trumpeter patting their chests to ensure that their new nosql applications would break all the old frames and bring new things. In reality, however, it is overblown that NoSQL is still unable to get into Wall Street, even if the trendy developers are only willing to use it for trivial matters in their lives. Because of the limitations of the table structure is too large, if you can discard these, the speed of the database can be improved quality. At this moment, ...