org.apache.hadoop.hbase.client

Class ImmutableScan

java.lang.Object

org.apache.hadoop.hbase.client.Operation

org.apache.hadoop.hbase.client.OperationWithAttributes

org.apache.hadoop.hbase.client.Query

org.apache.hadoop.hbase.client.Scan

org.apache.hadoop.hbase.client.ImmutableScan

All Implemented Interfaces:

Attributes

@InterfaceAudience.Private
public final class ImmutableScan
extends Scan

Immutable version of Scan

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.hbase.client.Scan

Scan.ReadType

Field Summary

Fields inherited from class org.apache.hadoop.hbase.client.Scan

DEFAULT_HBASE_CLIENT_SCANNER_ASYNC_PREFETCH, HBASE_CLIENT_SCANNER_ASYNC_PREFETCH, SCAN_ATTRIBUTES_METRICS_DATA, SCAN_ATTRIBUTES_METRICS_ENABLE, SCAN_ATTRIBUTES_TABLE_NAME

Fields inherited from class org.apache.hadoop.hbase.client.Query

colFamTimeRangeMap, consistency, filter, loadColumnFamiliesOnDemand, targetReplicaId

Fields inherited from class org.apache.hadoop.hbase.client.OperationWithAttributes

ID_ATRIBUTE

Constructor Summary

Constructors

Constructor and Description
ImmutableScan(Scan scan) Create Immutable instance of Scan from given Scan object

Method Summary

Modifier and Type	Method and Description
Scan	addColumn(byte[] family, byte[] qualifier) Get the column from the specified family with the specified qualifier.
Scan	addFamily(byte[] family) Get all columns from the specified family.
boolean	doLoadColumnFamiliesOnDemand() Get the logical value indicating whether on-demand CF loading should be allowed.
byte[]	getACL()
boolean	getAllowPartialResults()
byte[]	getAttribute(String name) Gets an attribute
long	getAttributeSize()
Map<String,byte[]>	getAttributesMap() Gets all attributes
Authorizations	getAuthorizations()
int	getBatch()
boolean	getCacheBlocks() Get whether blocks should be cached for this Scan.
int	getCaching()
Map<byte[],TimeRange>	getColumnFamilyTimeRange()
Consistency	getConsistency() Returns the consistency level for this operation
byte[][]	getFamilies()
Map<byte[],NavigableSet<byte[]>>	getFamilyMap() Getting the familyMap
Filter	getFilter()
Map<String,Object>	getFingerprint() Compile the table and column family (i.e.
String	getId() This method allows you to retrieve the identifier for the operation if one was set.
IsolationLevel	getIsolationLevel()
int	getLimit()
Boolean	getLoadColumnFamiliesOnDemandValue() Get the raw loadColumnFamiliesOnDemand setting; if it's not set, can be null.
long	getMaxResultSize()
int	getMaxResultsPerColumnFamily()
int	getMaxVersions()
int	getPriority()
Scan.ReadType	getReadType()
int	getReplicaId() Returns region replica id where Query will fetch data from.
int	getRowOffsetPerColumnFamily() Method for retrieving the scan's offset per row per column family (#kvs to be skipped)
byte[]	getStartRow()
byte[]	getStopRow()
TimeRange	getTimeRange()
boolean	hasFamilies()
boolean	hasFilter()
boolean	includeStartRow()
boolean	includeStopRow()
Boolean	isAsyncPrefetch()
boolean	isGetScan()
boolean	isNeedCursorResult()
boolean	isRaw()
boolean	isReversed() Get whether this scan is a reversed one.
boolean	isScanMetricsEnabled()
boolean	isSmall() Deprecated.
int	numFamilies()
Scan	readAllVersions() Get all available versions.
Scan	readVersions(int versions) Get up to the specified number of versions of each column.
Scan	setACL(Map<String,Permission> perms)
Scan	setACL(String user, Permission perms)
Scan	setAllowPartialResults(boolean allowPartialResults) Setting whether the caller wants to see the partial results when server returns less-than-expected cells.
Scan	setAsyncPrefetch(boolean asyncPrefetch) Deprecated.
Scan	setAttribute(String name, byte[] value) Sets an attribute.
Scan	setAuthorizations(Authorizations authorizations) Sets the authorizations to be used by this Query
Scan	setBatch(int batch) Set the maximum number of cells to return for each call to next().
Scan	setCacheBlocks(boolean cacheBlocks) Set whether blocks should be cached for this Scan.
Scan	setCaching(int caching) Set the number of rows for caching that will be passed to scanners.
Scan	setColumnFamilyTimeRange(byte[] cf, long minStamp, long maxStamp) Get versions of columns only within the specified timestamp range, [minStamp, maxStamp) on a per CF bases.
Scan	setConsistency(Consistency consistency) Sets the consistency level for this operation
Scan	setFamilyMap(Map<byte[],NavigableSet<byte[]>> familyMap) Setting the familyMap
Scan	setFilter(Filter filter) Apply the specified server-side filter when performing the Query.
Scan	setId(String id) This method allows you to set an identifier on an operation.
Scan	setIsolationLevel(IsolationLevel level) Set the isolation level for this query.
Scan	setLimit(int limit) Set the limit of rows for this scan.
Scan	setLoadColumnFamiliesOnDemand(boolean value) Set the value indicating whether loading CFs on demand should be allowed (cluster default is false).
Scan	setMaxResultSize(long maxResultSize) Set the maximum result size.
Scan	setMaxResultsPerColumnFamily(int limit) Set the maximum number of values to return per row per Column Family
Scan	setNeedCursorResult(boolean needCursorResult) When the server is slow or we scan a table with many deleted data or we use a sparse filter, the server will response heartbeat to prevent timeout.
Scan	setOneRowLimit() Call this when you only want to get one row.
Scan	setPriority(int priority)
Scan	setRaw(boolean raw) Enable/disable "raw" mode for this scan.
Scan	setReadType(Scan.ReadType readType) Set the read type for this scan.
Scan	setReplicaId(int id) Specify region replica id where Query will fetch data from.
Scan	setReversed(boolean reversed) Set whether this scan is a reversed one
Scan	setRowOffsetPerColumnFamily(int offset) Set offset for the row per Column Family.
Scan	setRowPrefixFilter(byte[] rowPrefix) Set a filter (using stopRow and startRow) so the result set only contains rows where the rowKey starts with the specified prefix.
Scan	setScanMetricsEnabled(boolean enabled) Enable collection of ScanMetrics.
Scan	setSmall(boolean small) Deprecated.
Scan	setTimeRange(long minStamp, long maxStamp) Get versions of columns only within the specified timestamp range, [minStamp, maxStamp).
Scan	setTimestamp(long timestamp) Get versions of columns with the specified timestamp.
Scan	setTimeStamp(long timestamp) Deprecated.
String	toJSON() Produces a JSON object sufficient for description of a query in a debugging or logging context.
String	toJSON(int maxCols) Produces a JSON object for fingerprint and details exposure in a parseable format.
Map<String,Object>	toMap() Produces a Map containing a full summary of a query.
Map<String,Object>	toMap(int maxCols) Compile the details beyond the scope of getFingerprint (row, columns, timestamps, etc.) into a Map along with the fingerprinted information.
String	toString() Produces a string representation of this Operation.
String	toString(int maxCols) Produces a string representation of this Operation.
Scan	withStartRow(byte[] startRow) Set the start row of the scan.
Scan	withStartRow(byte[] startRow, boolean inclusive) Set the start row of the scan.
Scan	withStopRow(byte[] stopRow) Set the stop row of the scan.
Scan	withStopRow(byte[] stopRow, boolean inclusive) Set the stop row of the scan.

