public class CachingMetadataIndex extends CacheOnceMetadataIndex
Constructor and Description |
---|
CachingMetadataIndex(AbstractScaleOutFederation<?> fed,
String name,
long timestamp,
MetadataIndex.MetadataIndexMetadata mdmd)
Cache the index partition metadata in the client.
|
Modifier and Type | Method and Description |
---|---|
PartitionLocator |
find(byte[] key)
Find and return the partition spanning the given key.
|
PartitionLocator |
get(byte[] key)
The partition with that separator key or
null (exact match
on the separator key). |
long |
rangeCount()
Return the #of tuples in the index.
|
long |
rangeCount(byte[] fromKey,
byte[] toKey)
Return the #of tuples in a half-open key range.
|
long |
rangeCountExact(byte[] fromKey,
byte[] toKey)
Return the exact #of tuples in a half-open key range.
|
ITupleIterator |
rangeIterator()
Visits all tuples in key order.
|
ITupleIterator |
rangeIterator(byte[] fromKey,
byte[] toKey)
Return an iterator that visits the entries in a half-open key range.
|
ITupleIterator |
rangeIterator(byte[] fromKey,
byte[] toKey,
int capacity,
int flags,
IFilter filter)
FIXME this is wrong.
|
void |
staleLocator(PartitionLocator locator)
Re-fetches the locator(s).
|
cacheLocators, getIndexMetadata, getScaleOutIndexMetadata, rangeCountExactWithDeleted, toString
public CachingMetadataIndex(AbstractScaleOutFederation<?> fed, String name, long timestamp, MetadataIndex.MetadataIndexMetadata mdmd)
name
- The name of the scale-out index.public void staleLocator(PartitionLocator locator)
staleLocator
in interface IMetadataIndex
staleLocator
in class CacheOnceMetadataIndex
locator
- The locator.public PartitionLocator get(byte[] key)
IMetadataIndex
null
(exact match
on the separator key).get
in interface IMetadataIndex
get
in class CacheOnceMetadataIndex
key
- The separator key (the first key that would go into that
partition).null
.public PartitionLocator find(byte[] key)
IMetadataIndex
find
in interface IMetadataIndex
find
in class CacheOnceMetadataIndex
key
- A key (optional). When null
the locator for the
last index partition will be returned.null
if
there are no partitions defined.public long rangeCount()
IRangeQuery
Note: If the index supports deletion markers then the range count will be an upper bound and may double count tuples which have been overwritten, including the special case where the overwrite is a delete.
rangeCount
in interface IRangeQuery
rangeCount
in class CacheOnceMetadataIndex
ISimpleIndexAccess.rangeCount()
public long rangeCount(byte[] fromKey, byte[] toKey)
IRangeQuery
Note: If the index supports deletion markers then the range count will be an upper bound and may double count tuples which have been overwritten, including the special case where the overwrite is a delete.
rangeCount
in interface IRangeQuery
rangeCount
in class CacheOnceMetadataIndex
fromKey
- The lowest key that will be counted (inclusive). When
null
there is no lower bound.toKey
- The first key that will not be counted (exclusive). When
null
there is no upper bound.public long rangeCountExact(byte[] fromKey, byte[] toKey)
IRangeQuery
Note: If the index supports deletion markers then this operation will require a key-range scan.
rangeCountExact
in interface IRangeQuery
rangeCountExact
in class CacheOnceMetadataIndex
fromKey
- The lowest key that will be counted (inclusive). When
null
there is no lower bound.toKey
- The first key that will not be counted (exclusive). When
null
there is no upper bound.public ITupleIterator rangeIterator()
IRangeQuery
rangeIterator(null, null)
rangeIterator
in interface IRangeQuery
rangeIterator
in class CacheOnceMetadataIndex
public ITupleIterator rangeIterator(byte[] fromKey, byte[] toKey)
IRangeQuery
rangeIterator
in interface IRangeQuery
rangeIterator
in class CacheOnceMetadataIndex
fromKey
- The first key that will be visited (inclusive lower bound).
When null
there is no lower bound.toKey
- The first key that will NOT be visited (exclusive upper
bound). When null
there is no upper bound.SuccessorUtil, which may be used to compute the successor of a value
before encoding it as a component of a key.
,
BytesUtil#successor(byte[]), which may be used to compute the
successor of an encoded key.
,
EntryFilter, which may be used to filter the entries visited by the
iterator.
public ITupleIterator rangeIterator(byte[] fromKey, byte[] toKey, int capacity, int flags, IFilter filter)
delegate
must be a
UnisolatedReadWriteIndex
in order to provide correct locking for
the iterator. The class may have to be refactored in order to permit the
behavior to be gated by an UnisolatedReadWriteIndex
.rangeIterator
in interface IRangeQuery
rangeIterator
in class CacheOnceMetadataIndex
fromKey
- The first key that will be visited (inclusive lower bound).
When null
there is no lower bound.toKey
- The first key that will NOT be visited (exclusive upper
bound). When null
there is no upper bound.capacity
- The #of entries to buffer at a time. This is a hint and MAY be
zero (0) to use an implementation specific default
capacity. A non-zero value may be used if you know that you
want at most N results or if you want to override the default
#of results to be buffered before sending them across a
network interface. (Note that you can control the default
value using
IBigdataClient.Options#DEFAULT_CLIENT_RANGE_QUERY_CAPACITY
).flags
- A bitwise OR of IRangeQuery.KEYS
, IRangeQuery.VALS
, etc.filter
- An optional object used to construct a stacked iterator. When
IRangeQuery.CURSOR
is specified in flags, the base
iterator will implement ITupleCursor
and the first
filter in the stack can safely cast the source iterator to an
ITupleCursor
. If the outermost filter in the stack
does not implement ITupleIterator
, then it will be
wrapped an ITupleIterator
.SuccessorUtil, which may be used to compute the successor of a value
before encoding it as a component of a key.
,
BytesUtil#successor(byte[]), which may be used to compute the
successor of an encoded key.
,
IFilterConstructor, which may be used to construct an iterator stack
performing filtering or other operations.
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