Interest in the Scala programming language continues to grow for many reasons. Scala embraces the functional programming style without abandoning the object-oriented paradigm, and it allows you to write programs more concisely than in Java. Because Scala runs on the JVM, it can access any Java library and is interoperable with familiar Java frameworks. Scala also makes it easier to leverage the full power of concurrency.
Written for experienced Java, C++, or C# programmers who are new to Scala or functional programming, Scala for the Impatient, Second Edition, introduces the key Scala concepts and techniques you need in order to be productive quickly. It is the perfect introduction to the language, particularly for impatient readers who want to learn the fundamentals of Scala so they can start coding quickly. It doesn't attempt to exhaustively list all the features of the language or make you suffer through long and contrived examples. Instead, carefully crafted examples and hands-on activities guide you through well-defined stages of competency, from basic to expert.
This revised edition has been thoroughly updated for Scala 2.12 and reflects current Scala usage. It includes added coverage of recent Scala features, including string interpolation, dynamic invocation, implicit classes, and futures. Scala is a big language, but you can use it effectively without knowing all of its details intimately. This title provides precisely the information that you need to get started in compact, easy-to-understand chunks.
Get started quickly with Scala's interpreter, syntax, tools, and unique idioms
Master core language features: functions, arrays, maps, tuples, packages, imports, exception handling, and more
Become familiar with object-oriented programming in Scala: classes, inheritance, and traits
Use Scala for real-world programming tasks: working with files, regular expressions, and XML
Work with higher-order functions and the powerful Scala collections library
Leverage Scala's powerful pattern matching and case classes
Create concurrent programs with Scala futures
Implement domain-specific languages
Understand the Scala type system
Apply advanced "power tools," such as annotations, implicits, and type classes
Register your product at informit.com/register for convenient access to downloads, updates, and corrections as they become available.
Auflage
Sprache
Verlagsort
Verlagsgruppe
Zielgruppe
Editions-Typ
Produkt-Hinweis
Broschur/Paperback
Klebebindung
Maße
Höhe: 231 mm
Breite: 177 mm
Dicke: 25 mm
Gewicht
ISBN-13
978-0-13-454056-6 (9780134540566)
Schweitzer Klassifikation
Cay S. Horstmann is principal author of Core Java (R), Volumes I & II, Tenth Edition (Prentice Hall), as well as a dozen other books for professional programmers and computer science students. He is a professor of computer science at San Jose State University and a Java Champion.
Foreword to the First Edition xvii
Preface xix
About the Author xxi
Chapter 1: The Basics 1
1.1 The Scala Interpreter 1
1.2 Declaring Values and Variables 4
1.3 Commonly Used Types 5
1.4 Arithmetic and Operator Overloading 6
1.5 More about Calling Methods 8
1.6 The apply Method 9
1.7 Scaladoc 10
Exercises 15
Chapter 2: Control Structures and Functions 17
2.1 Conditional Expressions 18
2.2 Statement Termination 19
2.3 Block Expressions and Assignments 20
2.4 Input and Output 21
2.5 Loops 22
2.6 Advanced for Loops 24
2.7 Functions 25
2.8 Default and Named Arguments 26
2.9 Variable Arguments 26
2.10 Procedures 28
2.11 Lazy Values 28
