Interface ClassLoaderReference

All Superinterfaces:: Mirror, ObjectReference, Value

public interface ClassLoaderReference extends ObjectReference

A class loader object from the target VM. A ClassLoaderReference is an ObjectReference with additional access to classloader-specific information from the target VM. Instances ClassLoaderReference are obtained through calls to ReferenceType.classLoader()

Since:

1.3

See Also:

Field Summary

Fields declared in interface ObjectReference

INVOKE_NONVIRTUAL, INVOKE_SINGLE_THREADED

Modifier and Type	Field	Description
`static final int`	`INVOKE_NONVIRTUAL`	Perform non-virtual method invocation
`static final int`	`INVOKE_SINGLE_THREADED`	Perform method invocation with only the invoking thread resumed

Method Summary

Modifier and Type	Method	Description
`List<ReferenceType>`	`definedClasses()`	Returns a list of all classes defined by this class loader.
`List<ReferenceType>`	`visibleClasses()`	Returns a list of all classes which this class loader can find by name via `ClassLoader::loadClass`, `Class::forName` and bytecode linkage in the target VM.

Methods declared in interface Mirror

toString, virtualMachine

Modifier and Type	Method	Description
`String`	`toString()`	Returns a String describing this mirror
`VirtualMachine`	`virtualMachine()`	Gets the VirtualMachine to which this Mirror belongs.

Methods declared in interface ObjectReference

disableCollection, enableCollection, entryCount, equals, getValue, getValues, hashCode, invokeMethod, isCollected, owningThread, referenceType, referringObjects, setValue, uniqueID, waitingThreads

Modifier and Type	Method	Description
`void`	`disableCollection()`	Prevents garbage collection for this object.
`void`	`enableCollection()`	Permits garbage collection for this object.
`int`	`entryCount()`	Returns the number of times this object's monitor has been entered by the current owning thread if the owning thread is platform thread; Returns 0 if not owned by a platform thread.
`boolean`	`equals(Object obj)`	Compares the specified Object with this ObjectReference for equality.
`Value`	`getValue(Field sig)`	Gets the value of a given instance or static field in this object.
`Map<Field,Value>`	`getValues(List<? extends Field> fields)`	Gets the value of multiple instance and/or static fields in this object.
`int`	`hashCode()`	Returns the hash code value for this ObjectReference.
`Value`	`invokeMethod(ThreadReference thread, Method method, List<? extends Value> arguments, int options)`	Invokes the specified `Method` on this object in the target VM.
`boolean`	`isCollected()`	Determines if this object has been garbage collected in the target VM.
`ThreadReference`	`owningThread()`	Returns a `ThreadReference` for the platform thread, if any, which currently owns this object's monitor.
`ReferenceType`	`referenceType()`	Gets the `ReferenceType` that mirrors the type of this object.
`List<ObjectReference>`	`referringObjects(long maxReferrers)`	Returns objects that directly reference this object.
`void`	`setValue(Field field, Value value)`	Sets the value of a given instance or static field in this object.
`long`	`uniqueID()`	Returns a unique identifier for this ObjectReference.
`List<ThreadReference>`	`waitingThreads()`	Returns a List containing a `ThreadReference` for each platform thread currently waiting for this object's monitor.

Methods declared in interface Value

type

Modifier and Type	Method	Description
`Type`	`type()`	Returns the run-time type of this value.

Method Details

definedClasses

List<ReferenceType> definedClasses()

Returns a list of all classes defined by this class loader. No ordering of this list guaranteed. The returned list will include all reference types, including hidden classes or interfaces, loaded at least to the point of preparation, and types (like array) for which preparation is not defined.

Returns:: a List of ReferenceType objects mirroring types defined by this class loader. The list has length 0 if no types have been defined by this classloader.

visibleClasses

List<ReferenceType> visibleClasses()

Returns a list of all classes which this class loader can find by name via ClassLoader::loadClass, Class::forName and bytecode linkage in the target VM. That is, all classes for which this class loader has been recorded as an initiating loader.

Each class in the returned list was created by this class loader either by defining it directly or by delegation to another class loader (see JVMS Â§5.3).

The returned list does not include hidden classes or interfaces or array classes whose element type is a hidden class or interface. as they cannot be discovered by any class loader

The visible class list has useful properties with respect to the type namespace. A particular type name will occur at most once in the list. Each field or variable declared with that type name in a class defined by this class loader must be resolved to that single type.

No ordering of the returned list is guaranteed.

Note that unlike definedClasses() and VirtualMachine.allClasses(), some of the returned reference types may not be prepared. Attempts to perform some operations on unprepared reference types (e.g. fields()) will throw a ClassNotPreparedException. Use ReferenceType.isPrepared() to determine if a reference type is prepared.

Returns:

a List of ReferenceType objects mirroring classes which this class loader can find by name. The list has length 0 if no classes are visible to this classloader.

See Also:

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