scala.tools.nsc.backend.jvm

# BTypesFromSymbols

###
Related Doc: package jvm

#### class BTypesFromSymbols[G <: Global] extends BTypes

This class mainly contains the method classBTypeFromSymbol, which extracts the necessary information from a symbol and its type to create the corresponding ClassBType. It requires access to the compiler (global parameter).

The mixin CoreBTypes defines core BTypes that are used in the backend. Building these BTypes uses classBTypeFromSymbol, hence requires access to the compiler (global).

BTypesFromSymbols extends BTypes because the implementation of BTypes requires access to some of the core btypes. They are declared in BTypes as abstract members. Note that BTypes does not have access to the compiler instance.

Source
  BTypesFromSymbols.scala

Linear Supertypes
BTypes, AnyRef, Any
Type Hierarchy
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2. By Inheritance

Inherited

1. BTypesFromSymbols
2. BTypes
3. AnyRef
4. Any

Implicitly

1. by any2stringadd
2. by StringFormat
3. by Ensuring
4. by ArrowAssoc

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Visibility

1. Public
2. All

### Instance Constructors

1. #### new BTypesFromSymbols(global: G)

### Type Members

1. #### final case class ArrayBType(componentType: BType) extends RefBType with Product with Serializable

   Definition Classes
     BTypes

2. #### sealed trait BType extends AnyRef

   A BType is either a primitive type, a ClassBType, an ArrayBType of one of these, or a MethodType referring to BTypes.

   A BType is either a primitive type, a ClassBType, an ArrayBType of one of these, or a MethodType referring to BTypes.

   Definition Classes
     BTypes

3. #### final case class ClassBType(internalName: InternalName) extends RefBType with Product with Serializable

   A ClassBType represents a class or interface type.

   A ClassBType represents a class or interface type. The necessary information to build a ClassBType is extracted from compiler symbols and types, see BTypesFromSymbols.

   The `info` field contains either the class information on an error message why the info could not be computed. There are two reasons for an erroneous info:

   1. The ClassBType was built from a class symbol that stems from a java source file, and the symbol's type could not be completed successfully (SI-9111) 2. The ClassBType should be built from a classfile, but the class could not be found on the compilation classpath.

   Note that all ClassBTypes required in a non-optimized run are built during code generation from the class symbols referenced by the ASTs, so they have a valid info. Therefore the backend often invokes `info.get` (which asserts the info to exist) when reading data from the ClassBType.

   The inliner on the other hand uses ClassBTypes that are built from classfiles, which may have a missing info. In order not to crash the compiler unnecessarily, the inliner does not force infos using `get`, but it reports inliner warnings for missing infos that prevent inlining.

   Definition Classes
     BTypes

4. #### final case class ClassInfo(superClass: Option[ClassBType], interfaces: List[ClassBType], flags: Int, nestedClasses: List[ClassBType], nestedInfo: Option[NestedInfo], inlineInfo: InlineInfo) extends Product with Serializable

   The type info for a class.

   The type info for a class. Used for symboltable-independent subtype checks in the backend.

   superClass

     The super class, not defined for class java/lang/Object.

   interfaces

     All transitively implemented interfaces, except for those inherited through the superclass.

   flags

     The java flags, obtained through `javaFlags`. Used also to derive the flags for InnerClass entries.

   nestedClasses

     Classes nested in this class. Those need to be added to the InnerClass table, see the InnerClass spec summary above.

   nestedInfo

     If this describes a nested class, information for the InnerClass table.

   inlineInfo

     Information about this class for the inliner.

   Definition Classes
     BTypes

5. #### final case class InnerClassEntry(name: String, outerName: String, innerName: String, flags: Int) extends Product with Serializable

   This class holds the data for an entry in the InnerClass table.

   This class holds the data for an entry in the InnerClass table. See the InnerClass summary above in this file.

   There's some overlap with the class NestedInfo, but it's not exactly the same and cleaner to keep separate.

   name

     The internal name of the class.

   outerName

     The internal name of the outer class, may be null.

   innerName

     The simple name of the inner class, may be null.

   flags

     The flags for this class in the InnerClass entry.

