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Core Java® for the Impatient

Book Description

The release of Java SE 8 introduced significant enhancements that impact the Core Java technologies and APIs at the heart of the Java platform. Many old Java idioms are no longer required and new features like lambda expressions will increase programmer productivity, but navigating these changes can be challenging.

Core Java® for the Impatient is a complete but concise guide to Java SE 8. Written by Cay Horstmann—the author of Java SE 8 for the Really Impatient and Core Java™, the classic, two-volume introduction to the Java language—this indispensable new tutorial offers a faster, easier pathway for learning the language and libraries. Given the size of the language and the scope of the new features introduced in Java SE 8, there’s plenty of material to cover, but it’s presented in small chunks organized for quick access and easy understanding.

If you’re an experienced programmer, Horstmann’s practical insights and sample code will help you quickly take advantage of lambda expressions (closures), streams, and other Java language and platform improvements. Horstmann covers everything developers need to know about modern Java, including 

  • Crisp and effective coverage of lambda expressions, enabling you to express actions with a concise syntax

  • A thorough introduction to the new streams API, which makes working with data far more flexible and efficient

  • A treatment of concurrent programming that encourages you to design your programs in terms of cooperating tasks instead of low-level threads and locks

  • Up-to-date coverage of new libraries like Date and Time

  • Other new features that will be especially valuable for server-side or mobile programmers 

  • Whether you are just getting started with modern Java or are an experienced developer, this guide will be invaluable for anyone who wants to write tomorrow’s most robust, efficient, and secure Java code.

    Table of Contents

    1. About This eBook
    2. Title Page
    3. Copyright Page
    4. Dedication Page
    5. Contents
    6. Preface
    7. Acknowledgments
    8. About the Author
    9. Chapter 1. Fundamental Programming Structures
      1. 1.1 Our First Program
        1. 1.1.1 Dissecting the “Hello, World” Program
        2. 1.1.2 Compiling and Running a Java Program
        3. 1.1.3 Method Calls
      2. 1.2 Primitive Types
        1. 1.2.1 Integer Types
        2. 1.2.2 Floating-Point Types
        3. 1.2.3 The char Type
        4. 1.2.4 The boolean Type
      3. 1.3 Variables
        1. 1.3.1 Variable Declarations
        2. 1.3.2 Names
        3. 1.3.3 Initialization
        4. 1.3.4 Constants
      4. 1.4 Arithmetic Operations
        1. 1.4.1 Assignment
        2. 1.4.2 Basic Arithmetic
        3. 1.4.3 Mathematical Methods
        4. 1.4.4 Number Type Conversions
        5. 1.4.5 Relational and Logical Operators
        6. 1.4.6 Big Numbers
      5. 1.5 Strings
        1. 1.5.1 Concatenation
        2. 1.5.2 Substrings
        3. 1.5.3 String Comparison
        4. 1.5.4 Converting Between Numbers and Strings
        5. 1.5.5 The String API
        6. 1.5.6 Code Points and Code Units
      6. 1.6 Input and Output
        1. 1.6.1 Reading Input
        2. 1.6.2 Formatted Output
      7. 1.7 Control Flow
        1. 1.7.1 Branches
        2. 1.7.2 Loops
        3. 1.7.3 Breaking and Continuing
        4. 1.7.4 Local Variable Scope
      8. 1.8 Arrays and Array Lists
        1. 1.8.1 Working with Arrays
        2. 1.8.2 Array Construction
        3. 1.8.3 Array Lists
        4. 1.8.4 Wrapper Classes for Primitive Types
        5. 1.8.5 The Enhanced for Loop
        6. 1.8.6 Copying Arrays and Array Lists
        7. 1.8.7 Array Algorithms
        8. 1.8.8 Command-Line Arguments
        9. 1.8.9 Multidimensional Arrays
      9. 1.9 Functional Decomposition
        1. 1.9.1 Declaring and Calling Static Methods
        2. 1.9.2 Array Parameters and Return Values
        3. 1.9.3 Variable Arguments
      10. Exercises
    10. Chapter 2. Object-Oriented Programming
      1. 2.1 Working with Objects
        1. 2.1.1 Accessor and Mutator Methods
        2. 2.1.2 Object References
      2. 2.2 Implementing Classes
        1. 2.2.1 Instance Variables
        2. 2.2.2 Method Headers
        3. 2.2.3 Method Bodies
        4. 2.2.4 Instance Method Invocations
        5. 2.2.5 The this Reference
        6. 2.2.6 Call by Value
      3. 2.3 Object Construction
        1. 2.3.1 Implementing Constructors
        2. 2.3.2 Overloading
        3. 2.3.3 Calling One Constructor from Another
        4. 2.3.4 Default Initialization
        5. 2.3.5 Instance Variable Initialization
        6. 2.3.6 Final Instance Variables
        7. 2.3.7 The Constructor with No Arguments
      4. 2.4 Static Variables and Methods
        1. 2.4.1 Static Variables
        2. 2.4.2 Static Constants
        3. 2.4.3 Static Initialization Blocks
        4. 2.4.4 Static Methods
        5. 2.4.5 Factory Methods
      5. 2.5 Packages
        1. 2.5.1 Package Declarations
        2. 2.5.2 The Class Path
        3. 2.5.3 Package Scope
        4. 2.5.4 Importing Classes
        5. 2.5.5 Static Imports
      6. 2.6 Nested Classes
        1. 2.6.1 Static Nested Classes
        2. 2.6.2 Inner Classes
        3. 2.6.3 Special Syntax Rules for Inner Classes
      7. 2.7 Documentation Comments
        1. 2.7.1 Comment Insertion
        2. 2.7.2 Class Comments
        3. 2.7.3 Method Comments
        4. 2.7.4 Variable Comments
        5. 2.7.5 General Comments
        6. 2.7.6 Links
        7. 2.7.7 Package and Overview Comments
        8. 2.7.8 Comment Extraction
      8. Exercises
    11. Chapter 3. Interfaces and Lambda Expressions
      1. 3.1 Interfaces
        1. 3.1.1 Declaring an Interface
