@Exported public interface ReferenceType extends Type, Comparable<ReferenceType>, Accessible
ClassType
for classes,
InterfaceType
for interfaces, and
ArrayType
for arrays.
Note that primitive classes (for example, the
reflected type
of
Integer.TYPE
)
are represented as ClassType.
The VM creates Class objects for all three, so from the VM perspective,
each ReferenceType maps to a distinct Class object.
ReferenceTypes can
be obtained by querying a particular ObjectReference
for its
type or by getting a list of all reference types from the
VirtualMachine
.
ReferenceType provides access to static type information such as methods and fields and provides access to dynamic type information such as the corresponding Class object and the classloader.
Any method on ReferenceType
which directly or
indirectly takes ReferenceType
as an parameter may throw
VMDisconnectedException
if the target VM is
disconnected and the VMDisconnectEvent
has been or is
available to be read from the EventQueue
.
Any method on ReferenceType
which directly or
indirectly takes ReferenceType
as an parameter may throw
VMOutOfMemoryException
if the target VM has run out of memory.
Any method on ReferenceType
or which directly or indirectly takes
ReferenceType
as parameter may throw
ObjectCollectedException
if the mirrored type has been unloaded.
ObjectReference
,
ObjectReference.referenceType()
,
VirtualMachine
,
VirtualMachine.allClasses()
Modifier and Type | Method and Description |
---|---|
List<Field> |
allFields()
Returns a list containing each
Field declared in this type,
and its superclasses, implemented interfaces, and/or superinterfaces. |
List<Location> |
allLineLocations()
Returns a list containing a
Location object
for each executable source line in this reference type. |
List<Location> |
allLineLocations(String stratum,
String sourceName)
Returns a list containing a
Location object
for each executable source line in this reference type. |
List<Method> |
allMethods()
Returns a list containing each
Method declared in this type,
and its superclasses, implemented interfaces, and/or superinterfaces. |
List<String> |
availableStrata()
Return the available strata for this reference type.
|
ClassLoaderReference |
classLoader()
Gets the classloader object which loaded the class corresponding
to this type.
|
ClassObjectReference |
classObject()
Returns the class object that corresponds to this type in the
target VM.
|
byte[] |
constantPool()
Returns the raw bytes of the constant pool in the format of the
constant_pool item of the Class File Format in the Java Virtual
Machine Specification.
|
int |
constantPoolCount()
Returns the number of entries in the constant pool plus one.
|
String |
defaultStratum()
Returns the default stratum for this reference type.
|
boolean |
equals(Object obj)
Compares the specified Object with this ReferenceType for equality.
|
boolean |
failedToInitialize()
Determines if initialization failed for this class.
|
Field |
fieldByName(String fieldName)
Finds the visible
Field with the given
non-ambiguous name. |
List<Field> |
fields()
Returns a list containing each
Field declared in this type. |
String |
genericSignature()
Gets the generic signature for this type if there is one.
|
Value |
getValue(Field field)
|
Map<Field,Value> |
getValues(List<? extends Field> fields)
|
int |
hashCode()
Returns the hash code value for this ObjectReference.
|
List<ObjectReference> |
instances(long maxInstances)
Returns instances of this ReferenceType.
|
boolean |
isAbstract()
Determines if this type was declared abstract.
|
boolean |
isFinal()
Determines if this type was declared final.
|
boolean |
isInitialized()
Determines if this type has been initialized.
|
boolean |
isPrepared()
Determines if this type has been prepared.
|
boolean |
isStatic()
Determines if this type was declared static.
|
boolean |
isVerified()
Determines if this type has been verified.
|
List<Location> |
locationsOfLine(int lineNumber)
Returns a List containing all
Location objects
that map to the given line number. |
List<Location> |
locationsOfLine(String stratum,
String sourceName,
int lineNumber)
Returns a List containing all
Location objects
that map to the given line number. |
int |
majorVersion()
Returns the class major version number, as defined in the class file format
of the Java Virtual Machine Specification.
