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Some recent knowledge is shared ~ as follows: Stack area usually stores: local variables, parameters, and static space.The space requested by malloc, free, calloc and realloc is usually placed in the heap.Static declarations are usually placed in static storage. The following describes several dynamic memory functions: 1.malloc function and f ...

Semaphore: Semaphore is an abstract data type managed by the operating system, which is used to synchronize the use of shared resources in multiple threads. In essence, a semaphore is an internal data used to indicate how many concurrent reads can be made to the current shared resource. In threading module Semaphore class The semaphore object ...

1: What is generics? (1) Why use generics? For example, the implementation in MyArray class can only save int type data, and other types of data, such as double, String or custom type objects, cannot be stored at all. All use generics. (2) Definition: generics can write type independent code, that is, the written code can be reused by many ...

3.6.5 build string When String is used to continuously splice strings with circular statements, because String is an immutable class, new objects are generated every time, which is inefficient; Therefore, Java provides StringBuilder and StringBuffer to solve this problem. public class Main { public static void main(String[] args){ ...

Characteristics of Map interface implementation class [very practical] Note: This is about the Map interface features of JDK8 Map and Collection exist side by side. Used to save data with mapping relationship: Key - Value (double column element)The key and value in the Map can be data of any reference type and will be encapsulated in the ...

1, Multithreading 1. Simple understanding of multithreading It refers to the technology that multiple threads execute concurrently from software or hardware. Computers with multithreading capability can execute multiple threads at the same time due to hardware support, so as to improve performance. 2. Concurrency and parallelism Par ...

gossip Hahaha, I've been reading computer network books recently. I'm a little lazy when updating my blog. Continue today Basic points 1. IOC essence Inversion of Control (IoC) is a design principle in object-oriented programming, which can be used to reduce the coupling between computer codes.Control inversion is a way to produce or obtain ...

Student achievement management system 1, Design task analysis The main purpose of this topic is to manage students' grades. You can enter scores, query scores, delete score records, and rank scores. Facilitate the unified processing of students' scores after the examination. 2, Design of the overall scheme of student achievement management s ...

JUC Foundation 1. Tube side: monitor, monitor, lock It ensures that only one process is active in the pipe at the same time, that is, the operations defined in the pipe are called by only one process at the same time (implemented by the compiler) However, this does not guarantee that the processes are executed in the designed order Synchroni ...

1. Three problems of concurrent programming 1. Visibility issues Visibility concept Visibility: when one thread modifies a shared variable, the other gets the latest modified value immediately. In practical applications, we need to ensure visibility, but there is no visibility between threads without special methods. It often happens that a ...