Java - The Comprehensive Guide

This is the up-to-date, practical guide to Java you've been looking for! Whether you're a beginner, you're switching to Java from another language, or you're just looking to brush up on your Java skills, this is the only book you need. You'll get a thorough grounding in the basics of the Java language, including classes, objects, arrays, strings, and exceptions. You'll also learn about more advanced topics: threads, algorithms, XML, JUnit testing, and much more. This book belongs on every Java programmer's shelf!

Highlights:

• Classes and objects


• Arrays


• Exception handling


• Object-oriented programming


• Characters and strings


• Generics


• Class library


• Concurrent programming


• Data structures


• Lambda expressions


• JUnit testing


• JDK tools

... Preface ... 31


... Target Group ... 31


... What This Book Is Not ... 31


... My Life and Java, Or "Why a Java Book?" ... 32


... Software and Versions ... 33


... Which Java Version to Use ... 33


... Using This Book to Learn ... 33


... Personal Learning Strategies ... 34


... Focusing on the Essentials ... 35


... Special Sections ... 35


... Tasks ... 36


... Structure of This Book ... 36


... Conventions ... 38


... Program Listings ... 40


... Application Programming Interface Documentation in This Book ... 40


... Executable Programs ... 41


... Acknowledgments ... 41


... Resources for This Book ... 42


... Feedback ... 42


1 ... Introduction ... 43


1.1 ... Historical Background ... 43


1.2 ... On the Popularity of Java: The Key Features ... 45


1.3 ... Java versus Other Languages* ... 56


1.4 ... Further Development and Losses ... 59


1.5 ... Java Platforms ... 62


1.6 ... Java Platform, Standard Edition, Implementations ... 67


1.7 ... Installing the Java Development Kit ... 69


1.8 ... Compiling and Testing the First Program ... 71


1.9 ... Development Environments ... 75


1.10 ... Further Reading ... 81


2 ... Imperative Language Concepts ... 83


2.1 ... Elements of the Java Programming Language ... 83


2.2 ... From Classes to Statements ... 91


2.3 ... Data Types, Typing, Variables, and Assignments ... 102


2.4 ... Expressions, Operands, and Operators ... 119


2.5 ... Conditional Statements or Case Distinctions ... 142


2.6 ... Always the Same with Loops ... 160


2.7 ... Methods of a Class ... 177


2.8 ... Further Reading ... 200


3 ... Classes and Objects ... 201


3.1 ... Object-Oriented Programming ... 201


3.2 ... Members of a Class ... 203


3.3 ... Natural Modeling Using Unified Modeling Language* ... 204


3.4 ... Creating New Objects ... 206


3.5 ... ZZZZZnake ... 218


3.6 ... Tying Packages, Imports, and Compilation Units ... 220


3.7 ... Using References, Diversity, Identity, and Equality ... 228


3.8 ... Further Reading ... 239


4 ... Arrays and Their Areas of Use ... 241


4.1 ... Simple Field Work ... 241


4.2 ... The Extended for Loop ... 252


4.3 ... A Method with a Variable Number of Arguments ... 256


4.4 ... Multidimensional Arrays* ... 259


4.5 ... Library Support for Arrays ... 264


4.6 ... Using the Arrays Class for Comparing, Filling, Searching, and Sorting ... 267


4.7 ... The Entry Point for the Runtime System: main(...) ... 281


4.8 ... Further Reading ... 285


5 ... Handling Characters and Strings ... 287


5.1 ... From ASCII via ISO-8859-1 to Unicode ... 287


5.2 ... Data Types for Characters and Strings ... 295


5.3 ... The Character Class ... 296


5.4 ... Strings ... 301


5.5 ... The String Class and Its Methods ... 303


5.6 ... Mutable Strings with StringBuilder and StringBuffer ... 333


5.7 ... CharSequence as Base Type ... 342


5.8 ... Converting Primitives and Strings ... 345


5.9 ... Concatenating Strings ... 353


5.10 ... Decomposing Strings ... 355


5.11 ... Formatting Outputs ... 360


5.12 ... Further Reading ... 367


6 ... Writing Custom Classes ... 369


6.1 ... Declaring Custom Classes with Members ... 369


6.2 ... Privacy and Visibility ... 380


6.3 ... One for All: Static Methods and Class Variables ... 390


6.4 ... Constants and Enumerations ... 397


6.5 ... Creating and Destroying Objects ... 405


6.6 ... Class and Object Initialization* ... 418


6.7 ... Conclusion ... 426


7 ... Object-Oriented Relationship ... 427


7.1 ... Associations between Objects ... 427


7.2 ... Inheritance ... 436


7.3 ... Types in Hierarchies ... 447


7.4 ... Overriding Methods ... 457


7.5 ... Testing Dynamic Bindings ... 463


7.6 ... Final Classes and Final Methods ... 466


7.7 ... Abstract Classes and Abstract Methods ... 468


7.8 ... Further Information on Overriding and Dynamic Binding ... 476


7.9 ... A Programming Task ... 482


8 ... Interfaces, Enumerations, Sealed Classes, Records ... 483


8.1 ... Interfaces ... 483


8.2 ... Enumeration Types ... 513


8.3 ... Sealed Classes and Interfaces ... 523


8.4 ... Records ... 529


9 ... There Must Be Exceptions ... 539


9.1 ... Fencing In Problem Areas ... 539


9.2 ... Redirecting Exceptions and throws at the Head of Methods/Constructors ... 549


