Thrown by a method of a
Proxy object if the invoke( )
method of the proxy's
InvocationHandler throws a checked exception not
declared by the original method. This class serves as an unchecked
exception wrapper around the checked exception. Use
getUndeclaredThrowable( ) to obtain the checked
exception thrown by invoke( ). In Java 1.4 and
later, all exceptions can be
"chained" in this way, and
getUndeclaredThrowable( ) is superseded by the
more general getCause( ) method.

public class UndeclaredThrowableException extends RuntimeException {
// Public Constructors
public UndeclaredThrowableException(Throwable undeclaredThrowable);
public UndeclaredThrowableException(Throwable undeclaredThrowable, String s);
// Public Instance Methods
public Throwable getUndeclaredThrowable( );
// Public Methods Overriding Throwable
1.4 public Throwable getCause( );
}