【java】对象非空属性复制

public abstract class BeanUtils extends org.springframework.beans.BeanUtils {  
    
	/**
	 * 功能 : 只复制source对象的非空属性到target对象上
	 * */
    public static void copyNoNullProperties(Object source, Object target) throws BeansException {  
      Assert.notNull(source, "Source must not be null");  
      Assert.notNull(target, "Target must not be null");  
      Class<?> actualEditable = target.getClass();  
      PropertyDescriptor[] targetPds = getPropertyDescriptors(actualEditable);  
      for (PropertyDescriptor targetPd : targetPds) {  
        if (targetPd.getWriteMethod() != null) {  
          PropertyDescriptor sourcePd = getPropertyDescriptor(source.getClass(), targetPd.getName());  
          if (sourcePd != null && sourcePd.getReadMethod() != null) {  
            try {  
              Method readMethod = sourcePd.getReadMethod();  
              if (!Modifier.isPublic(readMethod.getDeclaringClass().getModifiers())) {  
                readMethod.setAccessible(true);  
              }  
              Object value = readMethod.invoke(source);  
              // 这里判断以下value是否为空 当然这里也能进行一些特殊要求的处理 例如绑定时格式转换等等  
              if (value != null) {  
                Method writeMethod = targetPd.getWriteMethod();  
                if (!Modifier.isPublic(writeMethod.getDeclaringClass().getModifiers())) {  
                  writeMethod.setAccessible(true);  
                }  
                writeMethod.invoke(target, value);  
              }  
            } catch (Throwable ex) {  
              throw new FatalBeanException("Could not copy properties from source to target", ex);  
            }  
          }  
        }  
      }  
    }  
  }