Effective Java

Foreword xi
Preface xiii
Acknowledgments xvii

Chapter 1: Introduction 1

Chapter 2: Creating and Destroying Objects 5
Item 1: Consider static factory methods instead of constructors 5
Item 2: Consider a builder when faced with many constructor parameters 10
Item 3: Enforce the singleton property with a private constructor or an enum type 17
Item 4: Enforce noninstantiability with a private constructor 19
Item 5: Prefer dependency injection to hardwiring resources 20
Item 6: Avoid creating unnecessary objects 22
Item 7: Eliminate obsolete object references 26
Item 8: Avoid finalizers and cleaners 29
Item 9: Prefer try-with-resources to try-finally 34

Chapter 3: Methods Common to All Objects 37
Item 10: Obey the general contract when overriding equals 37
Item 11: Always override hashCode when you override equals 50
Item 12: Always override toString 55
Item 13: Override clone judiciously 58
Item 14: Consider implementing Comparable 66

Chapter 4: Classes and Interfaces 73
Item 15: Minimize the accessibility of classes and members 73
Item 16: In public classes, use accessor methods, not public fields 78
Item 17: Minimize mutability 80
Item 18: Favor composition over inheritance 87
Item 19: Design and document for inheritance or else prohibit it 93
Item 20: Prefer interfaces to abstract classes 99
Item 21: Design interfaces for posterity 104
Item 22: Use interfaces only to define types 107
Item 23: Prefer class hierarchies to tagged classes 109
Item 24: Favor static member classes over nonstatic 112
Item 25: Limit source files to a single top-level class 115

Chapter 5: Generics 117
Item 26: Don’t use raw types 117
Item 27: Eliminate unchecked warnings 123
Item 28: Prefer lists to arrays 126
Item 29: Favor generic types 130
Item 30: Favor generic methods 135
Item 31: Use bounded wildcards to increase API flexibility 139
Item 32: Combine generics and varargs judiciously 146
Item 33: Consider typesafe heterogeneous containers 151

Chapter 6: Enums and Annotations 157
Item 34: Use enums instead of int constants 157
Item 35: Use instance fields instead of ordinals 168
Item 36: Use EnumSet instead of bit fields 169
Item 37: Use EnumMap instead of ordinal indexing 171
Item 38: Emulate extensible enums with interfaces 176
Item 39: Prefer annotations to naming patterns 180
Item 40: Consistently use the Override annotation 188
Item 41: Use marker interfaces to define types 191

Chapter 7: Lambdas and Streams 193
Item 42: Prefer lambdas to anonymous classes 193
Item 43: Prefer method references to lambdas 197
Item 44: Favor the use of standard functional interfaces 199
Item 45: Use streams judiciously 203
Item 46: Prefer side-effect-free functions in streams 210
Item 47: Prefer Collection to Stream as a return type 216
Item 48: Use caution when making streams parallel 222

Chapter 8: Methods 227
Item 49: Check parameters for validity 227
Item 50: Make defensive copies when needed 231
Item 51: Design method signatures carefully 236
Item 52: Use overloading judiciously 238
Item 53: Use varargs judiciously 245
Item 54: Return empty collections or arrays, not nulls 247
Item 55: Return optionals judiciously 249
Item 56: Write doc comments for all exposed API elements 254

Chapter 9: General Programming 261
Item 57: Minimize the scope of local variables 261
Item 58: Prefer for-each loops to traditional for loops 264
Item 59: Know and use the libraries 267
Item 60: Avoid float and double if exact answers are required 270
Item 61: Prefer primitive types to boxed primitives 273
Item 62: Avoid strings where other types are more appropriate 276
Item 63: Beware the performance of string concatenation 279
Item 64: Refer to objects by their interfaces 280
Item 65: Prefer interfaces to reflection 282
Item 66: Use native methods judiciously 285
Item 67: Optimize judiciously 286
Item 68: Adhere to generally accepted naming conventions 289

Chapter 10: Exceptions 293
Item 69: Use exceptions only for exceptional conditions 293
Item 70: Use checked exceptions for recoverable conditions and runtime exceptions for programming errors 296
Item 71: Avoid unnecessary use of checked exceptions 298
Item 72: Favor the use of standard exceptions 300
Item 73: Throw exceptions appropriate to the abstraction 302
Item 74: Document all exceptions thrown by each method 304
Item 75: Include failure-capture information in detail messages 306
Item 76: Strive for failure atomicity 308
Item 77: Don’t ignore exceptions 310

Chapter 11: Concurrency 311
Item 78: Synchronize access to shared mutable data 311
Item 79: Avoid excessive synchronization 317
Item 80: Prefer executors, tasks, and streams to threads 323
Item 81: Prefer concurrency utilities to wait and notify 325
Item 82: Document thread safety 330
Item 83: Use lazy initialization judiciously 333
Item 84: Don’t depend on the thread scheduler 336

Chapter 12: Serialization 339
Item 85: Prefer alternatives to Java serialization 339
Item 86: Implement Serializable with great caution 343
Item 87: Consider using a custom serialized form 346
Item 88: Write readObject methods defensively 353
Item 89: For instance control, prefer enum types to readResolve 359
Item 90: Consider serialization proxies instead of serialized instances 363

Items Corresponding to Second Edition 367
References 371
Index 377