javax.management.loading: public interface: ClassLoaderRepository

javax.management.loading
public interface: ClassLoaderRepository [javadoc | source]

Instances of this interface are used to keep the list of ClassLoaders registered in an MBean Server. They provide the necessary methods to load classes using the registered ClassLoaders.

The first ClassLoader in a ClassLoaderRepository is always the MBean Server's own ClassLoader.

When an MBean is registered in an MBean Server, if it is of a subclass of java.lang.ClassLoader and if it does not implement the interface PrivateClassLoader , it is added to the end of the MBean Server's ClassLoaderRepository. If it is subsequently unregistered from the MBean Server, it is removed from the ClassLoaderRepository.

The order of MBeans in the ClassLoaderRepository is significant. For any two MBeans X and Y in the ClassLoaderRepository, X must appear before Y if the registration of X was completed before the registration of Y started. If X and Y were registered concurrently, their order is indeterminate. The registration of an MBean corresponds to the call to MBeanServer#registerMBean or one of the MBeanServer .createMBean methods.

Also see:

javax.management.MBeanServerFactory

since: 1.5 -

Method from javax.management.loading.ClassLoaderRepository Summary:
loadClass, loadClassBefore, loadClassWithout

Method from javax.management.loading.ClassLoaderRepository Detail:
public Class<?> loadClass(String className) throws ClassNotFoundException Load the given class name through the list of class loaders. Each ClassLoader in turn from the ClassLoaderRepository is asked to load the class via its ClassLoader#loadClass(String) method. If it successfully returns a Class object, that is the result of this method. If it throws a ClassNotFoundException , the search continues with the next ClassLoader. If it throws another exception, the exception is propagated from this method. If the end of the list is reached, a ClassNotFoundException is thrown.
public Class<?> loadClassBefore(ClassLoader stop, String className) throws ClassNotFoundException Load the given class name through the list of class loaders, stopping at the given one. Each ClassLoader in turn from the ClassLoaderRepository is asked to load the class via its ClassLoader#loadClass(String) method. If it successfully returns a Class object, that is the result of this method. If it throws a ClassNotFoundException , the search continues with the next ClassLoader. If it throws another exception, the exception is propagated from this method. If the search reaches `stop` or the end of the list, a ClassNotFoundException is thrown. Typically this method is called from the loadClass method of `stop`, to consult loaders that appear before it in the `ClassLoaderRepository`. By stopping the search as soon as `stop` is reached, a potential deadlock with concurrent class loading is avoided.
public Class<?> loadClassWithout(ClassLoader exclude, String className) throws ClassNotFoundException Load the given class name through the list of class loaders, excluding the given one. Each ClassLoader in turn from the ClassLoaderRepository, except `exclude`, is asked to load the class via its ClassLoader#loadClass(String) method. If it successfully returns a Class object, that is the result of this method. If it throws a ClassNotFoundException , the search continues with the next ClassLoader. If it throws another exception, the exception is propagated from this method. If the end of the list is reached, a ClassNotFoundException is thrown. Be aware that if a ClassLoader in the ClassLoaderRepository calls this method from its loadClass method, it exposes itself to a deadlock if another ClassLoader in the ClassLoaderRepository does the same thing at the same time. The #loadClassBefore method is recommended to avoid the risk of deadlock.

Method from javax.management.loading.ClassLoaderRepository Detail:

 public Class<?> loadClass(String className) throws ClassNotFoundExceptionLoad the given class name through the list of class loaders.
Each ClassLoader in turn from the ClassLoaderRepository is
asked to load the class via its ClassLoader#loadClass(String)  method.  If it successfully
returns a Class  object, that is the result of this
method.  If it throws a ClassNotFoundException , the
search continues with the next ClassLoader.  If it throws
another exception, the exception is propagated from this
method.  If the end of the list is reached, a ClassNotFoundException  is thrown.

 public Class<?> loadClassBefore(ClassLoader stop,
    String className) throws ClassNotFoundExceptionLoad the given class name through the list of class loaders,
stopping at the given one.  Each ClassLoader in turn from the
ClassLoaderRepository is asked to load the class via its ClassLoader#loadClass(String)  method.  If it successfully
returns a Class  object, that is the result of this
method.  If it throws a ClassNotFoundException , the
search continues with the next ClassLoader.  If it throws
another exception, the exception is propagated from this
method.  If the search reaches stop or the end of
the list, a ClassNotFoundException  is thrown.

Typically this method is called from the  loadClass  method of
stop, to consult loaders that appear before it
in the ClassLoaderRepository.  By stopping the
search as soon as stop is reached, a potential
deadlock with concurrent class loading is avoided.

 public Class<?> loadClassWithout(ClassLoader exclude,
    String className) throws ClassNotFoundExceptionLoad the given class name through the list of class loaders,
excluding the given one.  Each ClassLoader in turn from the
ClassLoaderRepository, except exclude, is asked to
load the class via its ClassLoader#loadClass(String) 
method.  If it successfully returns a Class  object,
that is the result of this method.  If it throws a ClassNotFoundException , the search continues with the next
ClassLoader.  If it throws another exception, the exception is
propagated from this method.  If the end of the list is
reached, a ClassNotFoundException  is thrown.

Be aware that if a ClassLoader in the ClassLoaderRepository
calls this method from its loadClass  method, it exposes itself to a deadlock if another
ClassLoader in the ClassLoaderRepository does the same thing at
the same time.  The #loadClassBefore  method is
recommended to avoid the risk of deadlock.