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catalogue Fundamentals: distributed locks Why do I need distributed locks? Characteristics of distributed locks Common scenarios Redis implements distributed locks Redisson distributed lock entry practice reference Fundamentals: distributed locks The synchronized keyword and ReentrantLock reentrant lock in Java can control concurrent ...

Basic introduction Compared with synchronized, it has the following characteristics InterruptibleCan be set to fair lockYou can set the timeoutMultiple condition variables are supported, that is, threads that do not meet the conditions can be placed in different collections to wait Like synchronized, reentrant is supported Basic grammar ...

introduction When I first learned Java reflection mechanism, I just felt very magical, but I didn't know how to use it, so I forgot it after a period of time; Recently, I came into contact with the framework, encountered reflection in my study, and deeply realized the magic of the reflection mechanism. I came back to review the reflection mech ...

Multithreading Using threads, you can put tasks in programs that occupy a long time in the background.The user interface can be more attractive. For example, if the user clicks a button to trigger the processing of some events, a progress bar can pop up to display the processing progress.The program will run faster.In the implementation of som ...

Tip: After the article is written, the catalog can be generated automatically, how to generate the help document to the right Article Directory PrefaceI. Database Operation StatementPreparedStatementResultSetResultSetMetaData2. Return a record in a table for different table query operationsthree And implement common query operatio ...

1, Serialization and deserialization of objects 1. Object serialization stream Introduction to object serialization Object serialization: saving objects to disk or transferring objects over the networkThis mechanism uses a byte sequence to represent an object, which contains information such as object type, object data and attribute ...

   after JDK 1.5, the Java language provides support for annotations, which, like ordinary java code, play a role during runtime. JSR-269: Pluggable Annotations Processing API of JSR-269 specification is implemented in JDK 1.6. Provides a set of standard APIs for plug-in Annotation processors that process annotations during compilatio ...

11. Thread pool (key) Thread pool: 3 methods, 7 parameters and 4 rejection strategies Pool technology The operation of the program, essence: occupy the resources of the system! (optimize the use of resources = > pooling Technology) Create and destroy thread pool, connection pool, memory pool and object pool. It is a waste of resource ...

Source download The source code of this chapter is github What is the lifecycle of spring beans For ordinary Java objects, create the object when new, and then the object can be used. Once the object is no longer used, Java automatically garbage collects it. The objects in Spring are beans. Beans are no different from ordinary Java object ...

1: Basic knowledge points of exceptions (1) What is the exception?      1. Anomalies simulate "abnormal" events in the real world.      2.java uses "classes" to simulate exceptions.      3. Class can create objects.          NullpointerException e = 0*12345； e is the refer ...