Java

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

Work with expressions, statements, classes, objects, and much more

Autorentext
Christian Ullenboom is an Oracle-certified Java programmer and has been a trainer and consultant for Java technologies and object-oriented analysis and design since 1997.

Inhalt
... 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 I…