Java All–in–One For Dummies

Doug Lowe is a master at simplifying complex tech topics. His four previous editions of Java All-in-One For Dummies have helped thousands of programmers master Java skills. Doug also serves as a one-man IT department for an engineering consulting firm.

Introduction 1


About This Book 2


Foolish Assumptions 2


Icons Used in This Book 3


Beyond the Book 4


Where to Go from Here 4


Book 1: Java Basics 5


Chapter 1: Welcome to Java 7


What Is Java, and Why Is It So Great? 8


Java versus Other Languages 12


Important Features of the Java Language 13


On the Downside: Java’s Weaknesses 16


Java Version Insanity 17


What’s in a Name? 19


Chapter 2: Installing and Using Java Tools 21


Downloading and Installing the Java Development Kit 22


Using Java’s Command-Line Tools 26


Using Java Documentation 32


Chapter 3: Working with TextPad 35


Downloading and Installing TextPad 35


Editing Source Files 36


Compiling a Program 39


Running a Java Program 40


Book 2: Programming Basics 43


Chapter 1: Java Programming Basics 45


Looking at the Infamous Hello, World! Program 46


Dealing with Keywords 49


Working with Statements 51


Working with Blocks 53


Creating Identifiers 55


Crafting Comments 55


Introducing Object-Oriented Programming 57


Importing Java API Classes 63


Chapter 2: Working with Variables and Data Types 65


Declaring Variables 66


Initializing Variables 70


Using Final Variables (Constants) 72


Working with Primitive Data Types 73


Working with Strings 82


Converting and Casting Numeric Data 85


Thinking Inside the Box 87


Understanding Scope 87


Shadowing Variables 89


Printing Data with System.out 90


Getting Input with the Scanner Class 92


Getting Input with the JOptionPane Class 96


Using enum to Create Your Own Data Types 97


Chapter 3: Working with Numbers and Expressions 99


Working with Arithmetic Operators 99


Dividing Integers 102


Combining Operators 104


Using the Unary Plus and Minus Operators 105


Using Increment and Decrement Operators 106


Using the Assignment Operator 108


Using Compound Assignment Operators 110


Using the Math Class 111


Formatting Numbers 121


Recognizing Weird Things about Java Math 124


Chapter 4: Making Choices 129


Using Simple Boolean Expressions 130


Using if Statements 132


Using Mr Spock’s Favorite Operators (Logical Ones, of Course) 141


Using the Conditional Operator 148


Comparing Strings 149


Chapter 5: Going Around in Circles (Or, Using Loops) 151


Using Your Basic while Loop 152


Breaking Out of a Loop 154


Looping Forever 154


Using the continue Statement 157


Running do-while Loops 159


Validating Input from the User 161


Using the Famous for Loop 163


Nesting Your Loops 173


Chapter 6: Pulling a Switcheroo 179


Battling else-if Monstrosities 179


Using the switch Statement 183


Creating Character Cases 186


Intentionally Leaving Out a Break Statement 188


Switching with Strings 191


Chapter 7: Adding Some Methods to Your Madness 193


The Joy of Methods 194


The Basics of Making Methods 195


Methods That Return Values 199


Methods That Take Parameters 206


Chapter 8: Handling Exceptions 213


Understanding Exceptions 214


Catching Exceptions 216


Handling Exceptions with a Preemptive Strike 220


Catching All Exceptions at Once 221


Displaying the Exception Message 223


Using a finally Block 223


Handling Checked Exceptions 226


Throwing Your Own Exceptions 231


Catching Multiple Exceptions 232


Book 3: Object-Oriented Programming 233


Chapter 1: Understanding Object-Oriented Programming 235


What Is Object-Oriented Programming? 235


Understanding Objects 237


Understanding the Life Cycle of an Object 240


Working with Related Classes 241


Designing a Program with Objects 243


Diagramming Classes with UML 244


Chapter 2: Making Your Own Classes 249


Declaring a Class 249


Working with Members 253


Using Getters and Setters 255


Overloading Methods 257


Creating Constructors 259


