【翻译二】java--并发之进程与线程
In concurrent programming, there are two basic units of execution: processes and threads. In the Java programming language, concurrent programming is mostly concerned with threads. However, processes are also important.
A computer system normally has many active processes and threads. This is true even in systems that only have a single execution core, and thus only have one thread actually executing at any given moment. Processing time for a single core is shared among processes and threads through an OS feature called time slicing.
It's becoming more and more common for computer systems to have multiple processors or processors with multiple execution cores. This greatly enhances a system's capacity for concurrent execution of processes and threads — but concurrency is possible even on simple systems, without multiple processors or execution cores.
Processes
A process has a self-contained execution environment. A process generally has a complete, private set of basic run-time resources; in particular, each process has its own memory space.
Processes are often seen as synonymous with programs or applications. However, what the user sees as a single application may in fact be a set of cooperating processes. To facilitate communication between processes, most operating systems support Inter Process Communication (IPC) resources, such as pipes and sockets. IPC is used not just for communication between processes on the same system, but processes on different systems.
Most implementations of the Java virtual machine run as a single process. A Java application can create additional processes using a ProcessBuilder
object. Multiprocess applications are beyond the scope of this lesson.
Threads
Threads are sometimes called lightweight processes. Both processes and threads provide an execution environment, but creating a new thread requires fewer resources than creating a new process.
Threads exist within a process — every process has at least one. Threads share the process's resources, including memory and open files. This makes for efficient, but potentially problematic, communication.
Multithreaded execution is an essential feature of the Java platform. Every application has at least one thread — or several, if you count "system" threads that do things like memory management and signal handling. But from the application programmer's point of view, you start with just one thread, called the main thread. This thread has the ability to create additional threads, as we'll demonstrate in the next section.
【翻译二】java--并发之进程与线程的更多相关文章
- Java中的进程和线程
Java中的进程与线程 一:进程与线程 概述:几乎任何的操作系统都支持运行多个任务,通常一个任务就是一个程序,而一个程序就是一个进程.当一个进程运行时,内部可能包括多个顺序执行流,每个顺序执行流就是 ...
- Java中的进程与线程(总结篇)
详细文档: Java中的进程与线程.rar 474KB 1/7/2017 6:21:15 PM 概述: 几乎任何的操作系统都支持运行多个任务,通常一个任务就是一个程序,而一个程序就是一个进程.当一个进 ...
- java 获取当前进程id 线程id
java 获取当前进程id 线程id RuntimeMXBean (Java Platform SE 8 ) https://docs.oracle.com/javase/8/docs/api/j ...
- Java 多线程详解(二)------如何创建进程和线程
Java 多线程详解(一)------概念的引入:http://www.cnblogs.com/ysocean/p/6882988.html 在上一篇博客中,我们已经介绍了并发和并行的区别,以及进程和 ...
- Java并发编程:进程和线程的由来(转)
Java多线程基础:进程和线程之由来 在前面,已经介绍了Java的基础知识,现在我们来讨论一点稍微难一点的问题:Java并发编程.当然,Java并发编程涉及到很多方面的内容,不是一朝一夕就能够融会贯通 ...
- JAVA基础知识|进程与线程
一.什么是进程?什么是线程? 操作系统可以同时支持多个程序的运行,而一个程序可以狭义的认为就是一个进程.在一个进程的内部,可能包含多个顺序执行流,而每个执行流就对应一个线程. 1.1.进程 进程:是计 ...
- (转)java中的进程与线程
(转自地址http://www.ibm.com/developerworks/cn/java/j-lo-processthread/) Java 进程的建立方法 在 JDK 中,与进程有直接关系的类为 ...
- Java多线程之进程和线程
在并发编程中有两个基本的概率就是进程和线程.在Java编程中并发编程更多的是关注线程.但是进程也是很重要的. 一个计算机一般会有很多活跃的进程和线程.有一点是没有疑问的在单核系统中,任何时候实际上都是 ...
- java中的进程与线程及java对象的内存结构【转】
原文地址:http://rainforc.iteye.com/blog/2039501 1.实现线程的三种方式: 使用内核线程实现 内核线程(Kernel Thread, KLT)就是 ...
随机推荐
- BZOJ 3270: 博物馆
Sol 期望DP+高斯消元. 根据本题题意列出期望方程\[E(i,j)=(1-p_i)(1-p_j)E(u,v)+(1-p_i)p_jE(u,j)+p_i(1-p_j)E(i,v)+p_ip_jE(i ...
- 求教Sublime Text2 SublimeLinter插件安装问题
昨天装了 SublimeLinter插件(代码语法检测),这个事插件的地址:https://github.com/Kronuz/SublimeLinter 按照作者的介绍配置了一下,发现语法检测不起作 ...
- NET程序内存分析工具CLRProfiler的使用(性能测试)
http://blog.csdn.net/wy3552128/article/details/8158938 大家都知道.net有一套自己的内存(垃圾)回收机制,除非有一些数据(方法)长期占有内存不随 ...
- Android之Activity之间跳转
本人自学Android,想到什么就写点什么.主要是怕忘了,哈哈~请观者不要建议~ 今天写点Android窗口之间的跳转以及自己理解: 1.Android中窗口之间的跳转,就是Activity之间的跳转 ...
- Core Data 多线程时多个context使用
原文地址:http://blog.csdn.net/willmomo/article/details/19759413 写的非常好!我这里截取一点重要的,备份,请去原地址阅读! 本人去年10月份才接触 ...
- pfsense 企业应用实例
从萌生更换公司网关的想法,到选择.测试.部署陆陆续续用时两个月有余.选择的标准是open and free.这期间不断在查阅一些资料,测试了7.8个各开源防火墙产品.这些产品中大多是基于linux,少 ...
- VS2010工程文件减肥
由于VS2010中新增加了sdf和ipch文件等浏览数据库来支持智能浏览感知编辑.显示类视图等,使得随便一个小工程就上百兆,很占用空间也不方便工程项目的打包备份.为了不使用数据库以减小VS2010中的 ...
- cxGrid 增加序号 (非数据库绑定模式) (测试通过)
cxGrid 增加序号 (非数据库绑定模式) ----------------------------------- 1. 选在 adoQuery 控件 , 鼠标右键菜单中 选择 Fields Edi ...
- Python批量修改文件名-后缀
LyncLynn用途: 批量修改文件格式,文件名后缀. #Version: V1.0 #Author:lynclynn #Description:Change the filename #Create ...
- 2101 Problem A Snake Filled
题目描述 “What a boring world!”Julyed felt so bored that she began to write numbers on the coordinate pa ...