Class CachingBlobStore

    • Method Detail

      • hasVersioning

        public boolean hasVersioning()
        Description copied from interface: BlobStore
        Whether this blob store has versioning.

        With versioning, two writes may use the same key. The returned keys will include a different version number to distinguish the writes.

        Specified by:
        hasVersioning in interface BlobStore
        Overrides:
        hasVersioning in class AbstractBlobStore
      • writeBlob

        public String writeBlob​(BlobWriteContext blobWriteContext)
                         throws IOException
        Description copied from interface: BlobStore
        Writes a blob.

        Note that the returned key may be different than the one requested by the BlobWriteContext, if the blob store needs additional version info to retrieve it.

        Parameters:
        blobWriteContext - the context of the blob write, including the blob
        Returns:
        the key to use to read this blob in the future
        Throws:
        IOException
      • copyBlob

        public boolean copyBlob​(String key,
                                BlobStore sourceStore,
                                String sourceKey,
                                boolean atomicMove)
                         throws IOException
        Description copied from interface: BlobStore
        Writes a file based on a key, as a copy/move from a source in another blob store.

        If the copy/move is requested to be atomic, then the destination file is created atomically. In case of atomic move, in some stores the destination will be created atomically but the source will only be deleted afterwards.

        Parameters:
        key - the key
        sourceStore - the source store
        sourceKey - the source key
        atomicMove - true for an atomic move, false for a regular copy
        Returns:
        true if the file was found in the source store, false if it was not found
        Throws:
        IOException
      • getFile

        public BlobStore.OptionalOrUnknown<PathgetFile​(String key)
        Description copied from interface: BlobStore
        Gets an already-existing file containing the blob for the given key, if present.

        Note that this method is best-effort, it may return unknown even though the blob exists in the store, it's just that it's not handily available locally in a file.

        Parameters:
        key - the blob key
        Returns:
        the file containing the blob, or empty if the blob cannot be found, or unknown if no file is available locally
      • getStream

        public BlobStore.OptionalOrUnknown<InputStreamgetStream​(String key)
                                                           throws IOException
        Description copied from interface: BlobStore
        Gets the stream of the blob for the given key, if present.

        Note that this method is best-effort, it may return unknown even though the blob exists in the store, it's just that it's not efficient to return it as a stream.

        Parameters:
        key - the blob key
        Returns:
        the blob stream, or empty if the blob cannot be found, or unknown if no stream is efficiently available
        Throws:
        IOException
      • readBlob

        public boolean readBlob​(String key,
                                Path dest)
                         throws IOException
        Description copied from interface: BlobStore
        Reads a blob based on its key into the given file.
        Parameters:
        key - the blob key
        dest - the file to use to store the fetched data
        Returns:
        true if the file was fetched, false if the file was not found
        Throws:
        IOException
      • deleteBlob

        public void deleteBlob​(String key)
        Description copied from interface: BlobStore
        Deletes a blob based on a key. No error occurs if the blob does not exist.

        This method does not throw IOException, but may log an error message.

        Parameters:
        key - the blob key