ClassReader (jdk.compiler 1.8.132 API)

java.lang.Object
- com.sun.tools.javac.jvm.ClassReader

```
public class ClassReader
extends Object
```
This class provides operations to read a classfile into an internal representation. The internal representation is anchored in a ClassSymbol which contains in its scope symbol representations for all other definitions in the classfile. Top-level Classes themselves appear as members of the scopes of PackageSymbols.
This is NOT part of any supported API. If you write code that depends on this, you do so at your own risk. This code and its internal interfaces are subject to change or deletion without notice.

Nested Class Summary

Nested Classes
Modifier and Type	Class and Description
`protected static class`	`ClassReader.AttributeKind` Reading Attributes
`protected class`	`ClassReader.AttributeReader`
`class`	`ClassReader.BadClassFile` Error Diagnoses
`static interface`	`ClassReader.SourceCompleter`

Field Summary

Fields
Modifier and Type	Field and Description
`protected Map<Name,ClassReader.AttributeReader>`	`attributeReaders`
`protected int`	`bp` The current input pointer.
`protected Set<ClassReader.AttributeKind>`	`CLASS_ATTRIBUTE`
`protected Set<ClassReader.AttributeKind>`	`CLASS_OR_MEMBER_ATTRIBUTE`
`protected static Context.Key<ClassReader>`	`classReaderKey` The context key for the class reader.
`protected JavaFileObject`	`currentClassFile` The path name of the class file currently being read.
`protected JavaFileManager.Location`	`currentLoc`
`protected Symbol`	`currentOwner` The class or method currently being read.
`static int`	`INITIAL_BUFFER_SIZE`
`protected Set<ClassReader.AttributeKind>`	`MEMBER_ATTRIBUTE`
`boolean`	`preferSource` Switch: prefer source files instead of newer when both source and class are available
`Profile`	`profile` The currently selected profile.
`boolean`	`readAllOfClassFile` Switch: read constant pool and code sections.
`boolean`	`saveParameterNames` Switch: preserve parameter names from the variable table.
`ClassReader.SourceCompleter`	`sourceCompleter` Can be reassigned from outside: the completer to be used for ".java" files.
`protected Scope`	`typevars` The current scope where type variables are entered.

Constructor Summary

Constructors
Modifier	Constructor and Description
`protected`	`ClassReader(Context context, boolean definitive)` Construct a new class reader, optionally treated as the definitive classreader for this invocation.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`ClassReader.BadClassFile`	`badClassFile(String key, Object... args)`
`Symbol.ClassSymbol`	`defineClass(Name name, Symbol owner)` Define a new class given its name and owner.
`Symbol.ClassSymbol`	`enterClass(Name flatname)` Create a new member or toplevel class symbol with given flat name and enter in `classes' unless already there.
`Symbol.ClassSymbol`	`enterClass(Name flatName, JavaFileObject classFile)` Creates a new toplevel class symbol with given flat name and given class (or source) file.
`Symbol.ClassSymbol`	`enterClass(Name name, Symbol.TypeSymbol owner)` Create a new toplevel or member class symbol with given name and owner and enter in `classes' unless already there.
`Symbol.PackageSymbol`	`enterPackage(Name fullname)` Make a package, given its fully qualified name.
`Symbol.PackageSymbol`	`enterPackage(Name name, Symbol.PackageSymbol owner)` Make a package, given its unqualified name and enclosing package.
`protected void`	`enterTypevars(Symbol sym)`
`protected void`	`enterTypevars(Type t)` Enter type variables of this classtype and all enclosing ones in `typevars'.
`protected void`	`extraFileActions(Symbol.PackageSymbol pack, JavaFileObject fe)` this is used to support javadoc
`protected EnumSet<JavaFileObject.Kind>`	`getPackageFileKinds()` specifies types of files to be read when filling in a package symbol
`protected void`	`includeClassFile(Symbol.PackageSymbol p, JavaFileObject file)` Include class corresponding to given class file in package, unless (1) we already have one the same kind (.class or .java), or (2) we have one of the other kind, and the given class file is older.
`void`	`init(Symtab syms)` Initialize classes and packages, treating this as the definitive classreader.
`static ClassReader`	`instance(Context context)` Get the ClassReader instance for this invocation.
`Symbol.ClassSymbol`	`loadClass(Name flatname)` Load a toplevel class with given fully qualified name The class is entered into `classes' only if load was successful.
`boolean`	`packageExists(Name fullname)` Check to see if a package exists, given its fully qualified name.
`protected JavaFileObject`	`preferredFileObject(JavaFileObject a, JavaFileObject b)` Implement policy to choose to derive information from a source file or a class file when both are present.
`protected void`	`readEnclosingMethodAttr(Symbol sym)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - classReaderKey
```
protected static final Context.Key<ClassReader> classReaderKey
```
    The context key for the class reader.
  - INITIAL_BUFFER_SIZE
```
public static final int INITIAL_BUFFER_SIZE
```
    See Also:
    
