JavaReference (Diagnostic Tool Framework for Java™)

```
public interface JavaReference
```
Represents a Java reference.

Field Summary

Fields
Modifier and Type	Field and Description
`static int`	`HEAP_ROOT_CLASSLOADER` Classloader heap root
`static int`	`HEAP_ROOT_FINALIZABLE_OBJ` Finalizable object heap root
`static int`	`HEAP_ROOT_JNI_GLOBAL` JNI global reference heap root
`static int`	`HEAP_ROOT_JNI_LOCAL` JNI local reference heap root
`static int`	`HEAP_ROOT_MONITOR` Monitor heap root
`static int`	`HEAP_ROOT_OTHER` Other heap root type
`static int`	`HEAP_ROOT_STACK_LOCAL` Stack local heap root
`static int`	`HEAP_ROOT_STRINGTABLE` Stringtable heap root
`static int`	`HEAP_ROOT_SYSTEM_CLASS` System class heap root
`static int`	`HEAP_ROOT_THREAD` Thread heap root
`static int`	`HEAP_ROOT_UNFINALIZED_OBJ` Unfinalized object heap root
`static int`	`HEAP_ROOT_UNKNOWN` Unknown heap root type
`static int`	`REACHABILITY_PHANTOM` Reachability of target object via this reference is Phantom
`static int`	`REACHABILITY_SOFT` Reachability of target object via this reference is Soft
`static int`	`REACHABILITY_STRONG` Reachability of target object via this reference is Strong
`static int`	`REACHABILITY_UNKNOWN` Reachability of target object via this reference is unknown
`static int`	`REACHABILITY_WEAK` Reachability of target object via this reference is Weak
`static int`	`REFERENCE_ARRAY_ELEMENT` Reference from an array to one of its elements
`static int`	`REFERENCE_ASSOCIATED_CLASS` Reference from a JavaObject representing a Class to the associated JavaClass
`static int`	`REFERENCE_CLASS` Reference from an object to its class
`static int`	`REFERENCE_CLASS_LOADER` Reference from a class to its class loader
`static int`	`REFERENCE_CLASS_OBJECT` Reference from a class to its java.lang.Class instance
`static int`	`REFERENCE_CONSTANT_POOL` Reference from a class to a resolved entry in the constant pool
`static int`	`REFERENCE_FIELD` Reference from an object to the value of one of its instance fields
`static int`	`REFERENCE_INTERFACE` Reference from a class to one of its interfaces
`static int`	`REFERENCE_LOADED_CLASS` Reference from a classloader object to its loaded classes
`static int`	`REFERENCE_PROTECTION_DOMAIN` Reference from a class to its protection domain
`static int`	`REFERENCE_SIGNERS` Reference from a class to its signers array
`static int`	`REFERENCE_STATIC_FIELD` Reference from a class to the value of one of its static fields
`static int`	`REFERENCE_SUPERCLASS` Reference from a class to its superclass
`static int`	`REFERENCE_UNKNOWN` Unknown reference type
`static int`	`REFERENCE_UNUSED_14`

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`String`	`getDescription()` Get a string describing the reference type.
`int`	`getReachability()` Get the reachability of the target object via this specific reference.
`int`	`getReferenceType()` Get the reference type, as defined in the JVMTI specification.
`int`	`getRootType()` Get the root type, as defined in the JVMTI specification.
`Object`	`getSource()` Get the source of this reference if available.
`Object`	`getTarget()` Get the object referred to by this reference.
`boolean`	`isClassReference()` Does this reference point to a class?
`boolean`	`isObjectReference()` Does this reference point to an object in the heap?

- Field Detail
  - HEAP_ROOT_UNKNOWN
```
static final int HEAP_ROOT_UNKNOWN
```
    Unknown heap root type
    
    See Also:
    
    Constant Field Values
  - HEAP_ROOT_JNI_GLOBAL
```
static final int HEAP_ROOT_JNI_GLOBAL
```
    JNI global reference heap root
    
    See Also:
    
    Constant Field Values
  - HEAP_ROOT_SYSTEM_CLASS
```
static final int HEAP_ROOT_SYSTEM_CLASS
```
    System class heap root
    
    See Also:
    
    Constant Field Values
  - HEAP_ROOT_MONITOR
```
static final int HEAP_ROOT_MONITOR
```
    Monitor heap root
    
    See Also:
    
    Constant Field Values
  - HEAP_ROOT_STACK_LOCAL
```
static final int HEAP_ROOT_STACK_LOCAL
```
    Stack local heap root
    
