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In this paper, try, catch, finally and return are combined by several examples. Example 1: public String finallyTest() { String s = null; try { System.out.println("Enter try block"); s = "try block"; //String .valueOf(null); } catch (Exception e) { // TODO: handle exception System.out.println("Enter c ...

order This paper mainly studies netty buffer watermark s of storm client Config storm-2.0.0/storm-client/src/jvm/org/apache/storm/Config.java /** * Netty based messaging: The netty write buffer high watermark in bytes. * <p> * If the number of bytes queued in the netty's write buffer exceeds this value, the netty {@code ...

Design Patterns The Foundation of Reusable Object-Oriented Software Design pattern is a set of repeated use, most people know, classification and cataloguing, code design experience summary. Design patterns are used to reuse code, make it easier for others to understand, and ensure code reliability. Undoubtedly, design patterns are ...

On Date or Time Stamp Types in Distributed Systems Recently, using Inceptor to query fields of type Date or Timestamp in TDH, we have encountered many problems with unstable or incorrect return values. There are two main problems: Dates of some special Date types are extra hours and seconds, and they are all "01:00:00" Date/Timest ...

Jps, jstat, jstack and jmap are commonly used tools to analyze problems encountered by tomcat when analyzing jvm in operation and maintenance.The common problems of tomcat are:  OOM, lock dead, lock contention, Java consumes too much CPU  The above tools can be used for analysis.Fast Entry of Common Analytical Methods in Production:&n ...

This label is the most important label in my opinion. Firstly, the characteristics of Java Bean are introduced. It can be used on any machine with JVM without recompiling. 1. Write rules for JavaBean s: (1) If the name of the member variable of a class is xxx, two methods can be defined in the class to change or obtain the value of the m ...

Preface Last time, after understanding the basic grammar of cljs and the strange error prompt of clojurescript.net, we must painfully build a local development environment for further study of cljs. Existing build tools Because browsers can only run JS, but can not run cljs directly, we need to build a precompiled environment to compile cljs in ...

Reprinted to https://www.cnblogs.com/hucn/p/3572384.html I encountered the problem of throwing an exception java.lang.OutOfMemoryError when I deployed locally: GC overhead limit exceeded caused the service to fail. Looking at the log, I found that too many resources were loaded into memory, the local performance was not good, and the gc ti ...

Files should be a common data source in development, so FileInputStream and FileOutputStream are important implementation classes in Java IO byte stream. Before I talk about FileInputStream and FileOutputStream, I have to mention File classes. File is also a class in the java.io package. It is mainly used to describe the path of files and fi ...