|
List<Method> |
methods()
Returns a list containing each
Method declared
directly in this type. |
List<Method> |
methodsByName(String name)
Returns a List containing each visible
Method that
has the given name. |
List<Method> |
methodsByName(String name,
String signature)
Returns a List containing each visible
Method that
has the given name and signature. |
int |
minorVersion()
Returns the class minor version number, as defined in the class file format
of the Java Virtual Machine Specification.
|
String |
name()
Gets the fully qualified name of this type.
|
List<ReferenceType> |
nestedTypes()
Returns a List containing
ReferenceType objects that are
declared within this type and are currently loaded into the Virtual
Machine. |
String |
sourceDebugExtension()
Get the source debug extension of this type.
|
String |
sourceName()
Gets an identifying name for the source corresponding to the
declaration of this type.
|
List<String> |
sourceNames(String stratum)
Gets the identifying names for all the source corresponding to the
declaration of this type.
|
List<String> |
sourcePaths(String stratum)
Gets the paths to the source corresponding to the
declaration of this type.
|
List<Field> |
visibleFields()
Returns a list containing each unhidden and unambiguous
Field
in this type. |
List<Method> |
visibleMethods()
Returns a list containing each
Method
declared or inherited by this type. |
toString, virtualMachine
compareTo
isPackagePrivate, isPrivate, isProtected, isPublic, modifiers
String name()
For primitive classes
the returned name is the name of the corresponding primitive
type; for example, "int" is returned as the name of the class
represented by Integer.TYPE
.
String genericSignature()
null
if there is no generic signature.ClassLoaderReference classLoader()
ClassLoaderReference
which mirrors the classloader,
or null
if the class was loaded through the bootstrap class
loader.String sourceName() throws AbsentInformationException
The returned name is dependent on VM's default stratum
(VirtualMachine.getDefaultStratum()
).
In the reference implementation, when using the base stratum,
the returned string is the
unqualified name of the source file containing the declaration
of this type. In other strata the returned source name is
the first source name for that stratum. Since other languages
may have more than one source name for a reference type,
the use of Location.sourceName()
or
sourceNames(String)
is preferred.
For arrays (ArrayType
) and primitive classes,
AbsentInformationException is always thrown.
AbsentInformationException
- if the source name is not
knownList<String> sourceNames(String stratum) throws AbsentInformationException
The returned names are for the specified stratum
(see Location
for a description of strata).
In the reference implementation, when using the Java
programming language stratum,
the returned List contains one element: a String which is the
unqualified name of the source file containing the declaration
of this type. In other strata the returned source names are
all the source names defined for that stratum.
stratum
- The stratum to retrieve information from
or null
for the declaring type's
default stratum.AbsentInformationException
- if the source names are not
known.
For arrays (ArrayType
) and primitive classes,
AbsentInformationException is always thrown.
List<String> sourcePaths(String stratum) throws AbsentInformationException
The returned paths are for the specified stratum
(see Location
for a description of strata).
In the reference implementation, for strata which
do not explicitly specify source path (the Java
programming language stratum never does), the returned
strings are the sourceNames(String)
prefixed by
the package name of this ReferenceType
converted to a platform dependent path.
For example, on a Windows platform,
java.lang.Thread
would return a List containing one element:
"java\lang\Thread.java"
.
stratum
- The stratum to retrieve information from
or null
for the declaring type's
default stratum.AbsentInformationException
- if the source names are not
known.
For arrays (ArrayType
) and primitive classes,
AbsentInformationException is always thrown.
String sourceDebugExtension() throws AbsentInformationException
Not all target virtual machines support this operation.
Use
canGetSourceDebugExtension()
to determine if the operation is supported.