    See Also:
    
    Constant Field Values
  - HEAP_ROOT_JNI_LOCAL
```
static final int HEAP_ROOT_JNI_LOCAL
```
    JNI local reference heap root
    
    See Also:
    
    Constant Field Values
  - HEAP_ROOT_THREAD
```
static final int HEAP_ROOT_THREAD
```
    Thread heap root
    
    See Also:
    
    Constant Field Values
  - HEAP_ROOT_OTHER
```
static final int HEAP_ROOT_OTHER
```
    Other heap root type
    
    See Also:
    
    Constant Field Values
  - HEAP_ROOT_FINALIZABLE_OBJ
```
static final int HEAP_ROOT_FINALIZABLE_OBJ
```
    Finalizable object heap root
    
    See Also:
    
    Constant Field Values
  - HEAP_ROOT_UNFINALIZED_OBJ
```
static final int HEAP_ROOT_UNFINALIZED_OBJ
```
    Unfinalized object heap root
    
    See Also:
    
    Constant Field Values
  - HEAP_ROOT_CLASSLOADER
```
static final int HEAP_ROOT_CLASSLOADER
```
    Classloader heap root
    
    See Also:
    
    Constant Field Values
  - HEAP_ROOT_STRINGTABLE
```
static final int HEAP_ROOT_STRINGTABLE
```
    Stringtable heap root
    
    See Also:
    
    Constant Field Values
  - REFERENCE_UNKNOWN
```
static final int REFERENCE_UNKNOWN
```
    Unknown reference type
    
    See Also:
    
    Constant Field Values
  - REFERENCE_CLASS
```
static final int REFERENCE_CLASS
```
    Reference from an object to its class
    
    See Also:
    
    Constant Field Values
  - REFERENCE_FIELD
```
static final int REFERENCE_FIELD
```
    Reference from an object to the value of one of its instance fields
    
    See Also:
    
    Constant Field Values
  - REFERENCE_ARRAY_ELEMENT
```
static final int REFERENCE_ARRAY_ELEMENT
```
    Reference from an array to one of its elements
    
    See Also:
    
    Constant Field Values
  - REFERENCE_CLASS_LOADER
```
static final int REFERENCE_CLASS_LOADER
```
    Reference from a class to its class loader
    
    See Also:
    
    Constant Field Values
  - REFERENCE_SIGNERS
```
static final int REFERENCE_SIGNERS
```
    Reference from a class to its signers array
    
    See Also:
    
    Constant Field Values
  - REFERENCE_PROTECTION_DOMAIN
```
static final int REFERENCE_PROTECTION_DOMAIN
```
    Reference from a class to its protection domain
    
    See Also:
    
    Constant Field Values
  - REFERENCE_INTERFACE
```
static final int REFERENCE_INTERFACE
```
    Reference from a class to one of its interfaces
    
    See Also:
    
    Constant Field Values
  - REFERENCE_STATIC_FIELD
```
static final int REFERENCE_STATIC_FIELD
```
    Reference from a class to the value of one of its static fields
    
    See Also:
    
    Constant Field Values
  - REFERENCE_CONSTANT_POOL
```
static final int REFERENCE_CONSTANT_POOL
```
    Reference from a class to a resolved entry in the constant pool
    
    See Also:
    
    Constant Field Values
  - REFERENCE_SUPERCLASS
```
static final int REFERENCE_SUPERCLASS
```
    Reference from a class to its superclass
    
    See Also:
    
    Constant Field Values
  - REFERENCE_LOADED_CLASS
```
static final int REFERENCE_LOADED_CLASS
```
    Reference from a classloader object to its loaded classes
    
    See Also:
    
    Constant Field Values
  - REFERENCE_CLASS_OBJECT
```
static final int REFERENCE_CLASS_OBJECT
```
    Reference from a class to its java.lang.Class instance
    
    See Also:
    
    Constant Field Values
  - REFERENCE_ASSOCIATED_CLASS
```
static final int REFERENCE_ASSOCIATED_CLASS
```
    Reference from a JavaObject representing a Class to the associated JavaClass
    
    See Also:
    
    Constant Field Values
  - REFERENCE_UNUSED_14
```
static final int REFERENCE_UNUSED_14
```
    See Also:
    
    Constant Field Values
  - REACHABILITY_UNKNOWN
```
static final int REACHABILITY_UNKNOWN
```
    Reachability of target object via this reference is unknown
    
    See Also:
    
