Package org.opennms.features.distributed.kvstore.blob.noop

Class NoOpBlobStore

  • All Implemented Interfaces:
    BlobStore, KeyValueStore<byte[]>
    public class NoOpBlobStore
extends AbstractAsyncKeyValueStore<byte[]>
implements BlobStore
    A key value store that does nothing. Since no puts result in any operation, all retrieves will always return an empty optional. This implies any clients using this will also be holding onto their own local copies of the key-values since persisting to this won't store them.

    • Constructor Detail

      • NoOpBlobStore

        public NoOpBlobStore()

    • Method Detail

      • getInstance

        public static BlobStore getInstance()

      • put

        public long put​(String key,
                byte[] value,
                String context,
                Integer ttlInSeconds)
        Description copied from interface: KeyValueStore
        Put a value with a suggested time-to-live after which the value should be expired and removed from the store.

        Records are expired on a best effort basis and depending on the implementation it is possible to get an expired record.

        Specified by:
        put in interface KeyValueStore<byte[]>
        context - a context used to differentiate between keys with the same name (forms a compound key)
        ttlInSeconds - the time to live in seconds for this key or no ttl if null
        Returns:
        the timestamp the value was persisted with

      • get

        public Optional<byte[]> get​(String key,
                            String context)
        Specified by:
        get in interface KeyValueStore<byte[]>
        context - a context used to differentiate between keys with the same name (forms a compound key)
        Returns:
        an optional containing the value if present or empty if the key did not exist

      • getIfStale

        public Optional<Optional<byte[]>> getIfStale​(String key,
                                             String context,
                                             long timestamp)
        Specified by:
        getIfStale in interface KeyValueStore<byte[]>
        context - a context used to differentiate between keys with the same name (forms a compound key)
        timestamp - the timestamp of the last known state such that if an record with a more recent timestamp is found the provided timestamp will be considered stale and the new record will be returned
        Returns:
        an optional that will be empty if the key was not found or will contain another optional that will be empty if not stale or contain the value if stale

      • getLastUpdated

        public OptionalLong getLastUpdated​(String key,
                                   String context)
        Specified by:
        getLastUpdated in interface KeyValueStore<byte[]>
        context - a context used to differentiate between keys with the same name (forms a compound key)
        Returns:
        an optional containing the timestamp the key's value was last updated or empty if the key did not exist

      • addListener

        public void addListener​(KeyValueStore<byte[]> listener)

      • getName

        public String getName()
        Specified by:
        getName in interface KeyValueStore<byte[]>
        Returns:
        the name of the backing implementation

      • enumerateContext

        public Map<String,​byte[]> enumerateContext​(String context)
        Specified by:
        enumerateContext in interface KeyValueStore<byte[]>
        Parameters:
        context - a context used to differentiate between keys with the same name (forms a compound key)
        Returns:
        a map of all the records matching the given context where the map's key is the record's key and the map's value is the records value

      • delete

        public void delete​(String key,
                   String context)
        Specified by:
        delete in interface KeyValueStore<byte[]>
        context - a context used to differentiate between keys with the same name (forms a compound key)