   Definition Classes
     BTypes

6. #### final case class MethodBType(argumentTypes: List[BType], returnType: BType) extends BType with Product with Serializable

   Definition Classes
     BTypes

7. #### final case class MethodNameAndType(name: String, methodType: MethodBType) extends Product with Serializable

   Just a named pair, used in CoreBTypes.asmBoxTo/asmUnboxTo.

   Just a named pair, used in CoreBTypes.asmBoxTo/asmUnboxTo.

   Definition Classes
     BTypes

8. #### final case class NestedInfo(enclosingClass: ClassBType, outerName: Option[String], innerName: Option[String], isStaticNestedClass: Boolean) extends Product with Serializable

   Information required to add a class to an InnerClass table.

   Information required to add a class to an InnerClass table. The spec summary above explains what information is required for the InnerClass entry.

   enclosingClass

     The enclosing class, if it is also nested. When adding a class to the InnerClass table, enclosing nested classes are also added.

   outerName

     The outerName field in the InnerClass entry, may be None.

   innerName

     The innerName field, may be None.

   isStaticNestedClass

     True if this is a static nested class (not inner class) (*) (*) Note that the STATIC flag in ClassInfo.flags, obtained through javaFlags(classSym), is not correct for the InnerClass entry, see javaFlags. The static flag in the InnerClass describes a source-level property: if the class is in a static context (does not have an outer pointer). This is checked when building the NestedInfo.

   Definition Classes
     BTypes

9. #### sealed trait PrimitiveBType extends BType

   Definition Classes
     BTypes

10. #### sealed trait RefBType extends BType

    Definition Classes
      BTypes

### Value Members

1. #### final def !=(arg0: Any): Boolean

   Test two objects for inequality.

   Test two objects for inequality.

   returns

     `true` if !(this == that), false otherwise.

   Definition Classes
     AnyRef → Any

2. #### final def ##(): Int

   Equivalent to `x.hashCode` except for boxed numeric types and `null`.

   Equivalent to `x.hashCode` except for boxed numeric types and `null`. For numerics, it returns a hash value which is consistent with value equality: if two value type instances compare as true, then ## will produce the same hash value for each of them. For `null` returns a hashcode where `null.hashCode` throws a `NullPointerException`.

   returns

     a hash value consistent with ==

   Definition Classes
     AnyRef → Any

3. #### def +(other: String): String

   Implicit information
     This member is added by an implicit conversion from BTypesFromSymbols[G] to any2stringadd[BTypesFromSymbols[G]] performed by method any2stringadd in scala.Predef.
   Definition Classes
     any2stringadd

4. #### def ->[B](y: B): (BTypesFromSymbols[G], B)

   Implicit information
     This member is added by an implicit conversion from BTypesFromSymbols[G] to ArrowAssoc[BTypesFromSymbols[G]] performed by method ArrowAssoc in scala.Predef.
   Definition Classes
     ArrowAssoc
   Annotations
     @inline()

5. #### final def ==(arg0: Any): Boolean

   The expression `x == that` is equivalent to `if (x eq null) that eq null else x.equals(that)`.

   The expression `x == that` is equivalent to `if (x eq null) that eq null else x.equals(that)`.

   returns

     `true` if the receiver object is equivalent to the argument; `false` otherwise.

   Definition Classes
     AnyRef → Any

6. #### object BOOL extends PrimitiveBType with Product with Serializable

   Definition Classes
     BTypes

7. #### object BYTE extends PrimitiveBType with Product with Serializable

   Definition Classes
     BTypes

8. #### object CHAR extends PrimitiveBType with Product with Serializable

   Definition Classes
     BTypes

9. #### object ClassBType extends Serializable

   Definition Classes
     BTypes

10. #### object DOUBLE extends PrimitiveBType with Product with Serializable

    Definition Classes
      BTypes

11. #### object FLOAT extends PrimitiveBType with Product with Serializable

    Definition Classes
      BTypes

12. #### object INT extends PrimitiveBType with Product with Serializable

    Definition Classes
      BTypes

13. #### object LONG extends PrimitiveBType with Product with Serializable

    Definition Classes
      BTypes

14. #### object SHORT extends PrimitiveBType with Product with Serializable

    Definition Classes
      BTypes

15. #### object UNIT extends PrimitiveBType with Product with Serializable

    Definition Classes
      BTypes

16. #### final def asInstanceOf[T0]: T0

    Cast the receiver object to be of type `T0`.