        2. 3.1.2 Implementing an Interface
        3. 3.1.3 Converting to an Interface Type
        4. 3.1.4 Casts and the instanceof Operator
        5. 3.1.5 Extending Interfaces
        6. 3.1.6 Implementing Multiple Interfaces
        7. 3.1.7 Constants
      2. 3.2 Static and Default Methods
        1. 3.2.1 Static Methods
        2. 3.2.2 Default Methods
        3. 3.2.3 Resolving Default Method Conflicts
      3. 3.3 Examples of Interfaces
        1. 3.3.1 The Comparable Interface
        2. 3.3.2 The Comparator Interface
        3. 3.3.3 The Runnable Interface
        4. 3.3.4 User Interface Callbacks
      4. 3.4 Lambda Expressions
        1. 3.4.1 The Syntax of Lambda Expressions
        2. 3.4.2 Functional Interfaces
      5. 3.5 Method and Constructor References
        1. 3.5.1 Method References
        2. 3.5.2 Constructor References
      6. 3.6 Processing Lambda Expressions
        1. 3.6.1 Implementing Deferred Execution
        2. 3.6.2 Choosing a Functional Interface
        3. 3.6.3 Implementing Your Own Functional Interfaces
      7. 3.7 Lambda Expressions and Variable Scope
        1. 3.7.1 Scope of a Lambda Expression
        2. 3.7.2 Accessing Variables from the Enclosing Scope
      8. 3.8 Higher-Order Functions
        1. 3.8.1 Methods that Return Functions
        2. 3.8.2 Methods That Modify Functions
        3. 3.8.3 Comparator Methods
      9. 3.9 Local Inner Classes
        1. 3.9.1 Local Classes
        2. 3.9.2 Anonymous Classes
      10. Exercises
    12. Chapter 4. Inheritance and Reflection
      1. 4.1 Extending a Class
        1. 4.1.1 Super- and Subclasses
        2. 4.1.2 Defining and Inheriting Subclass Methods
        3. 4.1.3 Method Overriding
        4. 4.1.4 Subclass Construction
        5. 4.1.5 Superclass Assignments
        6. 4.1.6 Casts
        7. 4.1.7 Final Methods and Classes
        8. 4.1.8 Abstract Methods and Classes
        9. 4.1.9 Protected Access
        10. 4.1.10 Anonymous Subclasses
        11. 4.1.11 Inheritance and Default Methods
        12. 4.1.12 Method Expressions with super
      2. 4.2 Object: The Cosmic Superclass
        1. 4.2.1 The toString Method
        2. 4.2.2 The equals Method
        3. 4.2.3 The hashCode Method
        4. 4.2.4 Cloning Objects
      3. 4.3 Enumerations
        1. 4.3.1 Methods of Enumerations
        2. 4.3.2 Constructors, Methods, and Fields
        3. 4.3.3 Bodies of Instances
        4. 4.3.4 Static Members
        5. 4.3.5 Switching on an Enumeration
      4. 4.4 Runtime Type Information and Resources
        1. 4.4.1 The Class Class
        2. 4.4.2 Loading Resources
        3. 4.4.3 Class Loaders
        4. 4.4.4 The Context Class Loader
        5. 4.4.5 Service Loaders
      5. 4.5 Reflection
        1. 4.5.1 Enumerating Class Members
        2. 4.5.2 Inspecting Objects
        3. 4.5.3 Invoking Methods
        4. 4.5.4 Constructing Objects
        5. 4.5.5 JavaBeans
        6. 4.5.6 Working with Arrays
        7. 4.5.7 Proxies
      6. Exercises
    13. Chapter 5. Exceptions, Assertions, and Logging
      1. 5.1 Exception Handling
        1. 5.1.1 Throwing Exceptions
        2. 5.1.2 The Exception Hierarchy
        3. 5.1.3 Declaring Checked Exceptions
        4. 5.1.4 Catching Exceptions
        5. 5.1.5 The Try-with-Resources Statement
        6. 5.1.6 The finally Clause
        7. 5.1.7 Rethrowing and Chaining Exceptions
        8. 5.1.8 The Stack Trace
        9. 5.1.9 The Objects.requireNonNull Method
      2. 5.2 Assertions
        1. 5.2.1 Using Assertions
        2. 5.2.2 Enabling and Disabling Assertions
      3. 5.3 Logging
        1. 5.3.1 Using Loggers
        2. 5.3.2 Loggers
        3. 5.3.3 Logging Levels
        4. 5.3.4 Other Logging Methods
        5. 5.3.5 Logging Configuration
        6. 5.3.6 Log Handlers
