Java工具类
BeanUtils.copyProperties排除null属性的copy
import com.hourumiyue.system.SpringUtil; import org.springframework.beans.BeanUtils; import org.springframework.beans.BeanWrapper; import org.springframework.beans.BeanWrapperImpl; import org.springframework.beans.BeansException; import org.springframework.context.ApplicationContext; import org.springframework.context.ApplicationContextAware; import java.util.HashSet; import java.util.Set; public class TestBeanUtiles { 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); } //封装同名称属性复制,但是空属性不复制过去 public static void copyPropertiesIgnoreNull(Object src, Object target){ BeanUtils.copyProperties(src, target, getNullPropertyNames(src)); } public static void main(String[] args) { NewPerson newPerson = new NewPerson(); newPerson.setName("miyue");//前台用户更新过的数据,例如前台只修改了用户名 //下面我们假设是从数据库加载出来的老数据 OldPerson oldPerson = new OldPerson(); oldPerson.setSex("nv"); oldPerson.setAge(5); //如果我们想把新数据更新到老数据这个对象里面,我们就可以借助BeanUtils.copyProperties()的方法如下: //BeanUtils.copyProperties(newPerson, oldPerson); copyPropertiesIgnoreNull(newPerson, oldPerson); System.out.println(newPerson.toString()); System.out.println(oldPerson.toString()); } }