org.apache.accumulo.core.client.impl

Class ScannerOptions

java.lang.Object

org.apache.accumulo.core.client.impl.ScannerOptions

All Implemented Interfaces:

Iterable<Map.Entry<Key,Value>>, ScannerBase

Direct Known Subclasses:

ClientSideIteratorScanner, IsolatedScanner, MockScannerBase, OfflineScanner, ScannerImpl, TabletServerBatchReader

public class ScannerOptions
extends Object
implements ScannerBase

Field Summary

Fields

Modifier and Type	Field and Description
protected SortedSet<Column>	fetchedColumns
protected List<IterInfo>	serverSideIteratorList
protected Map<String,Map<String,String>>	serverSideIteratorOptions
protected long	timeOut

Constructor Summary

Constructors

Modifier	Constructor and Description
protected	ScannerOptions()
	ScannerOptions(ScannerOptions so)

Method Summary

Methods

Modifier and Type	Method and Description
void	addScanIterator(IteratorSetting si) Add a server-side scan iterator.
void	clearColumns() Clears the columns to be fetched (useful for resetting the scanner for reuse).
void	clearScanIterators() Clears scan iterators prior to returning a scanner to the pool.
void	close() Closes any underlying connections on the scanner
void	fetchColumn(IteratorSetting.Column column) Adds a column to the list of columns that will be fetch by this scanner.
void	fetchColumn(org.apache.hadoop.io.Text colFam, org.apache.hadoop.io.Text colQual) Adds a column to the list of columns that will be fetched by this scanner.
void	fetchColumnFamily(org.apache.hadoop.io.Text col) Adds a column family to the list of columns that will be fetched by this scanner.
Authorizations	getAuthorizations() Returns the authorizations that have been set on the scanner
SortedSet<Column>	getFetchedColumns()
long	getTimeout(TimeUnit timeunit) Returns the setting for how long a scanner will automatically retry when a failure occurs.
Iterator<Map.Entry<Key,Value>>	iterator() Returns an iterator over an accumulo table.
void	removeScanIterator(String iteratorName) Remove an iterator from the list of iterators.
protected static void	setOptions(ScannerOptions dst, ScannerOptions src)
void	setTimeout(long timeout, TimeUnit timeUnit) This setting determines how long a scanner will automatically retry when a failure occurs.
void	updateScanIteratorOption(String iteratorName, String key, String value) Update the options for an iterator.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

serverSideIteratorList

protected List<IterInfo> serverSideIteratorList

serverSideIteratorOptions

protected Map<String,Map<String,String>> serverSideIteratorOptions

fetchedColumns

protected SortedSet<Column> fetchedColumns

timeOut

protected long timeOut

Constructor Detail

ScannerOptions

protected ScannerOptions()

ScannerOptions

public ScannerOptions(ScannerOptions so)

Method Detail

addScanIterator

public void addScanIterator(IteratorSetting si)

Description copied from interface: ScannerBase

Add a server-side scan iterator.

Specified by:

addScanIterator in interface ScannerBase

Parameters:

si - fully specified scan-time iterator, including all options for the iterator. Any changes to the iterator setting after this call are not propagated to the stored iterator.

removeScanIterator

public void removeScanIterator(String iteratorName)

Description copied from interface: ScannerBase

Remove an iterator from the list of iterators.

Specified by:

removeScanIterator in interface ScannerBase

Parameters:

iteratorName - nickname used for the iterator

updateScanIteratorOption

public void updateScanIteratorOption(String iteratorName,
                            String key,
                            String value)

Description copied from interface: ScannerBase

Update the options for an iterator. Note that this does not change the iterator options during a scan, it just replaces the given option on a configured iterator before a scan is started.

Specified by:

updateScanIteratorOption in interface ScannerBase

Parameters:

iteratorName - the name of the iterator to change

key - the name of the option

value - the new value for the named option

fetchColumnFamily

public void fetchColumnFamily(org.apache.hadoop.io.Text col)

Description copied from interface: ScannerBase

Adds a column family to the list of columns that will be fetched by this scanner. By default when no columns have been added the scanner fetches all columns. To fetch multiple column families call this function multiple times.

This can help limit which locality groups are read on the server side.

Specified by:

fetchColumnFamily in interface ScannerBase

Parameters:

col - the column family to be fetched

fetchColumn

public void fetchColumn(org.apache.hadoop.io.Text colFam,
               org.apache.hadoop.io.Text colQual)

Description copied from interface: ScannerBase

Adds a column to the list of columns that will be fetched by this scanner. The column is identified by family and qualifier. By default when no columns have been added the scanner fetches all columns.

Specified by:

fetchColumn in interface ScannerBase

Parameters:

colFam - the column family of the column to be fetched

colQual - the column qualifier of the column to be fetched

fetchColumn

public void fetchColumn(IteratorSetting.Column column)

Description copied from interface: ScannerBase

Adds a column to the list of columns that will be fetch by this scanner.

Specified by:

fetchColumn in interface ScannerBase

Parameters:

column - the IteratorSetting.Column to fetch

clearColumns

public void clearColumns()

Description copied from interface: ScannerBase

Clears the columns to be fetched (useful for resetting the scanner for reuse). Once cleared, the scanner will fetch all columns.

Specified by:

clearColumns in interface ScannerBase

getFetchedColumns

public SortedSet<Column> getFetchedColumns()

clearScanIterators

public void clearScanIterators()

Description copied from interface: ScannerBase

Clears scan iterators prior to returning a scanner to the pool.

Specified by:

clearScanIterators in interface ScannerBase

setOptions

protected static void setOptions(ScannerOptions dst,
              ScannerOptions src)

iterator

public Iterator<Map.Entry<Key,Value>> iterator()

Description copied from interface: ScannerBase

Returns an iterator over an accumulo table. This iterator uses the options that are currently set for its lifetime, so setting options will have no effect on existing iterators.

Keys returned by the iterator are not guaranteed to be in sorted order.

Specified by:

iterator in interface Iterable<Map.Entry<Key,Value>>

Specified by:

iterator in interface ScannerBase

Returns:

an iterator over Key,Value pairs which meet the restrictions set on the scanner

setTimeout

public void setTimeout(long timeout,
              TimeUnit timeUnit)

Description copied from interface: ScannerBase

This setting determines how long a scanner will automatically retry when a failure occurs. By default, a scanner will retry forever.

Setting the timeout to zero (with any time unit) or Long.MAX_VALUE (with TimeUnit.MILLISECONDS) means no timeout.

Specified by:

setTimeout in interface ScannerBase

Parameters:

timeout - the length of the timeout

timeUnit - the units of the timeout

getTimeout

public long getTimeout(TimeUnit timeunit)

Description copied from interface: ScannerBase

Returns the setting for how long a scanner will automatically retry when a failure occurs.

Specified by:

getTimeout in interface ScannerBase

Returns:

the timeout configured for this scanner

close

public void close()

Description copied from interface: ScannerBase

Closes any underlying connections on the scanner

Specified by:

close in interface ScannerBase

getAuthorizations

public Authorizations getAuthorizations()

Description copied from interface: ScannerBase

Returns the authorizations that have been set on the scanner

Specified by:

getAuthorizations in interface ScannerBase

Returns:

The authorizations set on the scanner instance