    Cast the receiver object to be of type `T0`.

    Note that the success of a cast at runtime is modulo Scala's erasure semantics. Therefore the expression `1.asInstanceOf[String]` will throw a `ClassCastException` at runtime, while the expression `List(1).asInstanceOf[List[String]]` will not. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the requested type.

    returns

      the receiver object.

    Definition Classes
      Any
    Exceptions thrown

      `ClassCastException` if the receiver object is not an instance of the erasure of type `T0`.

17. #### def assertClassNotArray(sym: G.Symbol): Unit

18. #### def assertClassNotArrayNotPrimitive(sym: G.Symbol): Unit

19. #### val bCodeAsmCommon: BCodeAsmCommon[global.type]

20. #### val bCodeICodeCommon: BCodeICodeCommon[global.type]

21. #### def bTypeForDescriptorOrInternalNameFromClassfile(desc: String): BType

    Obtain the BType for a type descriptor or internal name.

    Obtain the BType for a type descriptor or internal name. For class descriptors, the ClassBType is constructed by parsing the corresponding classfile.

    Some JVM operations use either a full descriptor or only an internal name. Example: ANEWARRAY java/lang/String // a new array of strings (internal name for the String class) ANEWARRAY [Ljava/lang/String; // a new array of array of string (full descriptor for the String class)

    This method supports both descriptors and internal names.

    Definition Classes
      BTypes

22. #### val backendReporting: BackendReporting

    Definition Classes
      BTypesFromSymbols → BTypes

23. #### val byteCodeRepository: ByteCodeRepository

    Tools for parsing classfiles, used by the inliner.

    Tools for parsing classfiles, used by the inliner.

    Definition Classes
      BTypesFromSymbols → BTypes

24. #### val callGraph: CallGraph[BTypesFromSymbols.this.type]

    Definition Classes
      BTypesFromSymbols → BTypes

25. #### val callsitePositions: Map[MethodInsnNode, Position]

    Store the position of every MethodInsnNode during code generation.

    Store the position of every MethodInsnNode during code generation. This allows each callsite in the call graph to remember its source position, which is required for inliner warnings.

    Definition Classes
      BTypes

26. #### def classBTypeFromClassNode(classNode: ClassNode): ClassBType

    Construct the ClassBType for a parsed classfile.

    Construct the ClassBType for a parsed classfile.

    Definition Classes
      BTypes

27. #### val classBTypeFromInternalName: Map[InternalName, ClassBType]

    A map from internal names to ClassBTypes.

    A map from internal names to ClassBTypes. Every ClassBType is added to this map on its construction.

    This map is used when computing stack map frames. The asm.ClassWriter invokes the method `getCommonSuperClass`. In this method we need to obtain the ClassBType for a given internal name. The method assumes that every class type that appears in the bytecode exists in the map.

    Concurrent because stack map frames are computed when in the class writer, which might run on multiple classes concurrently.

    Definition Classes
      BTypes

28. #### def classBTypeFromParsedClassfile(internalName: InternalName): ClassBType

    Parse the classfile for `internalName` and construct the ClassBType.

    Parse the classfile for `internalName` and construct the ClassBType. If the classfile cannot be found in the `byteCodeRepository`, the `info` of the resulting ClassBType is undefined.

    Definition Classes
      BTypes

29. #### final def classBTypeFromSymbol(classSym: G.Symbol): ClassBType

    The ClassBType for a class symbol `classSym`.

    The ClassBType for a class symbol `classSym`.

    The class symbol scala.Nothing is mapped to the class scala.runtime.Nothing$. Similarly, scala.Null is mapped to scala.runtime.Null$. This is because there exist no class files for the Nothing / Null. If used for example as a parameter type, we use the runtime classes in the classfile method signature.

