Programmer Think

hello everyone! I am an old ape. I love technology. I have been in the Java industry for 7 years and am on the way to learn and share every day! thread 1. Introduction As we all know, multithreading brings us better resource utilization and better program response, so I won't elaborate on its introduction. You can search by yourself. I'm ma ...

OOM memory OOM: out of memory For the memory related configuration of the JVM, there are corresponding recommendations on many open source JAVA components eg:http://rocketmq.apache.org/docs/system-config/ 1. There are not too many JVMs on the memory allocation line > jvm 70% of heap memory%Total machine memory (empirical value) > ...

Before reading this article, you need to understand how to define enumeration and its simple use enumeration 1, How the JVM handles enumerations A simple enumeration class public enum Fruit{ APPLE(67),ORANGE(68),BANANA(69); int code; Fruit(int code){ this.code=code; } } Decompile fruit. Using the Jad command C ...

I Lock interface Lock interface is the foundation of everything. Its abstract class is a tool used to control the access of multiple threads to shared resources The following methods are provided to abstract the whole business: void lock()void lockInterruptibly() throws InterruptedException: breaks the lockboolean tryLock(): non blockin ...

Garbage collector and memory allocation strategy Garbage collector and garbage collection algorithm preface I interviewed interns in April because I saw the JVM garbage collector and recycling algorithm in advance and answered this question. Ha ha, the interviewer directly told me that I could prepare three aspects. Today I want to ...

3. Local Method Stack The local method stack is java The virtual machine needs to provide memory space for some local methods when they are called, which refers to those that are not java How to write code, because Ours java Code has some limitations, it sometimes can't deal directly with the bottom level of our operating system, so it need ...

10. String constant pool (String Table) Basic characteristics of String String: a string, represented by a pair of "". String s1 = "hguo"; // Definition of literal quantity String s2 = new String("hello"); The String class is declared as final and cannot be inherited. The Serializable String interface supports String serialization. ...

I'm Chen PI. I'm an ITer of Internet Coding. I search "Chen Pi's JavaLib" on wechat. I can read the latest article at the first time and reply to [data], so I can get my carefully sorted technical data, e-books, interview data of front-line large factories and excellent resume template. background If you want to do some extra pr ...

1, Why are there four kinds of references 01 At the beginning, when an object is not referenced (that is, there is no attribute / variable reference, for example, Object ob=new Object();ob=null;) It will be automatically recycled by the JVM. It is a strong reference before it is equal to null. For example, if you go to a restaurant for dinner ...

arthas online troubleshooting tool https://github.com/alibaba/arthas/blob/master/README_CN.md step Run our java program Start the jar file of arthas. We can see that the process number of the java program just running is 1, so type in the process number 1 and press enter. It will hang itself to this process Then you can use some command ...