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http://120.79.167.88:4444/articles/2019/05/12/1557661499842.html Record the difference between Redis cache and spring cache 1.Redis is a third-party cache, so the cache data still exists after the project is restarted 2. Spring cache is built on the JVM for caching, so the cache will disappear automatically after the project i ...

Spring boot actual e-commerce project mall (20k+star) address: https://github.com/macrozheng/mall abstract Spring Boot Admin can monitor various indicators of spring boot application and can be used as the monitoring center in the microservice architecture. This article will introduce its usage in detail. Introduction to Spring Boot Admin Spri ...

I. overview Sharing mode: "sharing" is the meaning of sharing, which means that one thing is shared by all, and this is the ultimate purpose of the mode. Sharing element mode is similar to singleton mode in that only one object is generated to be shared. There is a problem here, that is, the modification of shared objects. In order to ...

1. Polymorphic grammar 1. If there is no inheritance relationship between two classes, polymorphism cannot be used for compilation. 2. No matter upward or upward transformation, inheritance is needed. 3. When is the downward transformation needed? When the called method or property is specific to a subtype and does not exist in the parent t ...

I. overview Sharing mode: "sharing" is the meaning of sharing, which means that one thing is shared by all, and this is the ultimate purpose of the mode. Sharing element mode is similar to singleton mode in that only one object is generated to be shared. There is a problem here, that is, the modification of shared objects. In order to ...

Class File The File class is in the java.io package. IO stands for input and output, input and output. Represents files and directories that are not platform related. You can create, delete, rename, but you cannot access the file content. Constants in the File class: import java.io.File; public class TestFileConst { public static void mai ...

The concept of abnormality An exception is a mechanism by which a program notifies the caller of an error at run time. The runtime refers to the errors that occur during the process of compiling the class file and executing it by the JVM. There are many kinds of exceptions. Different kinds of excep ...

Concurrent basis Principles of concurrent programming Atomicity Atomicity refers to that in an operation, the cpu can't pause and then schedule in the middle of the process, neither be interrupted by the operation, that is to say, one operation or multiple operations are either all executed and the execution process will not be interrupted b ...

Introduction: Production failure scenario introduction Three handshakes in TCP connection TCP disconnect four wave process Analyzing source code with Java stack Find the "culprit" in the stack Summary of problem optimization scheme 1. Production failure scenario introduction Business profile: This service mainly provides external p ...

1. Thread status and switch There are six states of threads in Java, which are implemented by enumerating classes in Thread. As follows, I explain each state to some extent. 　　public enum State { /** Indicates that a thread is not enabled (that is, the start method is not called)*/ NEW, /** * JVM All ...