    Note that the referenced class symbol may be an implementation class. For example when compiling a mixed-in method that forwards to the static method in the implementation class, the class descriptor of the receiver (the implementation class) is obtained by creating the ClassBType.

30. #### def clone(): AnyRef

    Create a copy of the receiver object.

    Create a copy of the receiver object.

    The default implementation of the `clone` method is platform dependent.

    returns

      a copy of the receiver object.

    Attributes
      protected[java.lang]
    Definition Classes
      AnyRef
    Annotations
      @throws( ... )
    Note

      not specified by SLS as a member of AnyRef

31. #### val closureOptimizer: ClosureOptimizer[BTypesFromSymbols.this.type]

    Definition Classes
      BTypesFromSymbols → BTypes

32. #### def compilerSettings: ScalaSettings

    Definition Classes
      BTypesFromSymbols → BTypes

33. #### val coreBTypes: CoreBTypesProxy[BTypesFromSymbols.this.type]

    Definition Classes
      BTypesFromSymbols → BTypes

34. #### def ensuring(cond: (BTypesFromSymbols[G]) ⇒ Boolean, msg: ⇒ Any): BTypesFromSymbols[G]

    Implicit information
      This member is added by an implicit conversion from BTypesFromSymbols[G] to Ensuring[BTypesFromSymbols[G]] performed by method Ensuring in scala.Predef.
    Definition Classes
      Ensuring

35. #### def ensuring(cond: (BTypesFromSymbols[G]) ⇒ Boolean): BTypesFromSymbols[G]

    Implicit information
      This member is added by an implicit conversion from BTypesFromSymbols[G] to Ensuring[BTypesFromSymbols[G]] performed by method Ensuring in scala.Predef.
    Definition Classes
      Ensuring

36. #### def ensuring(cond: Boolean, msg: ⇒ Any): BTypesFromSymbols[G]

    Implicit information
      This member is added by an implicit conversion from BTypesFromSymbols[G] to Ensuring[BTypesFromSymbols[G]] performed by method Ensuring in scala.Predef.
    Definition Classes
      Ensuring

37. #### def ensuring(cond: Boolean): BTypesFromSymbols[G]

    Implicit information
      This member is added by an implicit conversion from BTypesFromSymbols[G] to Ensuring[BTypesFromSymbols[G]] performed by method Ensuring in scala.Predef.
    Definition Classes
      Ensuring

38. #### final def eq(arg0: AnyRef): Boolean

    Tests whether the argument (`that`) is a reference to the receiver object (`this`).

    Tests whether the argument (`that`) is a reference to the receiver object (`this`).

    The `eq` method implements an equivalence relation on non-null instances of `AnyRef`, and has three additional properties:

    - It is consistent: for any non-null instances `x` and `y` of type `AnyRef`, multiple invocations of `x.eq(y)` consistently returns `true` or consistently returns `false`.
    - For any non-null instance `x` of type `AnyRef`, `x.eq(null)` and `null.eq(x)` returns `false`.
    - `null.eq(null)` returns `true`.

    When overriding the `equals` or `hashCode` methods, it is important to ensure that their behavior is consistent with reference equality. Therefore, if two objects are references to each other (`o1 eq o2`), they should be equal to each other (`o1 == o2`) and they should hash to the same value (`o1.hashCode == o2.hashCode`).

    returns

      `true` if the argument is a reference to the receiver object; `false` otherwise.

    Definition Classes
      AnyRef

39. #### def equals(arg0: Any): Boolean

    The equality method for reference types.

    The equality method for reference types. Default implementation delegates to `eq`.

    See also `equals` in scala.Any.

    returns

      `true` if the receiver object is equivalent to the argument; `false` otherwise.

    Definition Classes
      AnyRef → Any

40. #### def finalize(): Unit

    Called by the garbage collector on the receiver object when there are no more references to the object.

    Called by the garbage collector on the receiver object when there are no more references to the object.

    The details of when and if the `finalize` method is invoked, as well as the interaction between `finalize` and non-local returns and exceptions, are all platform dependent.

