org.apache.sshd.common.util

Class EventListenerUtils

java.lang.Object

org.apache.sshd.common.util.EventListenerUtils

public final class EventListenerUtils
extends Object

Author:

Apache MINA SSHD Project

Field Summary

Fields

Modifier and Type	Field and Description
static Comparator<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

Method Summary

Modifier and Type	Method and Description
static <T extends SshdEventListener> T	proxyWrapper(Class<T> listenerType, ClassLoader loader, Iterable<? extends T> listeners) Provides proxy wrapper around an Iterable container of listener interface implementation.
static <T extends SshdEventListener> T	proxyWrapper(Class<T> listenerType, Iterable<? extends T> listeners) Provides proxy wrapper around an Iterable container of listener interface implementation.
static <L extends SshdEventListener> Set<L>	synchronizedListenersSet()
static <L extends SshdEventListener> Set<L>	synchronizedListenersSet(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 Comparator<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

Method Detail

synchronizedListenersSet

public static <L extends SshdEventListener> Set<L> synchronizedListenersSet(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> 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(Class<T> listenerType,
                                                           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(Class<T> listenerType,
                                                           ClassLoader loader,
                                                           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:

IllegalArgumentException - if listenerType is not an interface or a null container has been provided

See Also:

proxyWrapper(Class, ClassLoader, Iterable)