org.opennms.core.spring

Interface FileReloadCallback<T>

Type Parameters:

T - the class of the inner object that is stored in the FileReloadContainer

All Known Implementing Classes:

AbstractJaxbConfigDao.JaxbReloadCallback

public interface FileReloadCallback<T>

Supporting interface for FileReloadContainer for performing a reload callback.

Author:

dj@opennms.org

Method Summary

Modifier and Type	Method and Description
T	reload(T object, org.springframework.core.io.Resource resource) Reload the specified object from the underlying file and return the new object.

Method Detail

reload

T reload(T object,
         org.springframework.core.io.Resource resource)
  throws IOException

Reload the specified object from the underlying file and return the new object. This is called when FileReloadContainer.getObject() determines that the underlying file object has changed.

Any unchecked exceptions that are thrown will be caught by the container, logged, and rethrown with additional details including the object and the file underlying the object. Note that such unchecked exceptions will propogate back up to the caller of getObject(). Unchecked exceptions should be caught if this is not desired. Null can be returned to indicated to the caller that the old object should continue to be used.

Parameters:

object - object to be reloaded. This is useful if the class receiving the callback handles many objects of the same type and needs to know any details about the object being reloaded.

resource - resource for the underlying object that should be used for reloading

Returns:

the new object, or null if the old object should continue being used

Throws:

IOException