OCP Oracle Certified Professional Java SE 21 Developer Study Guide: Exam 1Z0-830

Table of Contents....2

Title Page....16

Copyright....17

Dedication....19

Acknowledgments....20

About the Authors....22

About the Technical Editor....24

About the Technical Proofreader....24

Introduction....26

Understanding the Exam....26

Reading This Book....34

Studying for the Exam....40

Applying Test-Taking Strategies....44

Taking the Exam....49

Objective Map....51

How to Contact the Publisher....53

Assessment Test....54

Answers to Assessment Test....69

Chapter 1: Building Blocks....76

Learning About the Environment....76

Understanding the Class Structure....78

Writing a main() Method....82

Understanding Package Declarations and Imports....86

Creating Objects....96

Understanding Data Types....100

Declaring Variables....111

Initializing Variables....115

Managing Variable Scope....122

Destroying Objects....125

Summary....129

Exam Essentials....130

Review Questions....131

Chapter 2: Operators....141

Understanding Java Operators....141

Applying Unary Operators....145

Working with Binary Arithmetic Operators....149

Assigning Values....156

Comparing Values....165

Making Decisions with the Ternary Operator....176

Summary....178

Exam Essentials....179

Review Questions....180

Chapter 3: Making Decisions....189

Creating Decision-Making Statements....189

Building switch Statements and Expressions....201

Writing while Loops....223

Constructing for Loops....227

Controlling Flow with Branching....235

Summary....245

Exam Essentials....246

Review Questions....247

Chapter 4: Core APIs....264

Creating and Manipulating Strings....264

Using the StringBuilder Class....283

Understanding Equality....291

Understanding Arrays....294

Calculating with Math APIs....310

Working with Dates and Times....315

Summary....337

Exam Essentials....338

Review Questions....339

Chapter 5: Methods....349

Designing Methods....349

Declaring Local and Instance Variables....361

Working with Varargs....365

Applying Access Modifiers....368

Accessing Static Data....378

Passing Data among Methods....389

Overloading Methods....396

Summary....403

Exam Essentials....404

Review Questions....405

Chapter 6: Class Design....417

Understanding Inheritance....418

Creating Classes....424

Declaring Constructors....430

Initializing Objects....443

Inheriting Members....453

Creating Abstract Classes....465

Creating Immutable Objects....475

Summary....479

Exam Essentials....481

Review Questions....483

Chapter 7: Beyond Classes....499

Implementing Interfaces....500

Working with Enums....518

Sealing Classes....525

Encapsulating Data with Records....532

Creating Nested Classes....548

Understanding Polymorphism....561

Summary....573

Exam Essentials....575

Review Questions....576

Chapter 8: Lambdas and Functional Interfaces....595

Writing Simple Lambdas....595

Coding Functional Interfaces....602

Using Method References....606

Working with Built-in Functional Interfaces....612

Working with Variables in Lambdas....627

Summary....632

Exam Essentials....633

Review Questions....634

Chapter 9: Collections and Generics....645

Using Common Collection APIs....645

Using the List Interface....652

Using the Set Interface....658

Using the Queue and Deque Interfaces....660

Using the Map Interface....663

Sorting Data....670

Introducing Sequenced Collections....680

Reviewing Collection Types....682

Working with Generics....686

Summary....700

Exam Essentials....701

Review Questions....702

Chapter 10: Streams....710

Returning an Optional....710

Using Streams....714

Working with Primitive Streams....733

Working with Advanced Stream Pipeline Concepts....740

Summary....754

Exam Essentials....754

Review Questions....755

Chapter 11: Exceptions and Localization....764

Understanding Exceptions....764

Recognizing Exception Classes....777

Handling Exceptions....784

Automating Resource Management....795

Formatting Values....806

Supporting Internationalization and Localization....813

Loading Properties with Resource Bundles....826

Summary....835

Exam Essentials....836

Review Questions....837

Chapter 12: Modules....852

Introducing Modules....852

Creating and Running a Modular Program....856

Updating Our Example for Multiple Modules....864

Diving into the Module Declaration....872

Creating a Service....878

Discovering Modules....888

Comparing Types of Modules....906

Migrating an Application....912

Summary....920

Exam Essentials....922

Review Questions....922

Chapter 13: Concurrency....933

Introducing Threads....934

Creating Threads with the Concurrency API....947

Writing Thread-Safe Code....961

Using Concurrent Collections....979

Identifying Threading Problems....983

Working with Parallel Streams....988

Summary....1001

Exam Essentials....1002

Review Questions....1003

Chapter 14: I/O....1018

Referencing Files and Directories....1019

Operating on File and Path....1026

Introducing I/O Streams....1050

Reading and Writing Files....1060

Serializing Data....1070

Interacting with Users....1082

Working with Advanced APIs....1089

Review of Key APIs....1103

Summary....1106

Exam Essentials....1107

Review Questions....1108

Appendix: Answers to Review Questions....1122

Chapter 1: Building Blocks....1123

Chapter 2: Operators....1128

Chapter 3: Making Decisions....1133

Chapter 4: Core APIs....1141

Chapter 5: Methods....1146

Chapter 6: Class Design....1151

Chapter 7: Beyond Classes....1160

Chapter 8: Lambdas and Functional Interfaces....1166

Chapter 9: Collections and Generics....1171

Chapter 10: Streams....1177

Chapter 11: Exceptions and Localization....1182

Chapter 12: Modules....1188

Chapter 13: Concurrency....1192

Chapter 14: I/O....1198

Index....1204

End User License Agreement....1371

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