How to ignore null values using springframework BeanUtils copyProperties?

Question

I would like to know how to copy the properties from an Object Source to an Object Dest ignoring null values​​ using Spring Framework.

I actually use Apache beanutils, with this code

    beanUtils.setExcludeNulls(true);     beanUtils.copyProperties(dest, source); 

to do it. But now i need to use Spring.

Any help?

Thx a lot

Answer 1

You can create your own method to copy properties while ignoring null values.

public static String[] getNullPropertyNames (Object source) {     final BeanWrapper src = new BeanWrapperImpl(source);     java.beans.PropertyDescriptor[] pds = src.getPropertyDescriptors();      Set<String> emptyNames = new HashSet<String>();     for(java.beans.PropertyDescriptor pd : pds) {         Object srcValue = src.getPropertyValue(pd.getName());         if (srcValue == null) emptyNames.add(pd.getName());     }      String[] result = new String[emptyNames.size()];     return emptyNames.toArray(result); }  // then use Spring BeanUtils to copy and ignore null using our function public static void myCopyProperties(Object src, Object target) {     BeanUtils.copyProperties(src, target, getNullPropertyNames(src)); } 

Answer 2

Java 8 version of getNullPropertyNames method from alfredx's post:

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