9.3 ... The Class Hierarchy of Exceptions ... 550


9.4 ... Final Handling Using finally ... 558


9.5 ... Triggering Custom Exceptions ... 564


9.6 ... try with Resources (Automatic Resource Management) ... 579


9.7 ... Special Features of Exception Handling* ... 588


9.8 ... Hard Errors: Error* ... 593


9.9 ... Assertions* ... 594


9.10 ... Conclusion ... 597


10 ... Nested Types ... 599


10.1 ... Nested Classes, Interfaces, and Enumerations ... 599


10.2 ... Static Nested Types ... 601


10.3 ... Non-Static Nested Types ... 603


10.4 ... Local Classes ... 605


10.5 ... Anonymous Inner Classes ... 607


10.6 ... Nests ... 613


10.7 ... Conclusion ... 614


11 ... Special Types of Java SE ... 615


11.1 ... Object Is the Mother of All Classes ... 616


11.2 ... Weak References and Cleaners ... 638


11.3 ... The java.util.Objects Utility Class ... 639


11.4 ... Comparing Objects and Establishing Order ... 643


11.5 ... Wrapper Classes and Autoboxing ... 651


11.6 ... Iterator, Iterable* ... 670


11.7 ... Annotations in Java Platform, Standard Edition ... 677


11.8 ... Further Reading ... 682


12 ... Generics ... 683


12.1 ... Introduction to Java Generics ... 683


12.2 ... Implementing Generics, Type Erasure, and Raw Types ... 699


12.3 ... Restricting Types via Bounds ... 706


12.4 ... Type Parameters in the throws Clause* ... 710


12.5 ... Inheritance and Invariance with Generics ... 713


12.6 ... Consequences of Type Erasure: Type Tokens, Arrays* ... 725


12.7 ... Further Reading ... 729


13 ... Lambda Expressions and Functional Programming ... 731


13.1 ... Functional Interfaces and Lambda Expressions ... 731


13.2 ... Method References ... 755


13.3 ... Constructor References ... 759


13.4 ... Functional Programming ... 762


13.5 ... Functional Interfaces from the java.util.function Package ... 770


13.6 ... Optional Is Not a Non-Starter ... 784


13.7 ... What Is So Functional Now? ... 795


13.8 ... Further Reading ... 797


14 ... Architecture, Design, and Applied Object Orientation ... 799


14.1 ... SOLID Modeling ... 799


14.2 ... Architecture, Design, and Implementation ... 803


14.3 ... Design Patterns ... 803


14.4 ... Further Reading ... 811


15 ... Java Platform Module System ... 813


15.1 ... Class Loader and Module/Classpath ... 813


15.2 ... Importing Modules ... 819


15.3 ... Developing Custom Modules ... 825


15.4 ... Further Reading ... 833


16 ... The Class Library ... 835


16.1 ... The Java Class Philosophy ... 835


16.2 ... Simple Time Measurement and Profiling* ... 842


16.3 ... The Class Class ... 843


16.4 ... The Utility Classes System and Members ... 846


16.5 ... The Languages of Different Countries ... 853


16.6 ... Overview of Important Date Classes ... 857


16.7 ... Date-Time API ... 860


16.8 ... Logging with Java ... 864


16.9 ... Maven: Resolving Build Management and Dependencies ... 867


16.10 ... Further Reading ... 869


17 ... Introduction to Concurrent Programming ... 871


17.1 ... Concurrency and Parallelism ... 871


17.2 ... Generating Existing Threads and New Threads ... 875


17.3 ... Thread Members and States ... 882


17.4 ... Enter the Executor ... 893


17.5 ... Further Reading ... 907


18 ... Introduction to Data Structures and Algorithms ... 909


18.1 ... Lists ... 909


18.2 ... Sets ... 928


18.3 ... Associative Memory ... 938


18.4 ... The Stream API ... 944


18.5 ... Creating a Stream ... 947


18.6 ... Terminal Operations ... 951


18.7 ... Intermediary Operations ... 962


18.8 ... Further Reading ... 968


19 ... Files and Data Streams ... 969


19.1 ... Old and New Worlds in java.io and java.nio ... 969


19.2 ... File Systems and Paths ... 970


19.3 ... Random Access Files ... 980


19.4 ... Base Classes for Input/Output ... 985


19.5 ... Reading from Files and Writing to Files ... 996


19.6 ... Further Reading ... 1003


20 ... Introduction to Database Management with JDBC ... 1005


20.1 ... Relational Databases and Java Access ... 1005


20.2 ... A Sample Query ... 1008


20.3 ... Further Reading ... 1009


21 ... Bits and Bytes, Mathematics and Money ... 1011


21.1 ... Bits and Bytes ... 1011


21.2 ... Floating Point Arithmetic in Java ... 1025


21.3 ... The Members of the Math Class ... 1031


21.4 ... Accuracy and the Value Range of Type and Overflow Control* ... 1042


21.5 ... Random Numbers: Random, ThreadLocalRandom, and SecureRandom ... 1046


21.6 ... Large Numbers* ... 1051


21.7 ... Money and Currency ... 1064


21.8 ... Further Reading ... 1066


22 ... Testing with JUnit ... 1067


22.1 ... Software Tests ... 1067


22.2 ... The JUnit Testing Framework ... 1068


22.3 ... Java Assertion Libraries and AssertJ ... 1081


22.4 ... Structure of Large Test Cases ... 1083


22.5 ... Good Design Enables Effective Testing ... 1085


22.6 ... Dummy, Fake, Stub, and Mock ... 1087


22.7 ... JUnit Extensions and Testing Add-Ons ... 1089


22.8 ... Further Reading ... 1089


23 ... The Tools of the JDK ... 1091


23.1 ... Overview ... 1091


23.2 ... Translating Java Sources ... 1092


23.3 ... The Java Runtime Environment ... 1093


23.4 ... Documentation Comments with Javadoc ... 1096


23.5 ... The JAR Archive Format ... 1105


23.6 ... Further Reading ... 1107


... The Author ... 1109


... Index ... 1111