    Constant Field Values
  - readAllOfClassFile
```
public boolean readAllOfClassFile
```
    Switch: read constant pool and code sections. This switch is initially set to false but can be turned on from outside.
  - saveParameterNames
```
public boolean saveParameterNames
```
    Switch: preserve parameter names from the variable table.
  - preferSource
```
public boolean preferSource
```
    Switch: prefer source files instead of newer when both source and class are available
  - profile
```
public final Profile profile
```
    The currently selected profile.
  - sourceCompleter
```
public ClassReader.SourceCompleter sourceCompleter
```
    Can be reassigned from outside: the completer to be used for ".java" files. If this remains unassigned ".java" files will not be loaded.
  - typevars
```
protected Scope typevars
```
    The current scope where type variables are entered.
  - currentClassFile
```
protected JavaFileObject currentClassFile
```
    The path name of the class file currently being read.
  - currentOwner
```
protected Symbol currentOwner
```
    The class or method currently being read.
  - bp
```
protected int bp
```
    The current input pointer.
  - CLASS_ATTRIBUTE
```
protected Set<ClassReader.AttributeKind> CLASS_ATTRIBUTE
```
  - MEMBER_ATTRIBUTE
```
protected Set<ClassReader.AttributeKind> MEMBER_ATTRIBUTE
```
  - CLASS_OR_MEMBER_ATTRIBUTE
```
protected Set<ClassReader.AttributeKind> CLASS_OR_MEMBER_ATTRIBUTE
```
  - attributeReaders
```
protected Map<Name,ClassReader.AttributeReader> attributeReaders
```
  - currentLoc
```
protected JavaFileManager.Location currentLoc
```
- Constructor Detail
  - ClassReader
```
protected ClassReader(Context context,
                      boolean definitive)
```
    Construct a new class reader, optionally treated as the definitive classreader for this invocation.
- Method Detail
  - instance
```
public static ClassReader instance(Context context)
```
    Get the ClassReader instance for this invocation.
  - init
```
public void init(Symtab syms)
```
    Initialize classes and packages, treating this as the definitive classreader.
  - badClassFile
```
public ClassReader.BadClassFile badClassFile(String key,
                                             Object... args)
```
  - readEnclosingMethodAttr
```
protected void readEnclosingMethodAttr(Symbol sym)
```
  - enterTypevars
```
protected void enterTypevars(Type t)
```
    Enter type variables of this classtype and all enclosing ones in `typevars'.
  - enterTypevars
```
protected void enterTypevars(Symbol sym)
```
  - defineClass
```
public Symbol.ClassSymbol defineClass(Name name,
                                      Symbol owner)
```
    Define a new class given its name and owner.
  - enterClass
```
public Symbol.ClassSymbol enterClass(Name name,
                                     Symbol.TypeSymbol owner)
```
    Create a new toplevel or member class symbol with given name and owner and enter in `classes' unless already there.
  - enterClass
```
public Symbol.ClassSymbol enterClass(Name flatName,
                                     JavaFileObject classFile)
```
    Creates a new toplevel class symbol with given flat name and given class (or source) file.
    
    Parameters:
    
    flatName - a fully qualified binary class name
    
    classFile - the class file or compilation unit defining the class (may be null)
    
    Returns:
    
    a newly created class symbol
    
    Throws:
    
    AssertionError - if the class symbol already exists
  - enterClass
```
public Symbol.ClassSymbol enterClass(Name flatname)
```
    Create a new member or toplevel class symbol with given flat name and enter in `classes' unless already there.
  - loadClass
```
public Symbol.ClassSymbol loadClass(Name flatname)
                             throws Symbol.CompletionFailure
```
    Load a toplevel class with given fully qualified name The class is entered into `classes' only if load was successful.
    
    Throws:
    
    Symbol.CompletionFailure
  - packageExists
```
public boolean packageExists(Name fullname)
```
    Check to see if a package exists, given its fully qualified name.
  - enterPackage
```
public Symbol.PackageSymbol enterPackage(Name fullname)
```
    Make a package, given its fully qualified name.
  - enterPackage
```
public Symbol.PackageSymbol enterPackage(Name name,
                                         Symbol.PackageSymbol owner)
```
    Make a package, given its unqualified name and enclosing package.
  - includeClassFile
```
protected void includeClassFile(Symbol.PackageSymbol p,
                                JavaFileObject file)
```
    Include class corresponding to given class file in package, unless (1) we already have one the same kind (.class or .java), or (2) we have one of the other kind, and the given class file is older.
  - preferredFileObject
```
protected JavaFileObject preferredFileObject(JavaFileObject a,
                                             JavaFileObject b)
```
    Implement policy to choose to derive information from a source file or a class file when both are present. May be overridden by subclasses.
  - getPackageFileKinds
```
protected EnumSet<JavaFileObject.Kind> getPackageFileKinds()
```
    specifies types of files to be read when filling in a package symbol
  - extraFileActions
```
protected void extraFileActions(Symbol.PackageSymbol pack,
                                JavaFileObject fe)
```
    this is used to support javadoc

Class ClassReader

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

classReaderKey

INITIAL_BUFFER_SIZE

readAllOfClassFile

saveParameterNames

preferSource

profile

sourceCompleter

typevars

currentClassFile

currentOwner

bp

CLASS_ATTRIBUTE

MEMBER_ATTRIBUTE

CLASS_OR_MEMBER_ATTRIBUTE

attributeReaders

currentLoc

Constructor Detail

ClassReader

Method Detail

instance

init

badClassFile

readEnclosingMethodAttr

enterTypevars

enterTypevars

defineClass

enterClass

enterClass

enterClass

loadClass

packageExists

enterPackage

enterPackage

includeClassFile

preferredFileObject

getPackageFileKinds

extraFileActions