public class ArrayKVStore extends AbstractKVStore
KVStore based on a sorted array of key/value pairs.
Instances query three ByteBuffers, one for the array index, one for the key data, and one for the value data.
Data for these ByteBuffers is created using ArrayKVWriter.
Instances are optimized for minimal memory overhead and queries using keys sharing a prefix with the previously queried key. Key data is prefix-compressed.
Key and value data must not exceed 2GB (each separately).
| Constructor and Description |
|---|
ArrayKVStore(ByteBuffer indx,
ByteBuffer keys,
ByteBuffer vals)
Constructor.
|
| Modifier and Type | Method and Description |
|---|---|
byte[] |
get(byte[] key)
Get the value associated with the given key, if any.
|
KVPair |
getAtLeast(byte[] minKey,
byte[] maxKey)
Get the key/value pair having the smallest key greater than or equal to the given minimum, if any.
|
KVPair |
getAtMost(byte[] maxKey,
byte[] minKey)
Get the key/value pair having the largest key strictly less than the given maximum, if any.
|
CloseableIterator<KVPair> |
getRange(byte[] minKey,
byte[] maxKey,
boolean reverse)
Iterate the key/value pairs in the specified range.
|
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.
|
adjustCounter, decodeCounter, encodeCounterclone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, waitapply, getRange, getRange, removeRangepublic ArrayKVStore(ByteBuffer indx, ByteBuffer keys, ByteBuffer vals)
indx - buffer containing index data written by a ArrayKVWriterkeys - buffer containing key data written by a ArrayKVWritervals - buffer containing value data written by a ArrayKVWriterIllegalArgumentException - if any parameter is nullIllegalArgumentException - if indx size is not a correct multiplepublic byte[] get(byte[] key)
KVStore
Modifications to the returned byte[] array do not affect this instance.
get in interface KVStoreget in class AbstractKVStorekey - keypublic KVPair getAtLeast(byte[] minKey, byte[] maxKey)
KVStore
An optional (exclusive) maximum key may also be specified; if maxKey is null, there is no upper bound;
if maxKey <= minKey, null is always returned.
If keys starting with 0xff are not supported by this instance, and minKey starts with 0xff,
then this method returns null.
Modifications to the returned byte[] arrays do not affect this instance.
getAtLeast in interface KVStoregetAtLeast in class AbstractKVStoreminKey - minimum key (inclusive), or null for no minimum (get the smallest key)maxKey - maximum key (exclusive), or null for no maximum (no upper bound)key >= minKey and key < maxKey, or null if none existspublic KVPair getAtMost(byte[] maxKey, byte[] minKey)
KVStore
An optional (inclusive) minimum key may also be specified; if minKey is null, there is no lower bound
(equivalent to a lower bound of the empty byte array); if minKey >= maxKey, null is always returned.
If keys starting with 0xff are not supported by this instance, and maxKey starts with 0xff,
then this method behaves as if maxKey were null.
Modifications to the returned byte[] arrays do not affect this instance.
getAtMost in interface KVStoregetAtMost in class AbstractKVStoremaxKey - maximum key (exclusive), or null for no maximum (get the largest key)minKey - minimum key (inclusive), or null for no minimum (no lower bound)key < maxKey and key >= minKey, or null if none existspublic CloseableIterator<KVPair> getRange(byte[] minKey, byte[] maxKey, boolean reverse)
KVStoreIterator's
remove() method must be supported and should have the same effect as
invoking remove() on the corresponding key.
If keys starting with 0xff are not supported by this instance, and minKey starts with 0xff,
then this method returns an empty iteration.
If keys starting with 0xff are not supported by this instance, and maxKey starts with 0xff,
then this method behaves as if maxKey were null.
The returned Iterator must not throw ConcurrentModificationException;
however, whether or not a "live" Iterator reflects any modifications made after its creation is
implementation dependent. Implementations that do make post-creation updates visible in the Iterator,
even if the update occurs after some delay, must preserve the order in which the modifications actually occurred.
The returned Iterator itself is not guaranteed to be thread safe.
Invokers of this method are encouraged to close() the returned iterators,
though this is not required for correct behavior.
Modifications to the returned KVPair key and value byte[] arrays do not affect this instance.
minKey - minimum key (inclusive), or null for no minimum (start at the smallest key)maxKey - maximum key (exclusive), or null for no maximum (end at the largest key)reverse - true to return key/value pairs in reverse order (i.e., keys descending)minKey (inclusive) to maxKey (exclusive)public void put(byte[] key,
byte[] value)
KVStoreput in interface KVStoreput in class AbstractKVStorekey - keyvalue - valuepublic void remove(byte[] key)
KVStoreremove in interface KVStoreremove in class AbstractKVStorekey - 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 maximumCopyright © 2022. All rights reserved.