AbsentInformationException
- if the extension is not
specifiedUnsupportedOperationException
- if
the target virtual machine does not support this
operation - see
canGetSourceDebugExtension()
,boolean isStatic()
false
is returned
for any package-level type, array type, or primitive class.true
if this type is static; false otherwise.boolean isAbstract()
For arrays (ArrayType
) and primitive classes,
the return value is undefined.
true
if this type is abstract; false otherwise.boolean isFinal()
For arrays (ArrayType
) and primitive classes,
the return value is always true.
true
if this type is final; false otherwise.boolean isPrepared()
For arrays (ArrayType
) and primitive classes,
the return value is undefined.
true
if this type is prepared; false otherwise.boolean isVerified()
For arrays (ArrayType
) and primitive classes,
the return value is undefined.
true
if this type is verified; false otherwise.boolean isInitialized()
InterfaceType
, this method always returns the
same value as isPrepared()
.
For arrays (ArrayType
) and primitive classes,
the return value is undefined.
true
if this type is initialized; false otherwise.boolean failedToInitialize()
For arrays (ArrayType
) and primitive classes,
the return value is undefined.
true
if initialization was attempted and
failed; false otherwise.List<Field> fields()
Field
declared in this type.
Inherited fields are not included. Any synthetic fields created
by the compiler are included in the list.
For arrays (ArrayType
) and primitive classes, the returned
list is always empty.
Field
objects; the list has length 0
if no fields exist.ClassNotPreparedException
- if this class not yet been
prepared.List<Field> visibleFields()
Field
in this type.
Each field that can be accessed from the class
or its instances with its simple name is included. Fields that
are ambiguously multiply inherited or fields that are hidden by
fields with the same name in a more recently inherited class
cannot be accessed
by their simple names and are not included in the returned
list. All other inherited fields are included.
See JLS section 8.3 for details.
For arrays (ArrayType
) and primitive classes, the returned
list is always empty.
Field
objects; the list has length
0 if no visible fields exist.ClassNotPreparedException
- if this class not yet been
prepared.List<Field> allFields()
Field
declared in this type,
and its superclasses, implemented interfaces, and/or superinterfaces.
All declared and inherited
fields are included, regardless of whether they are hidden or
multiply inherited.
For arrays (ArrayType
) and primitive classes, the returned
list is always empty.
Field
objects; the list has length
0 if no fields exist.ClassNotPreparedException
- if this class not yet been
prepared.Field fieldByName(String fieldName)
Field
with the given
non-ambiguous name. This method follows the
inheritance rules specified in the JLS (8.3.3) to determine
visibility.
For arrays (ArrayType
) and primitive classes, the returned
value is always null.
fieldName
- a String containing the name of desired field.Field
object which mirrors the found field, or
null if there is no field with the given name or if the given
name is ambiguous.ClassNotPreparedException
- if this class not yet been
prepared.List<Method> methods()
Method
declared
directly in this type.
Inherited methods are not included. Constructors,
the initialization method if any, and any synthetic methods created
by the compiler are included in the list.
For arrays (ArrayType
) and primitive classes, the returned
list is always empty.
Method
objects; the list has length 0
if no methods exist.ClassNotPreparedException
- if this class not yet been
prepared.List<Method> visibleMethods()
Method
declared or inherited by this type. Methods from superclasses
or superinterfaces that that have been hidden or overridden
are not included.
Note that despite this exclusion, multiple inherited methods
with the same signature can be present in the returned list, but
at most one can be a member of a ClassType
.
See JLS section 8.4.6 for details.
For arrays (ArrayType
) and primitive classes, the returned
list is always empty.
Method
objects; the list has length
0 if no visible methods exist.ClassNotPreparedException
- if this class not yet been
prepared.List<Method> allMethods()
Method
declared in this type,
and its superclasses, implemented interfaces, and/or superinterfaces.
All declared and inherited
methods are included, regardless of whether they are hidden or
overridden.
For arrays (ArrayType
) and primitive classes, the returned
list is always empty.
