Video learning notes of "basic data types in binary and Java" on muke.com

Video address: https://www.imooc.com/video/21195 Introduction: as we all know, computers are stored in binary. Learning binary well can help us understand how to deal with data and how to store data types in Java. This course will start from the history of binary system to explain binary related knowledge, such as digit value system countin ...

Posted on Sun, 24 May 2020 05:46:35 -0400 by hmiller73

New features of JDK9: How does the xlog of JVM work correctly?Case Details

JVM is the basis of running java programs. Events in JVM such as GC, class loading, JPMS, heap, threads and so on can actually be logged.Through these logs, we can monitor events in the JVM and, in turn, tune java applications. The Xlog log log service introduced in JDK9 was created for this purpose.Also note: Many people will inevitably enco ...

Posted on Sat, 23 May 2020 02:19:53 -0400 by kpmonroe

From 0 to 1! Dynamic and static agent

trace back to To learn a technology, we need to know why it comes into being, so that we can have the goal and motivation to learn and understand it better First of all, why should there be an agent? There is A common requirement: how to add and enhance some functions when calling methods of class A without modifying class A code? Without co ...

Posted on Thu, 21 May 2020 11:59:19 -0400 by Dollar

Are objects in Java allocated on the heap?

By LittleMagichttps://www.jianshu.com/p/8377e09971b8 In order to prevent ambiguity, we can put it another way: Are Java object instances and array elements allocated memory on the heap? A: not necessarily. When certain conditions are met, they can allocate memory on the (virtual machine) stack. JVM memory structure is very important, review ...

Posted on Wed, 20 May 2020 03:48:52 -0400 by xphoenixx

Fault tolerance of String to null object in Java!

Author: Xiao Hansong blog.xiaohansong.com/2016/03/13/null-in-java-string/ Recently, I was reading Thinking in Java, and I saw this passage: _Primitives that are fields in a class are automatically initialized to zero, as noted in the Everything Is an Object chapter. _ _But the object references are initialized to null, and if you try to call ...

Posted on Wed, 20 May 2020 00:41:26 -0400 by r2ks

Threads for learning notes

Multithreaded 1. Implement multithreading process Is a running program Is the system's independent unit for resource allocation and invocation Each process has its own memory space and system resources thread Is a single sequential control flow in a process and is an execution path Single-threaded: A process with only one execution path is c ...

Posted on Mon, 18 May 2020 12:46:16 -0400 by matt_4013

5-commands commonly used by JVM

Commands commonly used by JVM jps: basic tools View the JAVA process PID. The jps command is used to view all Java processes. Each line is a java process information. jps only looks up the Java processes of the current user, not all processes in the current system. To display other users, it can only use the ps command. jps common parameters ...

Posted on Mon, 18 May 2020 05:01:09 -0400 by Kingy

The first mock exam mode

1, The concept of singleton pattern The so-called single instance is that the whole program has only one instance. This class is responsible for creating its own objects, while ensuring that only one object is created. 2, When to use singleton mode Singleton pattern is one of the most used patterns in design pattern. You can use singl ...

Posted on Fri, 15 May 2020 11:23:10 -0400 by tomdelonge

My jdk source code: String is a special and powerful class!

1, Overview String class is a special existence in java. Although it is not a basic type, it is frequently used. This is mainly because the value of the string object is a constant. We can see why it is a constant in the source code below. Because of this feature, it is thread safe. Next, let's analyze the source code in depth and uncover the ...

Posted on Wed, 13 May 2020 15:20:55 -0400 by arion279

java upload pictures to the storage space of qiniu cloud

If necessary, you can join our Q group [30874228] to discuss technology and provide technical support. We will update articles for you from time to time. Please look forward to it. Code without saying more: In the front end, if I am a plug-in of the layui, I need to import two files for the style: A css style file, a js file <script src="${c ...

Posted on Tue, 12 May 2020 10:19:01 -0400 by Kurtismonger