201-book-effective-java.mdc

---
description: Extension to java rules from the book "Effective Java"
globs: .java
alwaysApply: true
---
# Development Guidelines: effective_java_notes:

  chapter_2:
    title: "Creating and Destroying Objects"
    items:
      - "Consider static factory methods instead of constructors"
      - "Consider a builder when faced with many constructor parameters"
      - "Enforce the singleton property with a private constructor or an enum type"
      - "Enforce noninstantiability with a private constructor"
      - "Prefer dependency injection to hardwiring resources"
      - "Avoid creating unnecessary objects"
      - "Eliminate obsolete object references"
      - "Avoid finalizers and cleaners"
      - "Prefer try-with-resources to try-finally"

  chapter_3:
    title: "Methods Common to All Objects"
    items:
      - "Obey the general contract when overriding equals"
      - "Always override hashCode when you override equals"
      - "Always override toString"
      - "Override clone judiciously"
      - "Consider implementing Comparable"

  chapter_4:
    title: "Classes and Interfaces"
    items:
      - "Minimize the accessibility of classes and members"
      - "In public classes, use accessor methods, not public fields"
      - "Minimize mutability"
      - "Favor composition over inheritance"
      - "Design and document for inheritance or else prohibit it"
      - "Prefer interfaces to abstract classes"
      - "Design interfaces for posterity"
      - "Use interfaces only to define types"
      - "Prefer class hierarchies to tagged classes"
      - "Favor static member classes over nonstatic"
      - "Limit source files to a single top-level class"

  chapter_5:
    title: "Generics"
    items:
      - "Don't use raw types"
      - "Eliminate unchecked warnings"
      - "Prefer lists to arrays"
      - "Favor generic types"
      - "Favor generic methods"
      - "Use bounded wildcards to increase API flexibility"
      - "Combine generics and varargs judiciously"
      - "Consider typesafe heterogeneous containers"

  chapter_6:
    title: "Enums and Annotations"
    items:
      - "Use enums instead of int constants"
      - "Use instance fields instead of ordinals"
      - "Use EnumSet instead of bit fields"
      - "Use EnumMap instead of ordinal indexing"
      - "Emulate extensible enums with interfaces"
      - "Prefer annotations to naming patterns"
      - "Consistently use the Override annotation"
      - "Use marker interfaces to define types"

  chapter_7:
    title: "Lambdas and Streams"
    items:
      - "Prefer lambdas to anonymous classes"
      - "Prefer method references to lambdas"
      - "Favor the use of standard functional interfaces"
      - "Use streams judiciously"
      - "Prefer side-effect-free functions in streams"
      - "Prefer Collection to Stream as a return type"
      - "Use caution when making streams parallel"

  chapter_8:
    title: "Methods"
    items:
      - "Check parameters for validity"
      - "Make defensive copies when needed"
      - "Design method signatures carefully"
      - "Use overloading judiciously"
      - "Use varargs judiciously"
      - "Return empty collections or arrays, not nulls"
      - "Return optionals judiciously"
      - "Write doc comments for all exposed API elements"

  chapter_9:
    title: "General Programming"
    items:
      - "Minimize the scope of local variables"
      - "Prefer for-each loops to traditional for loops"
      - "Know and use the libraries"
      - "Avoid float and double if exact answers are required"
      - "Prefer primitive types to boxed primitives"
      - "Avoid strings where other types are more appropriate"
      - "Beware the performance of string concatenation"
      - "Refer to objects by their interfaces"
      - "Prefer interfaces to reflection"
      - "Use native methods judiciously"
      - "Optimize judiciously"
      - "Adhere to generally accepted naming conventions"

  chapter_10:
    title: "Exceptions"
    items:
      - "Use exceptions only for exceptional conditions"
      - "Use checked exceptions for recoverable conditions and runtime exceptions for programming errors"
      - "Avoid unnecessary use of checked exceptions"
      - "Favor the use of standard exceptions"
      - "Throw exceptions appropriate to the abstraction"
      - "Document all exceptions thrown by each method"
      - "Include failure-capture information in detail messages"
      - "Strive for failure atomicity"
      - "Don't ignore exceptions"

  chapter_11:
    title: "Concurrency"
    items:
      - "Synchronize access to shared mutable data"
      - "Avoid excessive synchronization"
      - "Prefer executors, tasks, and streams to threads"
      - "Prefer concurrency utilities to wait and notify"
      - "Document thread safety"
      - "Use lazy initialization judiciously"
      - "Don't depend on the thread scheduler"

  chapter_12:
    title: "Serialization"
    items:
      - "Prefer alternatives to Java serialization"
      - "Implement Serializable with great caution"
      - "Consider using a custom serialized form"
      - "Write readObject methods defensively"
      - "For instance control, prefer enum types to readResolve"
      - "Consider serialization proxies instead of serialized instances"