Method
objects; the list has length
0 if no methods exist.ClassNotPreparedException
- if this class not yet been
prepared.List<Method> methodsByName(String name)
Method
that
has the given name. This is most commonly used to
find overloaded methods.
Overridden and hidden methods are not included. See JLS (8.4.6) for details.
For arrays (ArrayType
) and primitive classes, the returned
list is always empty.
name
- the name of the method to find.Method
objects that match the given
name; the list has length 0 if no matching methods are found.ClassNotPreparedException
- if this class not yet been
prepared.List<Method> methodsByName(String name, String signature)
Method
that
has the given name and signature.
The signature string is the
JNI signature for the target method:
()V
([Ljava/lang/String;)V
(IIII)Z
At most one method in the list is a concrete method and a
component of ClassType
; any other methods in the list
are abstract. Use ClassType.concreteMethodByName(java.lang.String, java.lang.String)
to
retrieve only the matching concrete method.
For arrays (ArrayType
) and primitive classes, the returned
list is always empty.
name
- the name of the method to find.signature
- the signature of the method to findMethod
objects that match the given
name and signature; the list has length 0 if no matching methods
are found.ClassNotPreparedException
- if this class not yet been
prepared.List<ReferenceType> nestedTypes()
ReferenceType
objects that are
declared within this type and are currently loaded into the Virtual
Machine. Both static nested types and non-static nested
types (that is, inner types) are included. Local inner types
(declared within a code block somewhere in this reference type) are
also included in the returned list.
For arrays (ArrayType
) and primitive classes, the returned
list is always empty.
ReferenceType
objects; the list
has 0 length if there are no nested types.Value getValue(Field field)
Value
of a given static Field
in this type.
The Field must be valid for this type;
that is, it must be declared in this type, a superclass, a
superinterface, or an implemented interface.field
- the field containing the requested valueValue
of the instance field.IllegalArgumentException
- if the field is not valid for
this object's class.Map<Field,Value> getValues(List<? extends Field> fields)
Value
of each
static Field
in the given list.
The Fields must be valid for this type;
that is, they must be declared in this type, a superclass, a
superinterface, or an implemented interface.fields
- a list of Field
objects containing the
requested values.Field
objects with
their Value
.IllegalArgumentException
- if any field is not valid for
this object's class.VMMismatchException
- if a Mirror
argument and this mirror
do not belong to the same VirtualMachine
.ClassObjectReference classObject()
ClassObjectReference
for this reference type
in the target VM.List<Location> allLineLocations() throws AbsentInformationException
Location
object
for each executable source line in this reference type.
This method is equivalent to
allLineLocations(vm.getDefaultStratum(),null)
-
see allLineLocations(String,String)
for more information.
AbsentInformationException
- if there is no line
number information for this class and there are non-native,
non-abstract executable members of this class.ClassNotPreparedException
- if this class not yet
been prepared.List<Location> allLineLocations(String stratum, String sourceName) throws AbsentInformationException
Location
object
for each executable source line in this reference type.
Each location maps a source line to a range of code
indices.
The beginning of the range can be determined through
Location.codeIndex()
. The returned list may contain
multiple locations for a particular line number, if the
compiler and/or VM has mapped that line to two or more
disjoint code index ranges. Note that it is possible for
the same source line to represent different code index
ranges in different methods.
For arrays (ArrayType
) and primitive classes, the
returned list is always empty. For interfaces (InterfaceType
), the returned list will be non-empty only
if the interface has executable code in its class
initialization.
Returned list is for the specified stratum
(see Location
for a description of strata).
stratum
- The stratum to retrieve information from
or null
for the defaultStratum()
.sourceName
- Return locations only within this
source file or null
to return locations.Location
objects.AbsentInformationException
- if there is no line
number information for this class and there are non-native,
non-abstract executable members of this class.
Or if sourceName is non-null
and source name information is not present.ClassNotPreparedException
- if this class not yet
been prepared.List<Location> locationsOfLine(int lineNumber) throws AbsentInformationException
Location
objects
that map to the given line number.
