26.1 Introduction

It would be nice if we could focus our attention on performing only one action at a time and performing it well, but that’s usually difficult to do. The human body performs a great variety of operations in parallel—or, as we’ll say throughout this chapter, concurrently. Respiration, blood circulation, digestion, thinking and walking, for example, can occur concurrently, as can all the senses—sight, touch, smell, taste and hearing.

Computers, too, can perform operations concurrently. It’s common for personal computers to compile a program, send a file to a printer and receive electronic mail messages over a network concurrently. Only computers that have multiple processors can truly execute multiple instructions concurrently. ...

Get Java How to Program (early objects), 9/e now with O’Reilly online learning.

O’Reilly members experience live online training, plus books, videos, and digital content from 200+ publishers.