ClassLoaderReference (Java SE 22 & JDK 22)
Description: declaration: module: jdk.jdi, package: com.sun.jdi, interface: ClassLoaderReference
Keywords: com.sun.jdi.ClassLoaderReference interface

Module jdk.jdi
Package com.sun.jdi

# 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:
  - `ObjectReference`

- ## Field Summary

  ### Fields declared in interface com.sun.jdi.ObjectReference

  `INVOKE_NONVIRTUAL, INVOKE_SINGLE_THREADED`

- ## 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 com.sun.jdi.Mirror

  `toString, virtualMachine`

  ### Methods declared in interface com.sun.jdi.ObjectReference

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

  ### Methods declared in interface com.sun.jdi.Value

  `type`

- ## 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 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:
      - JVM TI GetClassLoaderClasses