book

Effective Java, 3rd Edition

by Joshua Bloch

December 2017

Intermediate to advanced

416 pages

13h 31m

English

Addison-Wesley Professional

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Item 1: Consider static factory methods instead of constructorsItem 2: Consider a builder when faced with many constructor parametersItem 3: Enforce the singleton property with a private constructor or an enum typeItem 4: Enforce noninstantiability with a private constructorItem 5: Prefer dependency injection to hardwiring resourcesItem 6: Avoid creating unnecessary objectsItem 7: Eliminate obsolete object referencesItem 8: Avoid finalizers and cleanersItem 9: Prefer try-with-resources to try-finally
Item 10: Obey the general contract when overriding equalsItem 11: Always override hashCode when you override equalsItem 12: Always override toStringItem 13: Override clone judiciouslyItem 14: Consider implementing Comparable
Item 15: Minimize the accessibility of classes and membersItem 16: In public classes, use accessor methods, not public fieldsItem 17: Minimize mutabilityItem 18: Favor composition over inheritanceItem 19: Design and document for inheritance or else prohibit itItem 20: Prefer interfaces to abstract classesItem 21: Design interfaces for posterityItem 22: Use interfaces only to define typesItem 23: Prefer class hierarchies to tagged classesItem 24: Favor static member classes over nonstaticItem 25: Limit source files to a single top-level class
Item 26: Don’t use raw typesItem 27: Eliminate unchecked warningsItem 28: Prefer lists to arraysItem 29: Favor generic typesItem 30: Favor generic methodsItem 31: Use bounded wildcards to increase API flexibilityItem 32: Combine generics and varargs judiciouslyItem 33: Consider typesafe heterogeneous containers
Item 34: Use enums instead of int constantsItem 35: Use instance fields instead of ordinalsItem 36: Use EnumSet instead of bit fieldsItem 37: Use EnumMap instead of ordinal indexingItem 38: Emulate extensible enums with interfacesItem 39: Prefer annotations to naming patternsItem 40: Consistently use the Override annotationItem 41: Use marker interfaces to define types
Item 42: Prefer lambdas to anonymous classesItem 43: Prefer method references to lambdasItem 44: Favor the use of standard functional interfacesItem 45: Use streams judiciouslyItem 46: Prefer side-effect-free functions in streamsItem 47: Prefer Collection to Stream as a return typeItem 48: Use caution when making streams parallel
Item 49: Check parameters for validityItem 50: Make defensive copies when neededItem 51: Design method signatures carefullyItem 52: Use overloading judiciouslyItem 53: Use varargs judiciouslyItem 54: Return empty collections or arrays, not nullsItem 55: Return optionals judiciouslyItem 56: Write doc comments for all exposed API elements
Item 57: Minimize the scope of local variablesItem 58: Prefer for-each loops to traditional for loopsItem 59: Know and use the librariesItem 60: Avoid float and double if exact answers are requiredItem 61: Prefer primitive types to boxed primitivesItem 62: Avoid strings where other types are more appropriateItem 63: Beware the performance of string concatenationItem 64: Refer to objects by their interfacesItem 65: Prefer interfaces to reflectionItem 66: Use native methods judiciouslyItem 67: Optimize judiciouslyItem 68: Adhere to generally accepted naming conventions
Item 69: Use exceptions only for exceptional conditionsItem 70: Use checked exceptions for recoverable conditions and runtime exceptions for programming errorsItem 71: Avoid unnecessary use of checked exceptionsItem 72: Favor the use of standard exceptionsItem 73: Throw exceptions appropriate to the abstractionItem 74: Document all exceptions thrown by each methodItem 75: Include failure-capture information in detail messagesItem 76: Strive for failure atomicityItem 77: Don’t ignore exceptions
Item 78: Synchronize access to shared mutable dataItem 79: Avoid excessive synchronizationItem 80: Prefer executors, tasks, and streams to threadsItem 81: Prefer concurrency utilities to wait and notifyItem 82: Document thread safetyItem 83: Use lazy initialization judiciouslyItem 84: Don’t depend on the thread scheduler
Item 85: Prefer alternatives to Java serializationItem 86: Implement Serializable with great cautionItem 87: Consider using a custom serialized formItem 88: Write readObject methods defensivelyItem 89: For instance control, prefer enum types to readResolveItem 90: Consider serialization proxies instead of serialized instances

Content preview from Effective Java, 3rd Edition

Chapter 2. Creating and Destroying Objects

THIS chapter concerns creating and destroying objects: when and how to create them, when and how to avoid creating them, how to ensure they are destroyed in a timely manner, and how to manage any cleanup actions that must precede their destruction.

Item 1: Consider static factory methods instead of constructors

The traditional way for a class to allow a client to obtain an instance is to provide a public constructor. There is another technique that should be a part of every programmer’s toolkit. A class can provide a public static factory method, which is simply a static method that returns an instance of the class. Here’s a simple example from Boolean (the boxed primitive class for boolean). This method ...