Finding More Uses for the this Keyword 263


Using Initializers 265


Chapter 3: Working with Statics 267


Understanding Static Fields and Methods 267


Working with Static Fields 269


Using Static Methods 269


Counting Instances 270


Preventing Instances 273


Using Static Initializers 274


Chapter 4: Using Subclasses and Inheritance 277


Introducing Inheritance 277


Creating Subclasses 281


Overriding Methods 283


Protecting Your Members 284


Using this and super in Your Subclasses 284


Understanding Inheritance and Constructors 286


Using final 287


Casting Up and Down 289


Determining an Object’s Type 290


Poly What? 292


Creating Custom Exceptions 294


Chapter 5: Using Abstract Classes and Interfaces 299


Using Abstract Classes 299


Using Interfaces 302


More Things You Can Do with Interfaces 306


Using Default Methods 311


Chapter 6: Using the Object and Class Classes 315


The Mother of All Classes: Object 316


The toString Method 319


The equals Method 322


The clone Method 328


The Class Class 338


Chapter 7: Using Inner Classes, Anonymous Classes, and Lambda Expressions 341


Declaring Inner Classes 342


Using Static Inner Classes 345


Using Anonymous Inner Classes 347


Using Lambda Expressions 351


Chapter 8: Working with Packages and the New Java Module System 353


Working with Packages 354


Putting Your Classes in a JAR File 358


Using JavaDoc to Document Your Classes 363


Using the Java Module System 368


Book 4: Strings, Arrays, and Collections 373


Chapter 1: Working with Strings 375


Reviewing Strings 376


Using the String Class 378


Using the StringBuilder and StringBuffer Classes 387


Using the CharSequence Interface 391


Chapter 2: Using Arrays 393


Understanding Arrays 393


Creating Arrays 394


Initializing an Array 395


Using for Loops with Arrays 396


Solving Homework Problems with Arrays 397


Using the Enhanced for Loop 400


Using Arrays with Methods 401


Using Two-Dimensional Arrays 401


Working with a Fun but Complicated Example: A Chessboard 408


Using the Arrays Class 416


Chapter 3: Using the ArrayList Class 423


Understanding the ArrayList Class 424


Creating an ArrayList Object 427


Adding Elements 428


Accessing Elements 429


Printing an ArrayList 430


Using an Iterator 430


Updating Elements 432


Deleting Elements 434


Chapter 4: Using the LinkedList Class 437


Understanding the LinkedList Class 438


Creating a LinkedList 442


Adding Items to a LinkedList 443


Retrieving Items from a LinkedList 445


Updating LinkedList Items 446


Removing LinkedList Items 447


Chapter 5: Creating Generic Collection Classes 449


Why Generics? 450


Creating a Generic Class 451


A Generic Stack Class 453


Using Wildcard-Type Parameters 457


A Generic Queue Class 458


Using the Diamond Operator 462


Chapter 6: Using Bulk Data Operations with Collections 463


Looking At a Basic Bulk Data Operation 464


Looking Closer at the Stream Interface 467


Using Parallel Streams 470


Book 5: Programming Techniques 473


Chapter 1: Programming Threads 475


Understanding Threads 476


Creating a Thread 477


Implementing the Runnable Interface 480


Creating Threads That Work Together 485


Using an Executor 489


Synchronizing Methods 491


Creating a Lock 496


Coping with Threadus Interruptus 497


Chapter 2: Using Regular Expressions 505


Creating a Program for Experimenting with Regular Expressions 506


Performing Basic Character Matching 509


Using Regular Expressions in Java Programs 519


Chapter 3: Using Recursion 523


Calculating the Classic Factorial Example 523


Displaying Directories 526


Writing Your Own Sorting Routine 530


Chapter 4: Working with Dates and Times 539


Pondering How Time is Represented 540


Picking the Right Date and Time Class for Your Application 541


Using the now Method to Create a Date-Time Object 542


Using the parse Method to Create a Date-Time Object 544


Using the of Method to Create a Date-Time Object 545


