If Else Java Code

In the previous installment, I introduced the innovative way in which the next generation of Java language was used to eliminate the flashy things and complexities in the Java language. In this installment, I'll show how these languages eliminate some of the flaws in Java: exceptions, statements and expressions, and the edge of the http://www.aliyun.com/zixun/aggregation/19527.html ">null." The expression Java language inherits from the C language ...

This article covers some JVM principles and Java bytecode Directives, recommend interested readers to read a classic book on the JVM, Deep Java Virtual Machine (2nd edition), and compare it with the IL assembly directives I described in ". NET 4.0 object-oriented Programming". Believe that readers will have some inspiration. 　　It is one of the most effective learning methods to compare the similarities and differences of two similar things carefully. In the future, I will also release other articles on personal blog, hoping to help readers of the book broaden their horizons, inspire thinking, we discuss technology together ...

Knowing how the MapReduce program works, the next step is to implement it through code. We need three things: a map function, a reduce function, and some code to run the job. The map function is represented by the Mapper interface implementation, which declares a map () method. 　　Example 2-3 shows our map function implementation. Example 2-3. Find the highest temperature of the mapper import java.io.IOException; &http ...

This article is my second time reading Hadoop 0.20.2 notes, encountered many problems in the reading process, and ultimately through a variety of ways to solve most of the. 　　Hadoop the whole system is well designed, the source code is worth learning distributed students read, will be all notes one by one post, hope to facilitate reading Hadoop source code, less detours. 1 serialization core Technology The objectwritable in 0.20.2 version Hadoop supports the following types of data format serialization: Data type examples say ...

Take the XX data file from the FTP host. 　　Tens not just a concept, represents data that is equal to tens of millions or more than tens of millions of data sharing does not involve distributed collection and storage and so on. Is the processing of data on a machine, if the amount of data is very large, you can consider distributed processing, if I have this experience, will be in time to share. 　　1, the application of the FTP tool, 2, tens the core of the FTP key parts-the list directory to the file, as long as this piece is done, basically the performance is not too big problem. You can pass a ...

While the term cloud computing is not new (Amazon started providing its cloud services in 2006), it has been a real buzzword since 2008, when cloud services from Google and Amazon gained public attention. Google's app engine enables users to build and host Web applications on Google's infrastructure. Together with S3,amazonweb services also includes elastic Cloud Compute (EC2) calculation ...

Editor's note: The last period of time reproduced in the "5 minutes to understand docker! "Very popular, a short 1500 words, let everyone quickly understand the Docker." Today, I saw the author make a new novel, and immediately turned over. The reason to call this code reading as a fantasy trip is because the author Liu Mengxin (@oilbeater) in the process of reading Docker source, found a few interesting things: from the code point of view Docker did not start a new development mechanism, but the existing tested isolation security mechanism to use the full use, Including Cgroups,c ...

Do not do this anymore: public boolean foo () {if (true) {return true;} else {return false;}} Every time I dig into an open source project, I see that it's probably written by some expert I've been amazed at the code reviewed by experienced professionals and no one at all stopped the developer from randomly placing return statements in this method. Please tell me, it is very difficult to write the code below ... public b ...

To use Hadoop, data consolidation is critical and hbase is widely used. In general, you need to transfer data from existing types of databases or data files to HBase for different scenario patterns. The common approach is to use the Put method in the HBase API, to use the HBase Bulk Load tool, and to use a custom mapreduce job. The book "HBase Administration Cookbook" has a detailed description of these three ways, by Imp ...

Nutch Index Source Code Analysis (i) blog Category: Large data processing Research Nutchsolrhadoop index Nutch Integration Slor Index Method Introduction/** * indexing * @param solrurl SOLR web address * @param CRA WLDB Crawl db storage path: \crawl\crawldb ...