        7. 5.3.7 Filters and Formatters
      4. Exercises
    14. Chapter 6. Generic Programming
      1. 6.1 Generic Classes
      2. 6.2 Generic Methods
      3. 6.3 Type Bounds
      4. 6.4 Type Variance and Wildcards
        1. 6.4.1 Subtype Wildcards
        2. 6.4.2 Supertype Wildcards
        3. 6.4.3 Wildcards with Type Variables
        4. 6.4.4 Unbounded Wildcards
        5. 6.4.5 Wildcard Capture
      5. 6.5 Generics in the Java Virtual Machine
        1. 6.5.1 Type Erasure
        2. 6.5.2 Cast Insertion
        3. 6.5.3 Bridge Methods
      6. 6.6 Restrictions on Generics
        1. 6.6.1 No Primitive Type Arguments
        2. 6.6.2 At Runtime, All Types Are Raw
        3. 6.6.3 You Cannot Instantiate Type Variables
        4. 6.6.4 You Cannot Construct Arrays of Parameterized Types
        5. 6.6.5 Class Type Variables Are Not Valid in Static Contexts
        6. 6.6.6 Methods May Not Clash after Erasure
        7. 6.6.7 Exceptions and Generics
      7. 6.7 Reflection and Generics
        1. 6.7.1 The Class<T> Class
        2. 6.7.2 Generic Type Information in the Virtual Machine
      8. Exercises
    15. Chapter 7. Collections
      1. 7.1 An Overview of the Collections Framework
      2. 7.2 Iterators
      3. 7.3 Sets
      4. 7.4 Maps
      5. 7.5 Other Collections
        1. 7.5.1 Properties
        2. 7.5.2 Bit Sets
        3. 7.5.3 Enumeration Sets and Maps
        4. 7.5.4 Stacks, Queues, Deques, and Priority Queues
        5. 7.5.5 Weak Hash Maps
      6. 7.6 Views
        1. 7.6.1 Ranges
        2. 7.6.2 Empty and Singleton Views
        3. 7.6.3 Unmodifiable Views
      7. Exercises
    16. Chapter 8. Streams
      1. 8.1 From Iterating to Stream Operations
      2. 8.2 Stream Creation
      3. 8.3 The filter, map, and flatMap Methods
      4. 8.4 Extracting Substreams and Combining Streams
      5. 8.5 Other Stream Transformations
      6. 8.6 Simple Reductions
      7. 8.7 The Optional Type
        1. 8.7.1 How to Work with Optional Values
        2. 8.7.2 How Not to Work with Optional Values
        3. 8.7.3 Creating Optional Values
        4. 8.7.4 Composing Optional Value Functions with flatMap
      8. 8.8 Collecting Results
      9. 8.9 Collecting into Maps
      10. 8.10 Grouping and Partitioning
      11. 8.11 Downstream Collectors
      12. 8.12 Reduction Operations
      13. 8.13 Primitive Type Streams
      14. 8.14 Parallel Streams
      15. Exercises
    17. Chapter 9. Processing Input and Output
      1. 9.1 Input/Output Streams, Readers, and Writers
        1. 9.1.1 Obtaining Streams
        2. 9.1.2 Reading Bytes
        3. 9.1.3 Writing Bytes
        4. 9.1.4 Character Encodings
        5. 9.1.5 Text Input
        6. 9.1.6 Text Output
        7. 9.1.7 Reading and Writing Binary Data
        8. 9.1.8 Random-Access Files
        9. 9.1.9 Memory-Mapped Files
        10. 9.1.10 File Locking
      2. 9.2 Paths, Files, and Directories
        1. 9.2.1 Paths
        2. 9.2.2 Creating Files and Directories
        3. 9.2.3 Copying, Moving, and Deleting Files
        4. 9.2.4 Visiting Directory Entries
        5. 9.2.5 ZIP File Systems
      3. 9.3 URL Connections
      4. 9.4 Regular Expressions
        1. 9.4.1 The Regular Expression Syntax
        2. 9.4.2 Finding One or All Matches
        3. 9.4.3 Groups
        4. 9.4.4 Removing or Replacing Matches
        5. 9.4.5 Flags
      5. 9.5 Serialization
        1. 9.5.1 The Serializable Interface
        2. 9.5.2 Transient Instance Variables
        3. 9.5.3 The readObject and writeObject Methods
        4. 9.5.4 The readResolve and writeReplace Methods
        5. 9.5.5 Versioning
      6. Exercises
    18. Chapter 10. Concurrent Programming
      1. 10.1 Concurrent Tasks
        1. 10.1.1 Running Tasks
        2. 10.1.2 Futures and Executor Services
      2. 10.2 Thread Safety
