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ISBN 978-1-4302-5722-6 ISB N 978-1-4302-5723-3 (eBook) www.it-ebooks.info To Amaury. www.it-ebooks.info v Contents at a Glance About the Author xvii About the Technical Reviewers xix Acknowledgments xxi Introduction xxiii Chapter 1: Getting Started With Java N 1 Chapter 2: Learning Language Fundamentals N 21 Chapter 3: Discovering Classes and Objects N 63 Chapter 4: Discovering Inheritance, Polymorphism, and Interfaces N 105 Chapter 5: Mastering Advanced Language Features Part 1 N 153 Chapter 6: Mastering Advanced Language Features Part 2 N 197 Chapter 7: Exploring the Basic APIs Part 1 N 247 Chapter 8: Exploring the Basic APIs Part 2 N 279 Chapter 9: Exploring the Collections Framework N 327 Chapter 10: Exploring Additional Utility APIs N 407 Chapter 11: Performing Classic I/O N 449 Chapter 12: Accessing Networks N 525 www.it-ebooks.info vi Contents at a Glance Chapter 13: Migrating to New I/O N 561 Chapter 14: Accessing Databases N 603 Appendix A: Solutions to Exercises N 643 Appendix B: Four of a Kind N 713 Index 735 www.it-ebooks.info vii Contents About the Author xvii About the Technical Reviewers xix Acknowledgments xxi Introduction xxiii Chapter 1: Getting Started With Java N 1 What Is Java? 2 Java Is a Language 2 Java Is a Platform 4 Java SE, Java EE, Java ME, and Android 5 Installing and Exploring the JDK 6 Installing and Exploring the Eclipse IDE 12 Overview of Java APIs 16 Language-Support and Other Language-Oriented APIs 17 Collections-Oriented APIs 17 Additional Utility APIs 17 Classic I/O APIs 17 Networking APIs 18 www.it-ebooks.info viii Contents New I/O APIs 18 Database APIs 18 Summary 19 Chapter 2: Learning Language Fundamentals N 21 Learning Comments 21 Single-Line Comments 22 Multiline Comments 22 Javadoc Comments 23 Learning Identifiers 25 Learning Types 26 Primitive Types 26 User-Defined Types 28 Array Types 28 Learning Variables 29 Learning Expressions 30 Simple Expressions 30 Compound Expressions 34 Learning Statements 46 Assignment Statements 46 Decision Statements 47 Loop Statements 51 Break and Labeled Break Statements 56 Continue and Labeled Continue Statements 58 Summary 60 Chapter 3: Discovering Classes and Objects N 63 Declaring Classes and Instantiating Objects 63 Declaring Classes 64 Instantiating Objects with the New Operator and a Constructor 64 Specifying Constructor Parameters and Local Variables 65 www.it-ebooks.info ixContents Encapsulating State and Behaviors 69 Representing State via Fields 70 Representing Behaviors via Methods 75 Hiding Information 84 Initializing Classes and Objects 89 Class Initializers 89 Instance Initializers 91 Initialization Order 93 Collecting Garbage 96 Revisiting Arrays 99 Summary 104 Chapter 4: Discovering Inheritance, Polymorphism, and Interfaces N 105 Building Class Hierarchies 105 Extending Classes 106 The Ultimate Superclass 112 Composition 122 The Trouble with Implementation Inheritance 122 Changing Form 126 Upcasting and Late Binding 127 Abstract Classes and Abstract Methods 131 Downcasting and Runtime Type Identification 133 Covariant Return Types 136 Formalizing Class Interfaces 139 Declaring Interfaces 139 Implementing Interfaces 140 Extending Interfaces 144 Why Use Interfaces? 146 Summary 152 www.it-ebooks.info x Contents Chapter 5: Mastering Advanced Language Features Part 1 N 153 Mastering Nested Types 153 Static Member Classes 153 Nonstatic Member Classes 157 Anonymous Classes 161 Local Classes 164 Interfaces within Classes 166 Mastering Packages 167 What Are Packages? 168 The Package Statement 169 The Import Statement 169 Searching for Packages and Types 170 Playing with Packages 172 Packages and JAR Files 176 Mastering Static Imports 177 Mastering Exceptions 179 What Are Exceptions? 179 Representing Exceptions in Source Code 179 Throwing Exceptions 184 Handling Exceptions 187 Performing Cleanup 190 Summary 195 Chapter 6: Mastering Advanced Language Features Part 2 N 197 Mastering Assertions 197 Declaring Assertions 198 Using Assertions 199 Avoiding Assertions 205 Enabling and Disabling Assertions 206 www.it-ebooks.info [...]