public class SnapshotRocksDBKVStore extends RocksDBKVStore implements CloseableKVStore
KVStore view of a RocksDB Snapshot.
Instances must be close()'d when no longer needed to avoid leaking resources associated with iterators.
This class ensures that the configured Snapshot is closed when this instance is closed.
All mutation operations throw UnsupportedOperationException.
| Constructor and Description |
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SnapshotRocksDBKVStore(org.rocksdb.RocksDB db)
Constructor.
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| Modifier and Type | Method and Description |
|---|---|
void |
adjustCounter(byte[] key,
long amount)
Adjust the counter at the given key by the given amount.
|
void |
close()
Close this instance.
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void |
put(byte[] key,
byte[] value)
Set the value associated with the given key.
|
void |
remove(byte[] key)
Remove the key/value pair with the given key, if it exists.
|
void |
removeRange(byte[] minKey,
byte[] maxKey)
Remove all key/value pairs whose keys are in a given range.
|
decodeCounter, encodeCounter, finalize, get, getDB, getRange, toStringgetAtLeast, getAtMostclone, equals, getClass, hashCode, notify, notifyAll, wait, wait, waitapply, decodeCounter, encodeCounter, get, getAtLeast, getAtMost, getRange, getRange, getRange, removeRangepublic SnapshotRocksDBKVStore(org.rocksdb.RocksDB db)
db - RocksDB database to snapshotNullPointerException - if db is nullpublic void close()
RocksDBKVStore
This closes any unclosed iterators returned from getRange().
This does not close the underlying RocksDB or any associated WriteBatch.
close in interface CloseableKVStoreclose in interface Closeableclose in interface AutoCloseableclose in class RocksDBKVStorepublic void put(byte[] key,
byte[] value)
KVStoreput in interface KVStoreput in class RocksDBKVStorekey - keyvalue - valuepublic void remove(byte[] key)
KVStoreremove in interface KVStoreremove in class RocksDBKVStorekey - keypublic void removeRange(byte[] minKey,
byte[] maxKey)
KVStore
The minKey must be less than or equal to maxKey; if they equal (and not null)
then nothing happens; if they are both null then all entries are deleted.
If keys starting with 0xff are not supported by this instance, then:
minKey starts with 0xff, then no change occursmaxKey starts with 0xff, then this method behaves as if maxKey were nullremoveRange in interface KVStoreremoveRange in class AbstractKVStoreminKey - minimum key (inclusive), or null for no minimummaxKey - maximum key (exclusive), or null for no maximumpublic void adjustCounter(byte[] key,
long amount)
KVStoreIdeally this operation should behave in a lock-free manner, so that concurrent transactions can invoke it without conflict. However, when lock-free behavior occurs (if at all) depends on the implementation.
If there is no value associated with key, or key's value is not a valid counter encoding as
would be acceptable to decodeCounter(), then how this operation affects key's
value is undefined.
adjustCounter in interface KVStoreadjustCounter in class RocksDBKVStorekey - keyamount - amount to adjust counter value byCopyright © 2020. All rights reserved.