TooManyListenersException

AI-generated Key Takeaways

• TooManyListenersException signals that only one listener can be registered at a time for a specific event source, enforcing a unicast model.

• It's part of the Java Event model and indicates a unicast event listener registration pattern instead of the typical multicast.

• This exception is thrown when attempting to add a listener to an event source that already has one registered.

• Two constructors are available: one with no detail message and one with a custom message to describe the exception.

public class TooManyListenersException extends Exception

The TooManyListenersException Exception is used as part of the Java Event model to annotate and implement a unicast special case of a multicast Event Source.

The presence of a "throws TooManyListenersException" clause on any given concrete implementation of the normally multicast "void addXyzEventListener" event listener registration pattern is used to annotate that interface as implementing a unicast Listener special case, that is, that one and only one Listener may be registered on the particular event listener source concurrently.

See Also

• EventObject
• EventListener

Public Constructor Summary

	TooManyListenersException() Constructs a TooManyListenersException with no detail message.
	TooManyListenersException(String s) Constructs a TooManyListenersException with the specified detail message.

Inherited Method Summary

From class java.lang.Throwable

synchronized final void	addSuppressed(Throwable exception) Appends the specified exception to the exceptions that were suppressed in order to deliver this exception.
synchronized Throwable	fillInStackTrace() Fills in the execution stack trace.
synchronized Throwable	getCause() Returns the cause of this throwable or null if the cause is nonexistent or unknown.
String	getLocalizedMessage() Creates a localized description of this throwable.
String	getMessage() Returns the detail message string of this throwable.
StackTraceElement[]	getStackTrace() Provides programmatic access to the stack trace information printed by printStackTrace().
synchronized final Throwable[]	getSuppressed() Returns an array containing all of the exceptions that were suppressed, typically by the try-with-resources statement, in order to deliver this exception.
synchronized Throwable	initCause(Throwable cause) Initializes the cause of this throwable to the specified value.
void	printStackTrace() Prints this throwable and its backtrace to the standard error stream.
void	printStackTrace(PrintWriter s) Prints this throwable and its backtrace to the specified print writer.
void	printStackTrace(PrintStream s) Prints this throwable and its backtrace to the specified print stream.
void	setStackTrace(StackTraceElement[] stackTrace) Sets the stack trace elements that will be returned by getStackTrace() and printed by printStackTrace() and related methods.
String	toString() Returns a short description of this throwable.

From class java.lang.Object

Object	clone() Creates and returns a copy of this Object.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of Class that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object.

Public Constructors

public TooManyListenersException ()

Constructs a TooManyListenersException with no detail message. A detail message is a String that describes this particular exception.

public TooManyListenersException (String s)

Constructs a TooManyListenersException with the specified detail message. A detail message is a String that describes this particular exception.

Parameters

s	the detail message