### Question:
MultipleInstanceActivityPropertyReader extends ActivityPropertyReader { public String getDataOutput() { return getMultiInstanceLoopCharacteristics() .map(MultiInstanceLoopCharacteristics::getOutputDataItem) .map(MultipleInstanceActivityPropertyReader::createOutputVariable) .orElse(""); } MultipleInstanceActivityPropertyReader(Activity activity, BPMNDiagram diagram, DefinitionResolver definitionResolver); boolean isMultipleInstance(); String getCollectionInput(); String getCollectionOutput(); String getDataInput(); String getDataOutput(); String getCompletionCondition(); boolean isSequential();  }### Answer:
@Test public void testGetEmptyDataOutput() { DataOutput item = mockDataOutput(ITEM_ID, null); when(miloop.getOutputDataItem()).thenReturn(item); assertEquals(ITEM_ID + DELIMITER + DATA_TYPE, reader.getDataOutput()); }
@Test public void testGetDataOutput() { DataOutput item = mockDataOutput(ITEM_ID, PROPERTY_ID); when(miloop.getOutputDataItem()).thenReturn(item); assertEquals(PROPERTY_ID + DELIMITER + DATA_TYPE, reader.getDataOutput()); }