### Question:
MapperFieldCopy extends Mapper<LogFeederProps> { @Override public boolean init(String inputDesc, String fieldName, String mapClassCode, MapFieldDescriptor mapFieldDescriptor) { init(inputDesc, fieldName, mapClassCode); copyName = ((MapFieldCopyDescriptor)mapFieldDescriptor).getCopyName(); if (StringUtils.isEmpty(copyName)) { LOG.fatal("Map copy name is empty."); return false; } return true; }  @Override boolean init(String inputDesc, String fieldName, String mapClassCode, MapFieldDescriptor mapFieldDescriptor); @Override Object apply(Map<String, Object> jsonObj, Object value);  }### Answer:
@Test public void testMapperFieldCopy_noNewFieldName() { LOG.info("testMapperFieldCopy_noNewFieldName()"); MapFieldCopyDescriptorImpl mapFieldCopyDescriptor = new MapFieldCopyDescriptorImpl(); MapperFieldCopy mapperFieldCopy = new MapperFieldCopy(); assertFalse("Was not able to initialize!", mapperFieldCopy.init(null, "someField", null, mapFieldCopyDescriptor)); }