Java in a Nutshell

418 Pages·2014·7.136 MB·English

by  Benjamin J Evans, David Flanagan

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Java in a Nutshell vers diti
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The latest edition of Java in a Nutshell is designed to “ In a world of blogged EDITION a
8
help experienced Java programmers get the most out
opinions and javadoc’d
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of Java 7 and 8, but it’s also a learning path for new
references, this latest
developers. Chock full of examples that demonstrate a
how to take complete advantage of modern Java APIs edition is still the
v
and development best practices, the first section of simplest and most
this thoroughly updated book provides a fast-paced,
definitive way to cut a
no-fluff introduction to the Java programming language
through to the answers
and the core runtime aspects of the Java platform.
you need.” i
The second section is a reference to core concepts n
and APIs that shows you how to perform real —Kevlin Henney
programming work in the Java environment. consultant, author, speaker,
editor of 97 Things Every a
Programmer Should Know
■ Get up to speed on language details,
including Java 8 changes N
■ Learn object-oriented programming, using
basic Java syntax u
Benjamin J. Evans is the
■ Explore generics, enumerations, cofounder and Technology
annotations, and lambda expressions Fellow of jClarity, a startup that t J J aavvaa
delivers performance tools to help s
■ Understand basic techniques used in development & ops teams. He is a
object-oriented design Java Champion; JavaOne Rockstar; h
coauthor of The Well-Grounded
■ Examine concurrency and memory, and
Java Developer (Manning); and e
how they’re intertwined
a regular public speaker on the
■ Work with Java collections and handle Java platform, performance, l
concurrency, and related topics. l
common data formats
David Flanagan, senior staff
■ Delve into Java’s latest I/O APIs, including
frontend software engineer at
asynchronous channels iinn aa NNuuttsshheellll
Mozilla, has written several books
■ Use Nashorn to execute JavaScript on the for O’Reilly, including JavaScript:
The Definitive Guide, jQuery Pocket
Java Virtual Machine
Reference, The Ruby Programming F
■ Become familiar with development tools in Language, and previous editions of laEv
n
OpenJDK Java in a Nutshell. aan
g
s
an & A DESKTOP QUICK REFERENCE
PROGRAMMING/JAVA Twitter: @oreillymedia
facebook.com/oreilly
US $59.99 CAN $62.99
ISBN: 978-1-449-37082-4
Benjamin J. Evans & David Flanagan
6
t
h
C E
o
Java in a Nutshell vers diti
J o
SIXTH av n
The latest edition of Java in a Nutshell is designed to “ In a world of blogged EDITION a
8
help experienced Java programmers get the most out
opinions and javadoc’d
J
of Java 7 and 8, but it’s also a learning path for new
references, this latest
developers. Chock full of examples that demonstrate a
how to take complete advantage of modern Java APIs edition is still the
v
and development best practices, the first section of simplest and most
this thoroughly updated book provides a fast-paced,
definitive way to cut a
no-fluff introduction to the Java programming language
through to the answers
and the core runtime aspects of the Java platform.
you need.” i
The second section is a reference to core concepts n
and APIs that shows you how to perform real —Kevlin Henney
programming work in the Java environment. consultant, author, speaker,
editor of 97 Things Every a
Programmer Should Know
■ Get up to speed on language details,
including Java 8 changes N
■ Learn object-oriented programming, using
basic Java syntax u
Benjamin J. Evans is the
■ Explore generics, enumerations, cofounder and Technology
annotations, and lambda expressions Fellow of jClarity, a startup that t J J aavvaa
delivers performance tools to help s
■ Understand basic techniques used in development & ops teams. He is a
object-oriented design Java Champion; JavaOne Rockstar; h
coauthor of The Well-Grounded
■ Examine concurrency and memory, and
Java Developer (Manning); and e
how they’re intertwined
a regular public speaker on the
■ Work with Java collections and handle Java platform, performance, l
concurrency, and related topics. l
common data formats
David Flanagan, senior staff
■ Delve into Java’s latest I/O APIs, including
frontend software engineer at
asynchronous channels iinn aa NNuuttsshheellll
Mozilla, has written several books
■ Use Nashorn to execute JavaScript on the for O’Reilly, including JavaScript:
The Definitive Guide, jQuery Pocket
Java Virtual Machine
Reference, The Ruby Programming F
■ Become familiar with development tools in Language, and previous editions of laEv
n
OpenJDK Java in a Nutshell. aan
g
s
an & A DESKTOP QUICK REFERENCE
PROGRAMMING/JAVA Twitter: @oreillymedia
facebook.com/oreilly
US $59.99 CAN $62.99
ISBN: 978-1-449-37082-4
Benjamin J. Evans & David Flanagan
JAVA
IN A NUTSHELL
Sixth Edition
Benjamin J. Evans and David Flanagan
Java in a Nutshell
by Benjamin J. Evans and David Flanagan
Copyright © 2015 Benjamin J. Evans and David Flanagan. All rights reserved.
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[LSI]
This book is dedicated to all who teach peace and resist violence.