2.12 Exceptions 29
Exercises 31
Chapter 3: Working with Arrays 35
3.1 Fixed-Length Arrays 35
3.2 Variable-Length Arrays: Array Buffers 36
3.3 Traversing Arrays and Array Buffers 37
3.4 Transforming Arrays 38
3.5 Common Algorithms 40
3.6 Deciphering Scaladoc 41
3.7 Multidimensional Arrays 42
3.8 Interoperating with Java 43
Exercises 44
Chapter 4: Maps and Tuples 47
4.1 Constructing a Map 48
4.2 Accessing Map Values 48
4.3 Updating Map Values 49
4.4 Iterating over Maps 50
4.5 Sorted Maps 50
4.6 Interoperating with Java 50
4.7 Tuples 51
4.8 Zipping 52
Exercises 52
Chapter 5: Classes 55
5.1 Simple Classes and Parameterless Methods 55
5.2 Properties with Getters and Setters 56
5.3 Properties with Only Getters 59
5.4 Object-Private Fields 60
5.5 Bean Properties 61
5.6 Auxiliary Constructors 62
5.7 The Primary Constructor 63
5.8 Nested Classes 66
Exercises 68
Chapter 6: Objects 71
6.1 Singletons 71
6.2 Companion Objects 72
6.3 Objects Extending a Class or Trait 73
6.4 The apply Method 73
6.5 Application Objects 74
6.6 Enumerations 75
Exercises 77
Chapter 7: Packages and Imports 79
7.1 Packages 80
7.2 Scope Rules 81
7.3 Chained Package Clauses 83
7.4 Top-of-File Notation 83
7.5 Package Objects 83
7.6 Package Visibility 84
7.7 Imports 85
7.8 Imports Can Be Anywhere 85
7.9 Renaming and Hiding Members 86
7.10 Implicit Imports 86
Exercises 87
Chapter 8: Inheritance 91
8.1 Extending a Class 91
8.2 Overriding Methods 92
8.3 Type Checks and Casts 93
8.4 Protected Fields and Methods 94
8.5 Superclass Construction 94
8.6 Overriding Fields 95
8.7 Anonymous Subclasses 97
8.8 Abstract Classes 97
8.9 Abstract Fields 97
8.10 Construction Order and Early Definitions 98
8.11 The Scala Inheritance Hierarchy 100
8.12 Object Equality 102
8.13 Value Classes 103
Exercises 105
Chapter 9: Files and Regular Expressions 109
9.1 Reading Lines 109
9.2 Reading Characters 110
9.3 Reading Tokens and Numbers 111
9.4 Reading from URLs and Other Sources 111
9.5 Reading Binary Files 112
9.6 Writing Text Files 112
9.7 Visiting Directories 112
9.8 Serialization 113
9.9 Process Control 114
9.10 Regular Expressions 116
9.11 Regular Expression Groups 117
Exercises 118
Chapter 10: Traits 121
10.1 Why No Multiple Inheritance? 121
10.2 Traits as Interfaces 123
10.3 Traits with Concrete Implementations 124
10.4 Objects with Traits 125
10.5 Layered Traits 125
10.6 Overriding Abstract Methods in Traits 127
10.7 Traits for Rich Interfaces 127
10.8 Concrete Fields in Traits 128
10.9 Abstract Fields in Traits 130
10.10 Trait Construction Order 130
10.11 Initializing Trait Fields 132
10.12 Traits Extending Classes 133
10.13 Self Types 134
10.14 What Happens under the Hood 135
Exercises 137
Chapter 11: Operators 141
11.1 Identifiers 142
11.2 Infix Operators 143
11.3 Unary Operators 143
11.4 Assignment Operators 144
11.5 Precedence 144
11.6 Associativity 145
11.7 The apply and update Methods 146
11.8 Extractors 147
11.9 Extractors with One or No Arguments 149
11.10 The unapplySeq Method 149
11.11 Dynamic Invocation 150
Exercises 153
Chapter 12: Higher-Order Functions 157
12.1 Functions as Values 157
12.2 Anonymous Functions 159
12.3 Functions with Function Parameters 160
12.4 Parameter Inference 160
12.5 Useful Higher-Order Functions 161
12.6 Closures 162
12.7 SAM Conversions 163
12.8 Currying 164
12.9 Control Abstractions 166
12.10 The return Expression 167
Exercises 168
Chapter 13: Collections 171
13.1 The Main Collections Traits 172
13.2 Mutable and Immutable Collections 173
13.3 Sequences 174
13.4 Lists 175
