public class SimpleMetadataStore extends Object implements ConcurrentMetadataStore
MetadataStore that uses a ConcurrentMap for the data store.
The metadata may not be persisted across application restarts, if the provided ConcurrentMap
is an in-memory instance.| Constructor and Description |
|---|
SimpleMetadataStore()
Instantiate a
SimpleMetadataStore using an in-memory ConcurrentHashMap. |
SimpleMetadataStore(ConcurrentMap<String,String> metadata)
Instantiate a
SimpleMetadataStore using the provided ConcurrentMap. |
| Modifier and Type | Method and Description |
|---|---|
String |
get(String key)
Reads a value for the given key from this MetadataStore.
|
void |
put(String key,
String value)
Writes a key value pair to this MetadataStore.
|
String |
putIfAbsent(String key,
String value)
Atomically insert the key into the store.
|
String |
remove(String key)
Remove a value for the given key from this MetadataStore.
|
boolean |
replace(String key,
String oldValue,
String newValue)
Atomically replace the value for the key in the store if the old
value matches the oldValue argument.
|
public SimpleMetadataStore()
SimpleMetadataStore using an in-memory ConcurrentHashMap.public SimpleMetadataStore(ConcurrentMap<String,String> metadata)
SimpleMetadataStore using the provided ConcurrentMap.
The implementation may be a distributed map provided by projects such as Redis and Hazelcast.metadata - the ConcurrentMap instance for metadata.public void put(String key, String value)
MetadataStoreput in interface MetadataStorekey - The key.value - The value.public String get(String key)
MetadataStoreget in interface MetadataStorekey - The key.public String remove(String key)
MetadataStoreremove in interface MetadataStorekey - The key.public String putIfAbsent(String key, String value)
ConcurrentMetadataStoreputIfAbsent in interface ConcurrentMetadataStorekey - The key.value - The value.public boolean replace(String key, String oldValue, String newValue)
ConcurrentMetadataStorereplace in interface ConcurrentMetadataStorekey - The key.oldValue - The old value.newValue - The new value.