### Question:
ColumnMappingControllerImpl implements MutableColumnMappingController { private ColumnMappingType getColumnMapping(final String definedColumn) { return myColumnMappings.getColumnMapping().stream().filter(cm -> cm.getName().equals(definedColumn)).findAny() .orElse(null); } ColumnMappingControllerImpl(PreferencesRegistry preferencesRegistry); synchronized void initialize(); @Override synchronized boolean supportsTypes(String fromType, Set<String> cols, List<String> toTypes); @Override Map<String, Map<String, String>> getDefinedColumns(List<Pair<String, List<String>>> layers); @Override synchronized Collection<String> getDefinedColumns(); @Override synchronized String getDefinedColumn(String layerKey, String layerColumn); @Override synchronized String getLayerColumn(String layerKey, String definedColumn); @Override synchronized List<ColumnMapping> getMappings(String definedColumn); @Override String getMappedColumn(String sourceColumn, String sourceLayerKey, String targetLayerKey); @Override synchronized String getDescription(String definedColumn); @Override synchronized String getType(String definedColumn); @Override synchronized boolean canAssociate(String type1, String col1, String type2, String col2); @Override synchronized void associate(String t1, String f1, String t2, String f2, String valType); @Override synchronized void addMapping(String definedColumn, String layerKey, String layerColumn, boolean overwrite); @Override synchronized void rename(String definedColumn, String newColumn); @Override synchronized void setDescription(String definedColumn, String description, boolean overwrite); @Override synchronized void setType(String definedColumn, String type, boolean overwrite); @Override synchronized void clearMappings(String definedColumn); @Override synchronized void remove(String definedColumn); @Override void addListener(Consumer<Void> listener); @Override void removeListener(Consumer<Void> listener);  }### Answer:
@Test public void testMarshalling() throws JAXBException { ColumnMappings input = ColumnMappingUtilsTest.newColumnMappings(); ByteArrayOutputStream outputStream = new ByteArrayOutputStream(); XMLUtilities.writeXMLObject(input, outputStream); ColumnMappings result = XMLUtilities.readXMLObject(new ByteArrayInputStream(outputStream.toByteArray()), ColumnMappings.class); Assert.assertEquals(1, result.getColumnMapping().size()); ColumnMappingUtilsTest.assertEquals(input, result); }