Package org.apache.sshd.common.util

Class EventListenerUtils

  • public final class EventListenerUtils
extends java.lang.Object

    • Field Summary

      Fields 
      Modifier and Type Field Description
      static java.util.Comparator<java.util.EventListener> LISTENER_INSTANCE_COMPARATOR
      A special "comparator" whose only purpose is to ensure there are no same references in a listener's set - to be used in conjunction with a TreeSet as its comparator

    • Constructor Summary

      Constructors 
      Modifier Constructor Description
      private EventListenerUtils()  

    • Method Summary

      All Methods Static Methods Concrete Methods 
      Modifier and Type Method Description
      static <T extends SshdEventListener>
      T      		 proxyWrapper​(java.lang.Class<T> listenerType, java.lang.ClassLoader loader, java.lang.Iterable<? extends T> listeners)
      Provides proxy wrapper around an Iterable container of listener interface implementation.
      static <T extends SshdEventListener>
      T      		 proxyWrapper​(java.lang.Class<T> listenerType, java.lang.Iterable<? extends T> listeners)
      Provides proxy wrapper around an Iterable container of listener interface implementation.
      static <L extends SshdEventListener>
      java.util.Set<L>      		 synchronizedListenersSet()  
      static <L extends SshdEventListener>
      java.util.Set<L>      		 synchronizedListenersSet​(java.util.Collection<? extends L> listeners)  

      • Methods inherited from class java.lang.Object

        clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • LISTENER_INSTANCE_COMPARATOR

        public static final java.util.Comparator<java.util.EventListener> LISTENER_INSTANCE_COMPARATOR
        A special "comparator" whose only purpose is to ensure there are no same references in a listener's set - to be used in conjunction with a TreeSet as its comparator

    • Constructor Detail

      • EventListenerUtils

        private EventListenerUtils()

    • Method Detail

      • synchronizedListenersSet

        public static <L extends SshdEventListener> java.util.Set<L> synchronizedListenersSet​(java.util.Collection<? extends L> listeners)
        Type Parameters:
        L - Type of SshdEventListener contained in the set
        Parameters:
        listeners - The listeners to pre-add to the create set - ignored if (@code null}/empty
        Returns:
        A (synchronized) Set for containing the listeners ensuring that if same listener instance is added repeatedly only one instance is actually contained

      • synchronizedListenersSet

        public static <L extends SshdEventListener> java.util.Set<L> synchronizedListenersSet()
        Type Parameters:
        L - Type of SshdEventListener contained in the set
        Returns:
        A (synchronized) Set for containing the listeners ensuring that if same listener instance is added repeatedly only one instance is actually contained
        See Also:
        LISTENER_INSTANCE_COMPARATOR

      • proxyWrapper

        public static <T extends SshdEventListener> T proxyWrapper​(java.lang.Class<T> listenerType,
                                                           java.lang.Iterable<? extends T> listeners)
        Provides proxy wrapper around an Iterable container of listener interface implementation. Note: a listener interface is one whose invoked methods return only void.
        Type Parameters:
        T - Generic listener type
        Parameters:
        listenerType - The expected listener interface
        listeners - An Iterable container of listeners to be invoked.

        Note(s):

        • The invocation order is same as the Iterable container

        • If any of the invoked listener methods throws an exception, the rest of the listener are not invoked and the exception is propagated to the caller

        • It is up to the caller to ensure that the container does not change while the proxy is invoked

        Returns:
        A proxy wrapper implementing the same interface, but delegating the calls to the container
        See Also:
        proxyWrapper(Class, ClassLoader, Iterable)

      • proxyWrapper

        public static <T extends SshdEventListener> T proxyWrapper​(java.lang.Class<T> listenerType,
                                                           java.lang.ClassLoader loader,
                                                           java.lang.Iterable<? extends T> listeners)
        Provides proxy wrapper around an Iterable container of listener interface implementation. Note: a listener interface is one whose invoked methods return only void.
        Type Parameters:
        T - Generic SshdEventListener type
        Parameters:
        listenerType - The expected listener interface
        loader - The ClassLoader to use for the proxy
        listeners - An Iterable container of listeners to be invoked.

        Note(s):

        • The invocation order is same as the Iterable container

        • If any of the invoked listener methods throws an exception, the rest of the listener are not invoked and the exception is propagated to the caller

        • It is up to the caller to ensure that the container does not change while the proxy is invoked

        Returns:
        A proxy wrapper implementing the same interface, but delegating the calls to the container
        Throws:
        java.lang.IllegalArgumentException - if listenerType is not an interface or a null container has been provided
        See Also:
        proxyWrapper(Class, ClassLoader, Iterable)