DataTransferObjectHelper.java

import static java.util.Objects.*;

    public static String[] getNullProperties(Object source) {
        final BeanWrapper wrappedSource = new BeanWrapperImpl(source);
        return Stream.of(wrappedSource.getPropertyDescriptors()).map(FeatureDescriptor::getName)
                .filter(propertyName -> isNull(wrappedSource.getPropertyValue(propertyName))).toArray(String[]::new);
    }

    //copy propreties that ignore null field in the request
    BeanUtils.copyProperties(request, object, getNullProperties(request));