1. BeanUtils.copyProperties(Object source, Object target)

用法: 讲source的属性值复制到target，属性为null时也会进行复制。

需求：排除null值进行复制

public class CopyObjectUtil {


    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);
    }

    public static void copyPropertiesIgnoreNull(Object src, Object target) {
        BeanUtils.copyProperties(src, target, getNullPropertyNames(src));
    }


}

使用方式与BeanUtils.copyProperties相同:

CopyObjectUtil.copyPropertiesIgnoreNull(Object source, Object target);

2. BeanUtils.copyProperties(Object source, Object target, new String[] { “id”, “createDate”, “modifyDate” })

用法：排除指定字段进行复制