... that run on desktops Java SE is also used to develop applets, which are programs that run in web browsers Java Platform, Enterprise Edition (Java EE): The Java platform for developing enterprise-oriented applications and servlets, which are server programs that conform to Java EE’s Servlet API Java EE is built on top of Java SE Java Platform, Micro Edition (Java ME): The Java platform for developing MIDlets,... platform (and possibly stealing sensitive information) Java SE, Java EE, Java ME, and Android Developers use different editions of the Java platform to create Java programs that run on desktop computers, web browsers, web servers, mobile information devices (e.g., feature phones), and embedded devices (e.g., television set-top boxes): Java Platform, Standard Edition (Java SE): The Java platform for. .. introduce you to Java by first focusing on Java s dual nature (language and platform) I then briefly introduce you to Oracle’s Java SE, Java EE, and Java ME editions of the Java development software, as well as Google’s Android edition You next learn how to download and install the Java SE Development Kit (JDK) and learn some Java basics by developing and playing with a pair of simple Java applications... a copy of Beginning Android 4 by Grant Allen (Apress, 2012) and start learning how to develop Android apps In that book, you learn Android basics and how to create “innovative and salable applications for Android 4 mobile devices.” Rather than give a few superficial details of Android development, Learn Java for Android Development Second Edition concentrates on teaching you the Java language and APIs... With Java In this book, I cover the Java language (supported by Java SE and Android) and various Java SE APIs that are also supported by Android I focus on language features through Java version 5 and on Java APIs through Java 5, with a small amount of Java 6 Note Google’s Android platform is based on an open source release of Java 5 It doesn’t officially recognize language features newer than Java. .. understand Java, how can you proceed to understand Android? Note I also recommend that you check out the second edition of Android Recipes (see www.apress.com/9781430246145) Although the content of that book largely contains independent recipes for learning all kinds of things about Android, Chapter 1 contains a summarized and rapid introduction to Android app development You will learn much about Android. .. which are programs that run on mobile information devices, and Xlets, which are programs that run on embedded devices Developers also use a special Google-created edition of the Java platform (see http://developer .android. com/index.html) to create Android apps that run on Android- enabled devices This edition is known as the Android platform Google’s Android platform presents a Dalvik virtual machine... written in Java and interact with many of the standard Java APIs (e.g., threading and input/output APIs) I wrote Learn Java for Android Development to give you a solid Java foundation that you can later extend with knowledge of Android architecture, API, and tool specifics This book will give you a strong grasp of the Java language and many important APIs that are fundamental to Android apps and other Java. .. develop Java applications (and, eventually, Android apps), I provide you with a high-level overview of various Java APIs that you can access from your Java applications and Android apps In subsequent chapters, you’ll explore these and other useful APIs in greater detail J Friesen, Learn Java for Android Development © Jeff Friesen 2013 1 www.it-ebooks.info 2 CHAPTER 1: Getting Started With Java Note... originated by Sun Microsystems In this section, I briefly describe this language and reveal what it means for Java to be a platform To meet various needs, Sun organized Java into three main editions: Java SE, Java EE, and Java ME This section also briefly explores each of these editions, along with Android Note Java has an interesting history that dates back to December 1990 At that time, James Gosling, Patrick . www.it-ebooks.info Learn Java for Android Development Second Edition Je Friesen Apress www.it-ebooks.info Learn Java for Android Development Copyright. xxiii Chapter 1: Getting Started With Java N 1 What Is Java? 2 Java Is a Language 2 Java Is a Platform 4 Java SE, Java EE, Java ME, and Android 5 Installing and Exploring