Table of Contents
Foreword. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xi
Preface. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . xiii
Part I. Introducing Java
1. Introduction to the Java Environment. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
The Language, the JVM, and the Ecosystem 3
A Brief History of Java and the JVM 7
The Lifecycle of a Java Program 9
Java Security 11
Comparing Java to Other Languages 11
Answering Some Criticisms of Java 13
2. Java Syntax from the Ground Up. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17
Java Programs from the Top Down 18
Lexical Structure 18
Primitive Data Types 22
Expressions and Operators 30
Statements 46
Methods 66
Introduction to Classes and Objects 72
Arrays 77
Reference Types 84
Packages and the Java Namespace 88
Java File Structure 93
Defining and Running Java Programs 94
Summary 95
vii
3. Object-Oriented Programming in Java. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 97
Overview of Classes 97
Fields and Methods 100
Creating and Initializing Objects 106
Subclasses and Inheritance 110
Data Hiding and Encapsulation 121
Abstract Classes and Methods 128
Modifier Summary 132
4. The Java Type System. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 135
Interfaces 136
Java Generics 142
Enums and Annotations 151
Nested Types 155
Lambda Expressions 171
Conclusion 174
5. Introduction to Object-Oriented Design in Java. . . . . . . . . . . . . . . . . . . . . . . 177
Java Values 177
Important Methods of java.lang.Object 178
Aspects of Object-Oriented Design 183
Exceptions and Exception Handling 193
Safe Java Programming 195
6. Java’s Approach to Memory and Concurrency. . . . . . . . . . . . . . . . . . . . . . . . . 197
Basic Concepts of Java Memory Management 197
How the JVM Optimizes Garbage Collection 201
The HotSpot Heap 203
Finalization 206
Java’s Support for Concurrency 208
Working with Threads 218
Summary 219
Part II. Working with the Java Platform
7. Programming and Documentation Conventions. . . . . . . . . . . . . . . . . . . . . . . 223
Naming and Capitalization Conventions 223
Practical Naming 225
Java Documentation Comments 226
Conventions for Portable Programs 235
viii | Table of Contents
8. Working with Java Collections. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
Introduction to Collections API 239
Lambda Expressions in the Java Collections 258
Conclusion 266
9. Handling Common Data Formats. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 267
Text 267
Numbers and Math 275
Java 8 Date and Time 280
Conclusion 287
10. File Handling and I/O. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 289
Classic Java I/O 289
Modern Java I/O 295
NIO Channels and Buffers 298
Async I/O 301
Networking 304
11. Classloading, Reflection, and Method Handles. . . . . . . . . . . . . . . . . . . . . . . . 311
Class Files, Class Objects, and Metadata 311
Phases of Classloading 313
Secure Programming and Classloading 315
Applied Classloading 317
Reflection 320
Dynamic Proxies 325
Method Handles 326
12. Nashorn. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Introduction to Nashorn 331
Executing JavaScript with Nashorn 332
Nashorn and javax.script 340
Advanced Nashorn 342
Conclusion 347
13. Platform Tools and Profiles. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 349
Command-Line Tools 349
VisualVM 362
Java 8 Profiles 367
Conclusion 372
Index. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 373
Table of Contents | ix