13.5 Sets 177
13.6 Operators for Adding or Removing Elements 178
13.7 Common Methods 180
13.8 Mapping a Function 182
13.9 Reducing, Folding, and Scanning 184
13.10 Zipping 187
13.11 Iterators 188
13.12 Streams 189
13.13 Lazy Views 190
13.14 Interoperability with Java Collections 191
13.15 Parallel Collections 193
Exercises 194
Chapter 14: Pattern Matching and Case Classes 197
14.1 A Better Switch 198
14.2 Guards 199
14.3 Variables in Patterns 199
14.4 Type Patterns 200
14.5 Matching Arrays, Lists, and Tuples 201
14.6 Extractors 202
14.7 Patterns in Variable Declarations 203
14.8 Patterns in for Expressions 204
14.9 Case Classes 205
14.10 The copy Method and Named Parameters 205
14.11 Infix Notation in case Clauses 206
14.12 Matching Nested Structures 207
14.13 Are Case Classes Evil? 208
14.14 Sealed Classes 209
14.15 Simulating Enumerations 209
14.16 The Option Type 210
14.17 Partial Functions 211
Exercises 212
Chapter 15: Annotations 215
15.1 What Are Annotations? 216
15.2 What Can Be Annotated? 216
15.3 Annotation Arguments 217
15.4 Annotation Implementations 218
15.5 Annotations for Java Features 219
15.6 Annotations for Optimizations 222
15.7 Annotations for Errors and Warnings 226
Exercises 227
Chapter 16: XML Processing 229
16.1 XML Literals 230
16.2 XML Nodes 230
16.3 Element Attributes 232
16.4 Embedded Expressions 233
16.5 Expressions in Attributes 234
16.6 Uncommon Node Types 235
16.7 XPath-like Expressions 235
16.8 Pattern Matching 237
16.9 Modifying Elements and Attributes 238
16.10 Transforming XML 239
16.11 Loading and Saving 239
16.12 Namespaces 242
Exercises 243
Chapter 17: Futures 247
17.1 Running Tasks in the Future 248
17.2 Waiting for Results 250
17.3 The Try Class 251
17.4 Callbacks 251
17.5 Composing Future Tasks 252
17.6 Other Future Transformations 255
17.7 Methods in the Future Object 256
17.8 Promises 258
17.9 Execution Contexts 260
Exercises 260
Chapter 18: Type Parameters 265
18.1 Generic Classes 266
18.2 Generic Functions 266
18.3 Bounds for Type Variables 266
18.4 View Bounds 268
18.5 Context Bounds 268
18.6 The ClassTag Context Bound 269
18.7 Multiple Bounds 269
18.8 Type Constraints 269
18.9 Variance 271
18.10 Co- and Contravariant Positions 272
18.11 Objects Can't Be Generic 274
18.12 Wildcards 275
Exercises 275
Chapter 19: Advanced Types 279
19.1 Singleton Types 280
19.2 Type Projections 281
19.3 Paths 282
19.4 Type Aliases 283
19.5 Structural Types 283
19.6 Compound Types 284
19.7 Infix Types 285
19.8 Existential Types 286
19.9 The Scala Type System 287
19.10 Self Types 288
19.11 Dependency Injection 289
19.12 Abstract Types 291
19.13 Family Polymorphism 293
19.14 Higher-Kinded Types 296
Exercises 299
Chapter 20: Parsing 303
20.1 Grammars 304
20.2 Combining Parser Operations 305
20.3 Transforming Parser Results 307
20.4 Discarding Tokens 308
20.5 Generating Parse Trees 309
20.6 Avoiding Left Recursion 310
20.7 More Combinators 311
20.8 Avoiding Backtracking 314
20.9 Packrat Parsers 314
20.10 What Exactly Are Parsers? 315
20.11 Regex Parsers 316
20.12 Token-Based Parsers 317
20.13 Error Handling 319
Exercises 320
Chapter 21: Implicits 323
21.1 Implicit Conversions 324
21.2 Using Implicits for Enriching Existing Classes 324
21.3 Importing Implicits 325
21.4 Rules for Implicit Conversions 326
21.5 Implicit Parameters 328
21.6 Implicit Conversions with Implicit Parameters 329
21.7 Context Bounds 329
21.8 Type Classes 331
21.9 Evidence 333
21.10 The @implicitNotFound Annotation 334
21.11 CanBuildFrom Demystified 334
Exercises 336
Index 338
