I haven’t written Java code to access relational database for a while. Over the years there have been lots of progresses, especially with various Object Relational Mapping (ORM) frameworks. With these frameworks, accessing relational databases becomes pretty easy. In some cases, you don’t have to know SQL at all. Of course understanding SQL is always an advantage.
One of the most famous framework to support map-reduce for large scale data processing, a.k.a. BigData, is Hadoop as I introduced almost two years ago here. Data processing wise, the Java 8 stream API can do pretty much the same. Here is a quick sample that shows how it count number of words in string. There are significant differences in how they are implemented and the cases in which they should be used. Let’s discuss them after the sample.
Java Collections APIs consists of well designed classes and interfaces for managing all sorts of data structures. With Java 8, there is a new enhancement called Stream API related to the Collection APIs (see What’s New in JDK 8). I spent some time to study the new feature last week as part of my effort to bring myself up to date with Java 8.