INTRODUCTION

Example Programs

1.1

tialized to a default value, Java does not automatically initialize local variables in

order to avoid masking programming errors.

Chapter 17 describes the semantics of Java threads and locks, which are based

on the monitor based concurrency originally introduced with the Mesa program 

ming language. Java specifies a memory model for shared memory multiproces 

sors that supports high performance implementations.

Chapter 18 describes the facilities for automatically generating documenta 

tion from special comments in Java source code.

Chapter 19 presents a LALR(1) syntactic grammar for Java, and describes the

differences between this grammar and the expository grammar used in the body of

the language specification that precedes it.

Chapters 20 through 22 are the reference manual for the core of the standard

Java Application Programming Interface. These packages must be included in all

general purpose Java systems.

Chapter 20 describes the package

java.lang

. The types defined in

java.lang

 are automatically imported to be available without qualification in all

Java programs. They include the primordial class

Object

, which is a superclass of

all other classes; classes such as

Integer

and

Float

, which wrap the primitive

types inside objects; exceptions and errors defined by the language and the Java

Virtual Machine;

Thread

 support; metalinguistic classes such as

Class

 and

ClassLoader

; and the class

System

, which abstracts the host system.

Chapter 21 describes the package

java.util

, which defines a few basic util 

ity classes, such as a hashtable class and a pseudo random number generator.

Chapter 22 describes the package

java.io

, which defines basic input/output

facilities, including random access files and streams of values of primitive types.

The book concludes with an index, credits for quotations used in the book,

and a colophon describing how the book was created.

1.1   Example Programs

Most of the example programs given in the text are ready to be executed by a Java

system and are similar in form to:

class Test {

public static void main(String[] args) {

for (int i = 0; i < args.length; i++)

System.out.print(i == 0 ? args[i] : " " + args[i]);

System.out.println();

}

}

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