扩展spring的BeanUtils，增加拷贝属性排除null值的功能(注：String为null不考虑)

朱雀 2022-07-14 04:38 209阅读 0赞

public class BeanUtils extends org.springframework.beans.BeanUtils \{  
  
  
public static void copyNotNullProperties(Object source, Object target, String\[\] ignoreProperties) throws BeansException \{  
copyNotNullProperties(source, target, null, ignoreProperties);  
\}  
  
  
public static void copyNotNullProperties(Object source, Object target, Class<?> editable) throws BeansException \{  
copyNotNullProperties(source, target, editable, null);  
\}  
  
  
public static void copyNotNullProperties(Object source, Object target) throws BeansException \{  
copyNotNullProperties(source, target, null, null);  
\}  
  
  
private static void copyNotNullProperties(Object source, Object target, Class<?> editable, String\[\] ignoreProperties) throws BeansException \{  
  
  
Assert.notNull(source, "Source must not be null");  
Assert.notNull(target, "Target must not be null");  
  
  
Class<?> actualEditable = target.getClass();  
if (editable != null) \{  
if (!editable.isInstance(target)) \{  
throw new IllegalArgumentException("Target class \[" + target.getClass().getName() + "\] not assignable to Editable class \[" + editable.getName() + "\]");  
\}  
actualEditable = editable;  
\}  
PropertyDescriptor\[\] targetPds = getPropertyDescriptors(actualEditable);  
List<String> ignoreList = (ignoreProperties != null) ? Arrays.asList(ignoreProperties) : null;  
  
  
for (PropertyDescriptor targetPd : targetPds) \{  
if (targetPd.getWriteMethod() != null && (ignoreProperties == null || (!ignoreList.contains(targetPd.getName())))) \{  
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);  
if (value != null || readMethod.getReturnType().getName().equals("java.lang.String")) \{// 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，如果是String类型，则不需要验证是否为空  
boolean isEmpty = false;  
if (value instanceof Set) \{  
Set s = (Set) value;  
if (s == null || s.isEmpty()) \{  
isEmpty = true;  
\}  
\} else if (value instanceof Map) \{  
Map m = (Map) value;  
if (m == null || m.isEmpty()) \{  
isEmpty = true;  
\}  
\} else if (value instanceof List) \{  
List l = (List) value;  
if (l == null || l.size() < 1) \{  
isEmpty = true;  
\}  
\} else if (value instanceof Collection) \{  
Collection c = (Collection) value;  
if (c == null || c.size() < 1) \{  
isEmpty = true;  
\}  
\}  
if (!isEmpty) \{  
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);  
\}  
\}  
\}  
\}  
\}  
  
  
\}