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