/** This function may return cached copies of GoogleCloudStorageItemInfo. */
@Override
public GoogleCloudStorageItemInfo getItemInfo(StorageResourceId resourceId) throws IOException {
// Get the item from cache.
GoogleCloudStorageItemInfo item = cache.getItem(resourceId);
// If it wasn't in the cache, request it then add it.
if (item == null) {
item = super.getItemInfo(resourceId);
cache.putItem(item);
}
return item;
}
@Override
public void close() {
super.close();
// Respect close and empty the cache.
cache.invalidateAll();
}
@Override
public void deleteObjects(List<StorageResourceId> fullObjectNames) throws IOException {
super.deleteObjects(fullObjectNames);
// Remove the deleted objects from cache.
for (StorageResourceId id : fullObjectNames) {
cache.removeItem(id);
}
}
@Override
public void deleteBuckets(List<String> bucketNames) throws IOException {
super.deleteBuckets(bucketNames);
// Remove objects that reside in deleted buckets.
for (String bucket : bucketNames) {
cache.invalidateBucket(bucket);
}
}
@Override
public GoogleCloudStorageItemInfo composeObjects(
List<StorageResourceId> sources, StorageResourceId destination, CreateObjectOptions options)
throws IOException {
GoogleCloudStorageItemInfo item = super.composeObjects(sources, destination, options);
// Cache the composed object.
cache.putItem(item);
return item;
}
@Override
public List<GoogleCloudStorageItemInfo> listBucketInfo() throws IOException {
List<GoogleCloudStorageItemInfo> result = super.listBucketInfo();
// Add the results to the cache.
for (GoogleCloudStorageItemInfo item : result) {
cache.putItem(item);
}
return result;
}
@Override
public List<GoogleCloudStorageItemInfo> updateItems(List<UpdatableItemInfo> itemInfoList)
throws IOException {
List<GoogleCloudStorageItemInfo> result = super.updateItems(itemInfoList);
// Update the cache with the returned items. This overwrites the originals as the
// StorageResourceIds of the items do not change in an update.
for (GoogleCloudStorageItemInfo item : result) {
cache.putItem(item);
}
return result;
}
/** This function may return cached copies of GoogleCloudStorageItemInfo. */
@Override
public List<GoogleCloudStorageItemInfo> getItemInfos(List<StorageResourceId> resourceIds)
throws IOException {
List<GoogleCloudStorageItemInfo> result =
new ArrayList<GoogleCloudStorageItemInfo>(resourceIds.size());
List<StorageResourceId> request = new ArrayList<StorageResourceId>(resourceIds.size());
// Populate the result list with items in the cache, and the request list with resources that
// still need to be resolved. Null items are added to the result list to preserve ordering.
for (StorageResourceId resourceId : resourceIds) {
GoogleCloudStorageItemInfo item = cache.getItem(resourceId);
if (item == null) {
request.add(resourceId);
}
result.add(item);
}
// Resolve all the resources which were not cached, cache them, and add them to the result list.
// Null entries in the result list are replaced by the fresh entries from the underlying
// GoogleCloudStorage.
if (!request.isEmpty()) {
List<GoogleCloudStorageItemInfo> response = super.getItemInfos(request);
Iterator<GoogleCloudStorageItemInfo> responseIterator = response.iterator();
// Iterate through the result set, replacing the null entries added previously with entries
// from the response.
for (int i = 0; i < result.size() && responseIterator.hasNext(); i++) {
if (result.get(i) == null) {
GoogleCloudStorageItemInfo item = responseIterator.next();
cache.putItem(item);
result.set(i, item);
}
}
}
return result;
}
/** This function may return cached copies of GoogleCloudStorageItemInfo. */
@Override
public List<GoogleCloudStorageItemInfo> listObjectInfo(
String bucketName, String objectNamePrefix, String delimiter, long maxResults)
throws IOException {
List<GoogleCloudStorageItemInfo> result;
if (listCachingEnabled) {
result = cache.getList(bucketName, objectNamePrefix);
if (result == null) {
result = super.listObjectInfo(bucketName, objectNamePrefix, null);
cache.putList(bucketName, objectNamePrefix, result);
}
if (GoogleCloudStorage.PATH_DELIMITER.equals(delimiter)) {
filter(result, bucketName, objectNamePrefix, delimiter);
}
} else {
result = super.listObjectInfo(bucketName, objectNamePrefix, null);
cache.putList(bucketName, objectNamePrefix, result);
}
return result;
}