Looking Closer at the LocalDate Class 548


Extracting Information About a Date 550


Comparing Dates 551


Calculating with Dates 552


Formatting Dates 554


Looking at a Fun Birthday Calculator 556


Book 6: JavaFX 561


Chapter 1: Hello, JavaFX! 563


Perusing the Possibilities of JavaFX 564


Looking at a Simple JavaFX Program 566


Importing JavaFX Packages 567


Extending the Application Class 568


Launching the Application 569


Overriding the start Method 570


Creating a Button 572


Handling an Action Event 573


Creating a Layout Pane 574


Making a Scene 576


Setting the Stage 576


Examining the Click Counter Program 577


Chapter 2: Handling Events 583


Examining Events 584


Handling Events 585


Implementing the EventHandler Interface 587


Handling Events with Inner Classes 591


Handling Events with Anonymous Inner Classes 593


Using Lambda Expressions to Handle Events 596


Chapter 3: Setting the Stage and Scene Layout 603


Examining the Stage Class 604


Examining the Scene Class 607


Switching Scenes 609


Creating an Alert Box 613


Exit, Stage Right 618


Chapter 4: Using Layout Panes to Arrange Your Scenes 625


Working with Layout Panes 626


Using the HBox Layout 628


Spacing Things Out 630


Adding Space with Margins 632


Adding Space by Growing Nodes 633


Using the VBox Layout 635


Aligning Nodes in a Layout Pane 637


Making Nodes the Same Width 638


Using the Flow Layout 639


Using the Border Layout 643


Using the GridPane Layout 645


Chapter 5: Getting Input from the User 659


Using Text Fields 660


Validating Numeric Data 667


Using Check Boxes 668


Using Radio Buttons 671


Looking at a Pizza Order Application 673


Chapter 6: Choosing from a List 681


Using Choice Boxes 681


Working with Observable Lists 685


Listening for Selection Changes 688


Using Combo Boxes 690


Using List Views 694


Using Tree Views 696


Book 7: Web Programming 707


Chapter 1: Using Java Web Start 709


Looking at a Simple JavaFX Program 709


Understanding Java Web Start 712


Creating a JNLP File 713


Creating an HTML File to Launch a Java Application 715


Uploading the Java Web Start Files to Your Web Server 716


Launching the ClickMe Application Using Java Web Start 717


Creating an Exception to Allow Java Web Start Applications to Run 718


Chapter 2: Creating Servlets 721


Understanding Servlets 721


Using Tomcat 723


Creating a Simple Servlet 726


Running a Servlet 730


Improving the HelloWorld Servlet 730


Getting Input from the User 732


Using Classes in a Servlet 735


Chapter 3: Using JavaServer Pages 741


Understanding JavaServer Pages 742


Using Page Directives 743


Using Expressions 744


Using Scriptlets 746


Using Declarations 749


Using Classes 751


Chapter 4: Using JavaBeans 757


Getting to Know JavaBeans 757


Looking Over a Sample Bean 759


Using Beans with JSP Pages 761


Scoping Your Beans 767


Book 8: Files and Databases 775


Chapter 1: Working with Files 777


Using the File Class 777


Using Command-Line Parameters 784


Choosing Files in a Swing Application 785


Using Path Objects 792


Using a File Visitor to Walk a File Tree 795


Chapter 2: Working with File Streams 799


Understanding Streams 800


Reading Character Streams 801


Writing Character Streams 807


Reading Binary Streams 813


Writing Binary Streams 820


Chapter 3: Database for $100, Please 827


Defining a Relational Database 828


Understanding (and Pronouncing) SQL 828


Introducing SQL Statements 829


Creating a SQL Database 829


Querying a Database 832


Updating and Deleting Rows 839


Chapter 4: Using JDBC to Connect to a Database 845


Setting Up a Driver 845


Connecting to a Database 846


Querying a Database 848


Updating SQL Data 855


Using an Updatable RowSet Object 856


Chapter 5: Working with XML 861


Defining XML 861


Using a DTD 865


Processing XML in Two Ways: DOM and SAX 868


Reading a DOM Document 869


Reading DOM Nodes 872


Putting It All Together: A Program That Lists Movies 877


Index 881