Since Java 1.4, the JDK has supported NIO(NEW IO). NIO(OS Nonblocking) allows application servers to greatly optimize the threading model. Compared to the traditional blocking IO thread and link to link mode, NIO requires only a small number of threads to process all links. This is a great boon for Java developers, who can develop more efficient web applications based on NIO.
However, using the JDK native API to develop NIO, the programming model is very complex, developers need to understand the Selector, Channel, ByteBuffer three components, in addition to the JDK native NIO implementation there are some stability problems. Netty encapsulates the three component interaction codes inside the framework, which effectively simplifies the programming model so that users can develop NIO network applications more efficiently and ensure the stability of the system.
However, with the new problems, for developers, the framework is easy to use, shielding the underlying details, in return for a lack of in-depth understanding of the principle, performance tuning and theory of the weak, many excellent online products dubbo, Spark, ZooKeeper, elasticSearch, etc., With the use of Netty as the support for the underlying communication IO framework, the underlying principles of Netty are becoming more and more urgent, especially in the interview process.
Today, we sorted out the summary: 2020 Internet factory first line of the latest interview real questions and 2000 common Java job interview questions information (with complete answers).
There are mainly: Alibaba, Tencent, Letxin, China Ping An, Fengchao Technology, OpPO and other big factory real questions, as well as JVM, SPringBoot, SpringCloud, database, Linux, cache, message middleware, source code and other related interview questions.
