@Override
    protected void process(ComplexEventChunk<StreamEvent> streamEventChunk) {
        synchronized (patternSyncObject) {
            super.process(streamEventChunk);
        }
    }
Implementation of {StreamJunction.Receiver} to receive events to be fed into
single stream stateless queries(Filter).
modules/siddhi-core/src/main/java/io/siddhi/core/query/input/SingleProcessStreamReceiver.java