    Attributes
      protected[java.lang]
    Definition Classes
      AnyRef
    Annotations
      @throws( classOf[java.lang.Throwable] )
    Note

      not specified by SLS as a member of AnyRef

41. #### def formatted(fmtstr: String): String

    Implicit information
      This member is added by an implicit conversion from BTypesFromSymbols[G] to StringFormat[BTypesFromSymbols[G]] performed by method StringFormat in scala.Predef.
    Definition Classes
      StringFormat
    Annotations
      @inline()

42. #### final def getClass(): Class[_]

    A representation that corresponds to the dynamic class of the receiver object.

    A representation that corresponds to the dynamic class of the receiver object.

    The nature of the representation is platform dependent.

    returns

      a representation that corresponds to the dynamic class of the receiver object.

    Definition Classes
      AnyRef → Any
    Note

      not specified by SLS as a member of AnyRef

43. #### val global: G

44. #### final def hasPublicBitSet(flags: Int): Boolean

45. #### def hashCode(): Int

    The hashCode method for reference types.

    The hashCode method for reference types. See hashCode in scala.Any.

    returns

      the hash code value for this object.

    Definition Classes
      AnyRef → Any

46. #### final def initializeCoreBTypes(): Unit

47. #### def inlineInfoFromClassfile(classNode: ClassNode): InlineInfo

    Build the InlineInfo for a class.

    Build the InlineInfo for a class. For Scala classes, the information is stored in the ScalaInlineInfo attribute. If the attribute is missing, the InlineInfo is built using the metadata available in the classfile (ACC_FINAL flags, etc).

    Definition Classes
      BTypes

48. #### val inliner: Inliner[BTypesFromSymbols.this.type]

    Definition Classes
      BTypesFromSymbols → BTypes

49. #### def isCompilingArray: Boolean

50. #### def isCompilingPrimitive: Boolean

    True if the current compilation unit is of a primitive class (scala.Boolean et al).

    True if the current compilation unit is of a primitive class (scala.Boolean et al). Used only in assertions.

    Definition Classes
      BTypesFromSymbols → BTypes

51. #### final def isInstanceOf[T0]: Boolean

    Test whether the dynamic type of the receiver object is `T0`.

    Test whether the dynamic type of the receiver object is `T0`.

    Note that the result of the test is modulo Scala's erasure semantics. Therefore the expression `1.isInstanceOf[String]` will return `false`, while the expression `List(1).isInstanceOf[List[String]]` will return `true`. In the latter example, because the type argument is erased as part of compilation it is not possible to check whether the contents of the list are of the specified type.

    returns

      `true` if the receiver object is an instance of erasure of type `T0`; `false` otherwise.

    Definition Classes
      Any

52. #### final def isRemote(s: G.Symbol): Boolean

53. #### final def isStaticModuleClass(sym: G.Symbol): Boolean

    True for module classes of modules that are top-level or owned only by objects.

    True for module classes of modules that are top-level or owned only by objects. Module classes for such objects will get a MODULE$ flag and a corresponding static initializer.

54. #### final def isTopLevelModuleClass(sym: G.Symbol): Boolean

    True for module classes of package level objects.

    True for module classes of package level objects. The backend will generate a mirror class for such objects.

55. #### val javaDefinedClasses: Set[InternalName]

    Contains the internal names of all classes that are defined in Java source files of the current compilation run (mixed compilation).

    Contains the internal names of all classes that are defined in Java source files of the current compilation run (mixed compilation). Used for more detailed error reporting.

    Definition Classes
      BTypes

56. #### def javaFieldFlags(sym: G.Symbol): Int

57. #### final def javaFlags(sym: G.Symbol): Int

    Return the Java modifiers for the given symbol.

    Return the Java modifiers for the given symbol. Java modifiers for classes:

    - public, abstract, final, strictfp (not used) for interfaces:
    - the same as for classes, without 'final' for fields:
    - public, private (*)
    - static, final for methods:
    - the same as for fields, plus:
    - abstract, synchronized (not used), strictfp (not used), native (not used) for all:
    - deprecated

    (*) protected cannot be used, since inner classes 'see' protected members, and they would fail verification after lifted.

