java-如何检查列表或集合类型的字段是否为空?
我有以下代码:java-如何检查列表或集合类型的字段是否为空?,java,Java,我有以下代码: for (final Field field : fields) { if (Collection.class.isAssignableFrom(field.getType())) { } } 如何检查字段(可以是列表或集合类型)是空的还是空的?您可以使用以下方法: for (final Field field : fields) { if (Collection.class.isAssignableFrom(field.getType()))
for (final Field field : fields) {
if (Collection.class.isAssignableFrom(field.getType())) {
}
}
如何检查字段(可以是列表或集合类型)是空的还是空的?您可以使用以下方法:
for (final Field field : fields)
{
if (Collection.class.isAssignableFrom(field.getType()))
{
field.setAccessible(true); // required if the field is not public (that is very likely)
if (((Collection) field.get(object)).isEmpty()) // "object" being the object which owns your fields
{
System.out.println("Field is empty");
}
}
}
也。