Preface

J

AVA was originally called Oak, and designed for use in embedded consumer 

electronic applications by James Gosling. After several years of experience with

the language, and significant contributions by Ed Frank, Patrick Naughton,

Jonathan Payne, and Chris Warth it was retargeted to the Internet, renamed Java,

and substantially revised to be the language specified here. The final form of the

language was defined by James Gosling, Bill Joy, Guy Steele, Richard Tuck,

Frank Yellin, and Arthur van Hoff, with help from Graham Hamilton, Tim Lind 

holm and many other friends and colleagues.

Java is a general purpose concurrent class based object oriented program 

ming language, specifically designed to have as few implementation dependencies

as possible. Java allows application developers to write a program once and then

be able to run it everywhere on the Internet.

This book attempts a complete specification of the syntax and semantics of

the Java language and the core packages

java.lang

,

java.io

, and

java.util

 of

its Application Programming Interface. We intend that the behavior of every lan 

guage construct is specified here, so that all implementations of Java will accept

the same programs. Except for timing dependencies or other non determinisms

and given sufficient time and sufficient memory space, a Java program should

compute the same result on all machines and in all implementations.

We believe that Java is a mature language, ready for widespread use. Never 

theless, we expect some evolution of the language in the years to come. We intend

to manage this evolution in a way that is completely compatible with existing

applications. To do this, we intend to make relatively few new versions of the lan 

guage, and to distinguish each new version with a different filename extension.

Java compilers and systems will be able to support the several versions simultan 

nously, with complete compatibility.

Much research and experimentation with Java is already underway. We

encourage this work, and will continue to cooperate with external groups to

explore improvements to Java. For example, we have already received several

interesting proposals for parameterized types. In technically difficult areas, near

the state of the art, this kind of research collaboration is essential.

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