public static class RFile.Reader extends HeapIterator implements FileSKVIterator
Constructor and Description |
---|
RFile.Reader(BlockFileReader rdr) |
Modifier and Type | Method and Description |
---|---|
void |
close() |
void |
closeDeepCopies() |
SortedKeyValueIterator<Key,Value> |
deepCopy(IteratorEnvironment env)
Creates a deep copy of this iterator as though seek had not yet been called.
|
Key |
getFirstKey() |
FileSKVIterator |
getIndex() |
Key |
getLastKey() |
Map<String,ArrayList<ByteSequence>> |
getLocalityGroupCF() |
DataInputStream |
getMetaStore(String name) |
FileSKVIterator |
getSample(SamplerConfigurationImpl sampleConfig) |
void |
init(SortedKeyValueIterator<Key,Value> source,
Map<String,String> options,
IteratorEnvironment env)
Initializes the iterator.
|
void |
printInfo() |
void |
registerMetrics(MetricsGatherer<?> vmg)
Method that registers the given MetricsGatherer.
|
void |
seek(Range range,
Collection<ByteSequence> columnFamilies,
boolean inclusive)
Seeks to the first key in the Range, restricting the resulting K,V pairs to those with the specified columns.
|
void |
setInterruptFlag(AtomicBoolean flag) |
addSource, clear, createHeap, getTopKey, getTopValue, hasTop, next
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
getTopKey, getTopValue, hasTop, next
public RFile.Reader(BlockFileReader rdr) throws IOException
IOException
public void closeDeepCopies()
closeDeepCopies
in interface FileSKVIterator
public void close() throws IOException
close
in interface AutoCloseable
close
in interface FileSKVIterator
IOException
public Key getFirstKey() throws IOException
getFirstKey
in interface FileSKVIterator
IOException
public Key getLastKey() throws IOException
getLastKey
in interface FileSKVIterator
IOException
public DataInputStream getMetaStore(String name) throws IOException, NoSuchMetaStoreException
getMetaStore
in interface FileSKVIterator
IOException
NoSuchMetaStoreException
public SortedKeyValueIterator<Key,Value> deepCopy(IteratorEnvironment env)
SortedKeyValueIterator
deepCopy
in interface SortedKeyValueIterator<Key,Value>
env
- IteratorEnvironment environment in which iterator is being run.public void init(SortedKeyValueIterator<Key,Value> source, Map<String,String> options, IteratorEnvironment env) throws IOException
SortedKeyValueIterator
init
in interface SortedKeyValueIterator<Key,Value>
source
- SortedKeyValueIterator source to read data from.options
- Map map of string option names to option values.env
- IteratorEnvironment environment in which iterator is being run.IOException
- unused.public Map<String,ArrayList<ByteSequence>> getLocalityGroupCF()
public void registerMetrics(MetricsGatherer<?> vmg)
vmg
- MetricsGatherer to be registered with the LocalityGroupReaderspublic void seek(Range range, Collection<ByteSequence> columnFamilies, boolean inclusive) throws IOException
SortedKeyValueIterator
SortedKeyValueIterator.init(org.apache.accumulo.core.iterators.SortedKeyValueIterator<K, V>, java.util.Map<java.lang.String, java.lang.String>, org.apache.accumulo.core.iterators.IteratorEnvironment)
is called.
Iterators that examine groups of adjacent key/value pairs (e.g. rows) to determine their top key and value should be sure that they properly handle a seek
to a key in the middle of such a group (e.g. the middle of a row). Even if the client always seeks to a range containing an entire group (a,c), the tablet
server could send back a batch of entries corresponding to (a,b], then reseek the iterator to range (b,c) when the scan is continued.
columnFamilies
is used, at the lowest level, to determine which data blocks inside of an RFile need to be opened for this iterator. This set of
data blocks is also the set of locality groups defined for the given table. If no columnFamilies are provided, the data blocks for all locality groups
inside of the correct RFile will be opened and seeked in an attempt to find the correct start key, regardless of the startKey in the range
.
In an Accumulo instance in which multiple locality groups exist for a table, it is important to ensure that columnFamilies
is properly set to the
minimum required column families to ensure that data from separate locality groups is not inadvertently read.seek
in interface SortedKeyValueIterator<Key,Value>
range
- Range of keys to iterate over.columnFamilies
- Collection of column families to include or exclude.inclusive
- boolean that indicates whether to include (true) or exclude (false) column families.IOException
- if an I/O error occurs.public FileSKVIterator getIndex() throws IOException
IOException
public FileSKVIterator getSample(SamplerConfigurationImpl sampleConfig)
getSample
in interface FileSKVIterator
public void printInfo() throws IOException
IOException
public void setInterruptFlag(AtomicBoolean flag)
setInterruptFlag
in interface InterruptibleIterator
Copyright © 2011–2016 The Apache Software Foundation. All rights reserved.