    Constant Field Values
  - REACHABILITY_STRONG
```
static final int REACHABILITY_STRONG
```
    Reachability of target object via this reference is Strong
    
    See Also:
    
    Constant Field Values
  - REACHABILITY_SOFT
```
static final int REACHABILITY_SOFT
```
    Reachability of target object via this reference is Soft
    
    See Also:
    
    Constant Field Values
  - REACHABILITY_WEAK
```
static final int REACHABILITY_WEAK
```
    Reachability of target object via this reference is Weak
    
    See Also:
    
    Constant Field Values
  - REACHABILITY_PHANTOM
```
static final int REACHABILITY_PHANTOM
```
    Reachability of target object via this reference is Phantom
    
    See Also:
    
    Constant Field Values
- Method Detail
  - getRootType
```
int getRootType()
         throws CorruptDataException
```
    Get the root type, as defined in the JVMTI specification.
    
    Returns:
    
    an integer representing the root type, see the HEAP_ROOT_ static fields.
    
    Throws:
    
    CorruptDataException
  - getReferenceType
```
int getReferenceType()
              throws CorruptDataException
```
    Get the reference type, as defined in the JVMTI specification.
    
    Returns:
    
    an integer representing the reference type, see the REFERENCE_ static fields.
    
    Throws:
    
    CorruptDataException
  - getReachability
```
int getReachability()
             throws CorruptDataException
```
    Get the reachability of the target object via this specific reference.
    
    Returns:
    
    an integer representing the reachability, see the REACHABILITY_ static fields.
    
    Throws:
    
    CorruptDataException
  - getDescription
```
String getDescription()
```
    Get a string describing the reference type. Implementers should not depend on the contents or identity of this string. e.g. JNI Weak global reference, Instance field 'MyClass.value', Constant pool string constant
    
    Returns:
    
    a String describing the reference type
  - isObjectReference
```
boolean isObjectReference()
                   throws DataUnavailable,
                          CorruptDataException
```
    Does this reference point to an object in the heap?
    
    Returns:
    
    true if the target of this root is an object
    
    Throws:
    
    DataUnavailable
    
    CorruptDataException
  - isClassReference
```
boolean isClassReference()
                  throws DataUnavailable,
                         CorruptDataException
```
    Does this reference point to a class?
    
    Returns:
    
    true if the target of this root is a class
    
    Throws:
    
    DataUnavailable
    
    CorruptDataException
  - getTarget
```
Object getTarget()
          throws DataUnavailable,
                 CorruptDataException
```
    Get the object referred to by this reference.
    
    Returns:
    
    a JavaObject or a JavaClass
    
    Throws:
    
    DataUnavailable
    
    CorruptDataException
  - getSource
```
Object getSource()
          throws DataUnavailable,
                 CorruptDataException
```
    Get the source of this reference if available.
    
    Returns:
    
    a JavaClass, JavaObject, JavaStackFrame or null if unknown
    
    Throws:
    
    DataUnavailable
    
    CorruptDataException

Interface JavaReference

Field Summary

Method Summary

Field Detail

HEAP_ROOT_UNKNOWN

HEAP_ROOT_JNI_GLOBAL

HEAP_ROOT_SYSTEM_CLASS

HEAP_ROOT_MONITOR

HEAP_ROOT_STACK_LOCAL

HEAP_ROOT_JNI_LOCAL

HEAP_ROOT_THREAD

HEAP_ROOT_OTHER

HEAP_ROOT_FINALIZABLE_OBJ

HEAP_ROOT_UNFINALIZED_OBJ

HEAP_ROOT_CLASSLOADER

HEAP_ROOT_STRINGTABLE

REFERENCE_UNKNOWN

REFERENCE_CLASS

REFERENCE_FIELD

REFERENCE_ARRAY_ELEMENT

REFERENCE_CLASS_LOADER

REFERENCE_SIGNERS

REFERENCE_PROTECTION_DOMAIN

REFERENCE_INTERFACE

REFERENCE_STATIC_FIELD

REFERENCE_CONSTANT_POOL

REFERENCE_SUPERCLASS

REFERENCE_LOADED_CLASS

REFERENCE_CLASS_OBJECT

REFERENCE_ASSOCIATED_CLASS

REFERENCE_UNUSED_14

REACHABILITY_UNKNOWN

REACHABILITY_STRONG

REACHABILITY_SOFT

REACHABILITY_WEAK

REACHABILITY_PHANTOM

Method Detail

getRootType

getReferenceType

getReachability

getDescription

isObjectReference

isClassReference

getTarget

getSource