The error can be reproduced by running the following script (I ran it in the Script Editor):
#@ OpService ops
#@ Img inputData
#@OUTPUT net.imglib2.roi.labeling.ImgLabeling labeling
from net.imglib2.algorithm.labeling.ConnectedComponents import StructuringElement
from net.imglib2.roi.labeling import ImgLabeling;
# otsu threshold and display
thresholded = ops.threshold().otsu(inputData)
# call connected components to label each connected region
labeling = ops.labeling().cca(thresholded, StructuringElement.FOUR_CONNECTED)
The error can be reproduced by running the following script (I ran it in the Script Editor):