This method is equivalent to
locationsOfLine(vm.getDefaultStratum(), null,
lineNumber)
-
see locationsOfLine(java.lang.String,java.lang.String,int)
for more information.
lineNumber
- the line numberLocation
objects that map to
the given line.AbsentInformationException
- if there is no line
number information for this class.ClassNotPreparedException
- if this class not yet
been prepared.VirtualMachine.getDefaultStratum()
List<Location> locationsOfLine(String stratum, String sourceName, int lineNumber) throws AbsentInformationException
Location
objects
that map to the given line number.
For arrays (ArrayType
) and primitive classes, the
returned list is always empty.
For interfaces (InterfaceType
), the returned list
will be non-empty only if the interface has executable code
in its class initialization at the specified line number.
An empty list will be returned if there is no executable
code at the specified line number.
Returned list is for the specified stratum
(see Location
for a description of strata).
stratum
- the stratum to use for comparing line number
and source name, or null
to
use the defaultStratum()
.sourceName
- the source name containing the line
number, or null
to match
all source nameslineNumber
- the line numberLocation
objects that map
to the given line.AbsentInformationException
- if there is no line
number information for this class.
Or if sourceName is non-null
and source name information is not present.ClassNotPreparedException
- if this class not yet
been prepared.List<String> availableStrata()
See the Location
for a description of strata.
java.lang.String
, each
representing a stratumString defaultStratum()
"Java"
) will be returned.
See the Location
for a description of strata.
List<ObjectReference> instances(long maxInstances)
Not all target virtual machines support this operation.
Use VirtualMachine.canGetInstanceInfo()
to determine if the operation is supported.
maxInstances
- the maximum number of instances to return.
Must be non-negative. If zero, all instances are returned.ObjectReference
objects. If there are
no instances of this ReferenceType, a zero-length list is returned.UnsupportedOperationException
- if
the target virtual machine does not support this
operation - see
canGetInstanceInfo()
IllegalArgumentException
- if maxInstances is less
than zero.VirtualMachine.instanceCounts(List)
,
ObjectReference.referringObjects(long)
boolean equals(Object obj)
equals
in class Object
obj
- the reference object with which to compare.ReferenceType
, if the
ReferenceTypes belong to the same VM, and if they mirror classes
which correspond to the same instance of java.lang.Class in that VM.Object.hashCode()
,
HashMap
int hashCode()
hashCode
in class Object
Object.equals(java.lang.Object)
,
System.identityHashCode(java.lang.Object)
int majorVersion()
ArrayType
) and primitive classes,
the returned major version number value is zero.
Not all target virtual machines support this operation.
Use VirtualMachine.canGetClassFileVersion()
to determine if the operation is supported.UnsupportedOperationException
- if
the target virtual machine does not support this
operation - see
canGetClassFileVersion()
int minorVersion()
ArrayType
) and primitive classes,
the returned minor version number value is zero.
Not all target virtual machines support this operation.
Use VirtualMachine.canGetClassFileVersion()
to determine if the operation is supported.UnsupportedOperationException
- if
the target virtual machine does not support this
operation - see
canGetClassFileVersion()
int constantPoolCount()
ArrayType
) and primitive classes,
the returned constant pool count value is zero.
Not all target virtual machines support this operation.
Use VirtualMachine.canGetConstantPool()
to determine if the operation is supported.UnsupportedOperationException
- if
the target virtual machine does not support this
operation - see
canGetConstantPool()
constantPool()
byte[] constantPool()
ArrayType
) and primitive classes,
a zero length byte array is returned.
Not all target virtual machines support this operation.
Use VirtualMachine.canGetConstantPool()
to determine if the operation is supported.UnsupportedOperationException
- if
the target virtual machine does not support this
operation - see
canGetConstantPool()
constantPoolCount()
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