58. #### val localOpt: LocalOpt[BTypesFromSymbols.this.type]

    Definition Classes
      BTypesFromSymbols → BTypes

59. #### final def methodBTypeFromSymbol(methodSymbol: G.Symbol): MethodBType

    Builds a MethodBType for a method symbol.

60. #### def mirrorClassClassBType(moduleClassSym: G.Symbol): ClassBType

    For top-level objects without a companion class, the compilere generates a mirror class with static forwarders (Java compat).

    For top-level objects without a companion class, the compilere generates a mirror class with static forwarders (Java compat). There's no symbol for the mirror class, but we still need a ClassBType (its info.nestedClasses will hold the InnerClass entries, see comment in BTypes).

61. #### final def ne(arg0: AnyRef): Boolean

    Equivalent to `!(this eq that)`.

    Equivalent to `!(this eq that)`.

    returns

      `true` if the argument is not a reference to the receiver object; `false` otherwise.

    Definition Classes
      AnyRef

62. #### final def notify(): Unit

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Wakes up a single thread that is waiting on the receiver object's monitor.

    Definition Classes
      AnyRef
    Note

      not specified by SLS as a member of AnyRef

63. #### final def notifyAll(): Unit

    Wakes up all threads that are waiting on the receiver object's monitor.

    Wakes up all threads that are waiting on the receiver object's monitor.

    Definition Classes
      AnyRef
    Note

      not specified by SLS as a member of AnyRef

64. #### def recordPerRunCache[T <: Clearable](cache: T): T

    Definition Classes
      BTypesFromSymbols → BTypes

65. #### final val strMODULE_INSTANCE_FIELD: String

66. #### final def synchronized[T0](arg0: ⇒ T0): T0

    Definition Classes
      AnyRef

67. #### def toString(): String

    Creates a String representation of this object.

    Creates a String representation of this object. The default representation is platform dependent. On the java platform it is the concatenation of the class name, "@", and the object's hashcode in hexadecimal.

    returns

      a String representation of the object.

    Definition Classes
      AnyRef → Any

68. #### final def typeToBType(t: G.Type): BType

    This method returns the BType for a type reference, for example a parameter type.

    This method returns the BType for a type reference, for example a parameter type.

    If `t` references a class, typeToBType ensures that the class is not an implementation class. See also comment on classBTypeFromSymbol, which is invoked for implementation classes.

69. #### val unreachableCodeEliminated: Set[MethodNode]

    Cache, contains methods whose unreachable instructions are eliminated.

    Cache, contains methods whose unreachable instructions are eliminated.

    The ASM Analyzer class does not compute any frame information for unreachable instructions. Transformations that use an analyzer (including inlining) therefore require unreachable code to be eliminated.

    This cache allows running dead code elimination whenever an analyzer is used. If the method is already optimized, DCE can return early.

    Definition Classes
      BTypes

70. #### final def wait(): Unit

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

71. #### final def wait(arg0: Long, arg1: Int): Unit

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

72. #### final def wait(arg0: Long): Unit

    Definition Classes
      AnyRef
    Annotations
      @throws( ... )

73. #### def →[B](y: B): (BTypesFromSymbols[G], B)

    Implicit information
      This member is added by an implicit conversion from BTypesFromSymbols[G] to ArrowAssoc[BTypesFromSymbols[G]] performed by method ArrowAssoc in scala.Predef.
    Definition Classes
      ArrowAssoc

### Inherited from BTypes

### Inherited from AnyRef

### Inherited from Any

### Inherited by implicit conversion any2stringadd from BTypesFromSymbols[G] to any2stringadd[BTypesFromSymbols[G]]

### Inherited by implicit conversion StringFormat from BTypesFromSymbols[G] to StringFormat[BTypesFromSymbols[G]]

### Inherited by implicit conversion Ensuring from BTypesFromSymbols[G] to Ensuring[BTypesFromSymbols[G]]

### Inherited by implicit conversion ArrowAssoc from BTypesFromSymbols[G] to ArrowAssoc[BTypesFromSymbols[G]]

### Ungrouped