Java Concurrency (1)

àì夳堔傛蜴生んèń 2022-03-31 02:46 124阅读 0赞

# Memory that can be shared betweenthreads is called shared memory or heap memory. The term variable as used inthis technical report refers to both fields and array elements. Variables thatare shared between threads are referred to as shared variables. All instance fields,static fields, and array elements are shared variables allocated in heapmemory. Local variables, formal method parameters, and exception-handlerparameters are never shared between threads and are not affected by the memorymodel. #

# The visibility of writes toshared variables can be problematic because the value of a shared variable maybe cached and not written to main memory immediately. Consequently, anotherthread may read a stale value of the variable. #

# A further concern is thatconcurrent executions of code are typically interleaved, and statements may bereordered b the compiler or runtime system to optimize performance. Thisresults in execution orders that are not immediately obvious when the sourcecode is examined. Failure to account for possible reordering is a common sourceof data races. #

# Volatile accesses do notguarantee the atomicity of composite operations such incrementing a variable.Consequently, volatile is not applicable in cases where the atomicity ofcomposite operations must be guaranteed. #

# A correctly synchronized programis one whose sequentially consistent executions do not have any data races.  #

# Correct visibility guaranteesthat multiple threads accessing shared data can view each others’ results, butdoes not establish the order of when each thread reads or writes the data.Correct synchronization guarantees that threads access data in a proper order. #

发表评论取消回复

表情：

评论列表（有 0 条评论，124人围观）

还没有评论，来说两句吧...

相关阅读

相关 java.util.concurrent.atomic

java.util.concurrent.atomic是Java中的一个包，提供了一组原子操作类，用于在多线程环境下进行原子性操作。这些类可用于实现线程安全的、无锁的操作，保证

淩亂°似流年/ 2024年03月17日 10:17/ 0 赞/ 5 阅读

相关 java concurrent并发详解

我们都知道，在JDK1.5之前，Java中要进行业务并发时，通常需要有程序员独立完成代码实现，当然也有一些开源的框架提供了这些功能，但是这些依然没有JDK自带的功能使用起来方便

野性酷女/ 2022年08月03日 05:11/ 0 赞/ 149 阅读

相关 java.util.concurrent 概览

<table style="width:603px; border-left:1px solid rgb(238,238,238); border-right:1px s

骑猪看日落/ 2022年07月15日 11:53/ 0 赞/ 171 阅读

相关 java.util.concurrent 之TimeUnit

TimeUnit 表示给定单元粒度的时间段，它提供在这些单元中进行跨单元转换和执行计时及延迟操作的实用工具方法。TimeUnit 不维护时间信息，但是有助于组织和使用可能跨各种

雨点打透心脏的1/2处/ 2022年06月12日 00:06/ 0 赞/ 146 阅读

相关 java.util.concurrent.Callable

1. java.util.concurrent.Callable 1.1 概述 Callable是一个返回一个结果或者抛出一个异常的任务接口，其中定义了一个call

约定不等于承诺〃/ 2022年06月06日 11:59/ 0 赞/ 130 阅读

相关 java.util.concurrent.CyclicBarrier

java.util.concurrent.CyclicBarrier 概述 CyclicBarrier可以看作是一个栅栏队列。即一组相互联系的并行的任务在进入下一个

Dear 丶/ 2022年06月06日 10:53/ 0 赞/ 145 阅读

相关 java.util.concurrent.CountDownLatch

java.util.concurrent.CountDownLatch 概述 CountDownLatch被用来同步一个或多个任务，强制它们等待由其它任务执行的一组

古城微笑少年丶/ 2022年06月06日 10:13/ 0 赞/ 143 阅读

相关 Java 并发工具包 java.util.concurrent

\ 一、[java并发指南][java] ![这里写图片描述][70] ![这里写图片描述][70 1] ![这里写图片描述][70 2] [java]: ht

深藏阁楼爱情的钟/ 2022年05月19日 03:50/ 0 赞/ 241 阅读

相关 Java Concurrency in Depth - 1

Java comes with strong support for multi-threading and concurrency, which makes it easy

r囧r小猫/ 2022年05月15日 10:48/ 0 赞/ 98 阅读

相关 Java Concurrency (1)

Memory that can be shared betweenthreads is called shared memory or heap memory. The te

àì夳堔傛蜴生んèń/ 2022年03月31日 02:46/ 0 赞/ 125 阅读