public void add(E complexEvents) {
        if (first == null) {
            first = complexEvents;
        } else {
            last.setNext(complexEvents);
        }
        last = getLastEvent(complexEvents);

    }
Collection used to group and manage chunk or ComplexEvents

@param <E> sub types of ComplexEvent such as StreamEvent and StateEvent
modules/siddhi-core/src/main/java/io/siddhi/core/event/ComplexEventChunk.java