question: @ SuppressWarnings ( "unchecked" ) private < T > T lookDependencyAmongDependants ( final Class < T > dependencyType ) { for ( int i = dependants . size ( ) - 1 ; i >= 0 ; i -- ) { final Object dependant = dependants . get ( i ) ; if ( dependencyType . isAssignableFrom ( dependant . getClass ( ) ) ) { dependants . remove ( dependant ) ; return cache ( dependencyType , dependant ) ; } } return null ; }
target:  Checks it the requested dependency is one of the cached dependent instances.