Module openj9.dtfj
Package com.ibm.dtfj.java

Interface JavaClassLoader

All Known Implementing Classes:
DTFJJavaClassloader, JavaClassLoader, JCJavaClassLoader
public interface JavaClassLoader

Represents an internal ClassLoader structure within a Java VM instance. For most ClassLoaders there is a corresponding java.lang.ClassLoader object within with JavaRuntime. For primordial class loaders such as the bootstrap class loader, there may or may not be a corresponding java.lang.ClassLoader instance.

Since Java does not define any strict inheritance structure between class loaders, there are no APIs for inspecting 'child' or 'parent' class loaders. This information may be inferred by inspecting the corresponding java.lang.ClassLoader instance.

See Also:

  • Method Summary

    Modifier and Type
    Method
    Description
    boolean
    equals(Object obj)
    Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison.
    JavaClass
    findClass(String name)
    Find a named class within this class loader.
    Iterator
    getCachedClasses()
    When a ClassLoader successfully delegates a findClass() request to another ClassLoader, the result of the delegation must be cached within the internal structure so that the VM does not make repeated requests for the same class.
    Iterator
    getDefinedClasses()
    Get the set of classes which are defined in this JavaClassLoader.
    JavaObject
    getObject()
    Get the java.lang.ClassLoader instance associated with this class loader.
    int
    hashCode()
    Answers an integer hash code for the receiver.

  • Method Details

    • getDefinedClasses

      Iterator getDefinedClasses()
      Get the set of classes which are defined in this JavaClassLoader.
      Returns:
      an iterator over the collection of classes which are defined in this JavaClassLoader
      See Also:

    • getCachedClasses

      Iterator getCachedClasses()
      When a ClassLoader successfully delegates a findClass() request to another ClassLoader, the result of the delegation must be cached within the internal structure so that the VM does not make repeated requests for the same class.
      Returns:
      an iterator over the collection of classes which are defined in this JavaClassLoader or which were found by delegation to other JavaClassLoaders
      See Also:

    • findClass

      JavaClass findClass(String name) throws CorruptDataException
      Find a named class within this class loader. The class may have been defined in this class loader, or this class loader may have delegated the load to another class loader and cached the result.
      Parameters:
      name - of the class to find. Packages should be separated by '/' instead of '.'
      Returns:
      the JavaClass instance, or null if it is not found
      Throws:
      CorruptDataException

    • getObject

      JavaObject getObject() throws CorruptDataException
      Get the java.lang.ClassLoader instance associated with this class loader.
      Returns:
      a JavaObject representing the java.lang.ClassLoader instance associated with this class loader, or null if there is no Java class loader associated with this low-level class loader.
      Throws:
      CorruptDataException
      See Also:

    • equals

      boolean equals(Object obj)
      Description copied from class: java.lang.Object
      Compares the argument to the receiver, and answers true if they represent the same object using a class specific comparison. The implementation in Object answers true only if the argument is the exact same object as the receiver (==).
      Overrides:
      equals in class Object
      Parameters:
      obj -
      Returns:
      True if the given object refers to the same Java Class Loader in the image
      See Also:

    • hashCode

      int hashCode()
      Description copied from class: java.lang.Object
      Answers an integer hash code for the receiver. Any two objects which answer true when passed to .equals must answer the same value for this method.
      Overrides:
      hashCode in class Object
      Returns:
      the receiver's hash.
      See Also: