Detailed introduction to ConcurrentHashMap

This article mainly introduces the relevant information about java using ConcurrentHashMap and counters to implement locks. Friends who need it can refer to java. Using ConcurrentHashMap and counters to implement locks. In some scenarios, we want threads to be queued according to certain business data. , the simple code is as follows: import java.util.ArrayList; import java.util.HashMap; import java.util.List; import java.util.Map; import java.util.concurrent.ConcurrentHashMap; import java.util.concurrent.atomic.AtomicInteger; public class TestServiceImpl {

1. How does java use ConcurrentHashMap and counters to implement locks in detail

Introduction: This article mainly introduces the relevant information about Java using ConcurrentHashMap and counter to implement locks. Friends in need can refer to

##2. Detailed explanation of the sample code of three methods of Java fine-grained lock implementation

##Introduction: Recently at work I encountered some high-concurrency scenarios that required locking to ensure the correctness of the business logic, and it was required that the performance should not be greatly affected after locking. The initial idea is to lock through the timestamp, id and other keywords of the data to ensure the concurrency of different types of data processing. The lock granularity provided by Java's own API is too large to meet these needs at the same time, so I wrote a few simple extensions myself... 1. Segmented locks draw on the segmentation idea of ​​concurrentHashMap, first generate a certain number of locks, When used specifically, the corresponding lock will be returned based on the key. This is the simplest of several implementations..

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Commonly used tool classes in the activeMQ publish-subscribe model

Introduction: package com.jms; import java.util.Map; import java.util.concurrent.ConcurrentHashMap; import javax.jms.BytesMessage; import javax.jms.Connection; import javax.jms.ConnectionFactory; import javax.jms. Destination;import javax.jms.JMSException;impo

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