        1. 10.2.1 Visibility
        2. 10.2.2 Race Conditions
        3. 10.2.3 Strategies for Safe Concurrency
        4. 10.2.4 Immutable Classes
      3. 10.3 Parallel Algorithms
        1. 10.3.1 Parallel Streams
        2. 10.3.2 Parallel Array Operations
      4. 10.4 Threadsafe Data Structures
        1. 10.4.1 Concurrent Hash Maps
        2. 10.4.2 Blocking Queues
        3. 10.4.3 Other Threadsafe Data Structures
      5. 10.5 Atomic Values
      6. 10.6 Locks
        1. 10.6.1 Reentrant Locks
        2. 10.6.2 The synchronized Keyword
        3. 10.6.3 Waiting on Conditions
      7. 10.7 Threads
        1. 10.7.1 Starting a Thread
        2. 10.7.2 Thread Interruption
        3. 10.7.3 Thread-Local Variables
        4. 10.7.4 Miscellaneous Thread Properties
      8. 10.8 Asynchronous Computations
        1. 10.8.1 Long-Running Tasks in User Interface Callbacks
        2. 10.8.2 Completable Futures
      9. 10.9 Processes
        1. 10.9.1 Building a Process
        2. 10.9.2 Running a Process
      10. Exercises
    19. Chapter 11. Annotations
      1. 11.1 Using Annotations
        1. 11.1.1 Annotation Elements
        2. 11.1.2 Multiple and Repeated Annotations
        3. 11.1.3 Annotating Declarations
        4. 11.1.4 Annotating Type Uses
        5. 11.1.5 Making Receivers Explicit
      2. 11.2 Defining Annotations
      3. 11.3 Standard Annotations
        1. 11.3.1 Annotations for Compilation
        2. 11.3.2 Annotations for Managing Resources
        3. 11.3.3 Meta-Annotations
      4. 11.4 Processing Annotations at Runtime
      5. 11.5 Source-Level Annotation Processing
        1. 11.5.1 Annotation Processors
        2. 11.5.2 The Language Model API
        3. 11.5.3 Using Annotations to Generate Source Code
      6. Exercises
    20. Chapter 12. The Date and Time API
      1. 12.1 The Time Line
      2. 12.2 Local Dates
      3. 12.3 Date Adjusters
      4. 12.4 Local Time
      5. 12.5 Zoned Time
      6. 12.6 Formatting and Parsing
      7. 12.7 Interoperating with Legacy Code
      8. Exercises
    21. Chapter 13. Internationalization
      1. 13.1 Locales
        1. 13.1.1 Specifying a Locale
        2. 13.1.2 The Default Locale
        3. 13.1.3 Display Names
      2. 13.2 Number Formats
      3. 13.3 Currencies
      4. 13.4 Date and Time Formatting
      5. 13.5 Collation and Normalization
      6. 13.6 Message Formatting
      7. 13.7 Resource Bundles
        1. 13.7.1 Organizing Resource Bundles
        2. 13.7.2 Bundle Classes
      8. 13.8 Character Encodings
      9. 13.9 Preferences
      10. Exercises
    22. Chapter 14. Compiling and Scripting
      1. 14.1 The Compiler API
        1. 14.1.1 Invoking the Compiler
        2. 14.1.2 Launching a Compilation Task
        3. 14.1.3 Reading Source Files from Memory
        4. 14.1.4 Writing Byte Codes to Memory
        5. 14.1.5 Capturing Diagnostics
      2. 14.2 The Scripting API
        1. 14.2.1 Getting a Scripting Engine
        2. 14.2.2 Bindings
        3. 14.2.3 Redirecting Input and Output
        4. 14.2.4 Calling Scripting Functions and Methods
        5. 14.2.5 Compiling a Script
      3. 14.3 The Nashorn Scripting Engine
        1. 14.3.1 Running Nashorn from the Command Line
        2. 14.3.2 Invoking Getters, Setters, and Overloaded Methods
        3. 14.3.3 Constructing Java Objects
        4. 14.3.4 Strings in JavaScript and Java
        5. 14.3.5 Numbers
        6. 14.3.6 Working with Arrays
        7. 14.3.7 Lists and Maps
        8. 14.3.8 Lambdas
        9. 14.3.9 Extending Java Classes and Implementing Java Interfaces
        10. 14.3.10 Exceptions
      4. 14.4 Shell Scripting with Nashorn
        1. 14.4.1 Executing Shell Commands
        2. 14.4.2 String Interpolation
        3. 14.4.3 Script Inputs
      5. Exercises
    23. Index
    24. Code Snippets