Methods inherited from class org.apache.hadoop.hbase.client.Scan

createScanFromCursor, getScanMetrics, setMaxVersions, setMaxVersions, setStartRow, setStopRow

Methods inherited from class java.lang.Object

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

Constructor Detail

ImmutableScan

public ImmutableScan(Scan scan)

Create Immutable instance of Scan from given Scan object

Parameters:

scan - Copy all values from Scan

Method Detail

addFamily

public Scan addFamily(byte[] family)

Description copied from class: Scan

Get all columns from the specified family.

Overrides previous calls to addColumn for this family.

Overrides:

addFamily in class Scan

Parameters:

family - family name

Returns:

this

addColumn

public Scan addColumn(byte[] family,
                      byte[] qualifier)

Description copied from class: Scan

Get the column from the specified family with the specified qualifier.

Overrides previous calls to addFamily for this family.

Overrides:

addColumn in class Scan

Parameters:

family - family name

qualifier - column qualifier

Returns:

this

setTimeRange

public Scan setTimeRange(long minStamp,
                         long maxStamp)

Description copied from class: Scan

Get versions of columns only within the specified timestamp range, [minStamp, maxStamp). Note, default maximum versions to return is 1. If your time range spans more than one version and you want all versions returned, up the number of versions beyond the default.

Overrides:

setTimeRange in class Scan

Parameters:

minStamp - minimum timestamp value, inclusive

maxStamp - maximum timestamp value, exclusive

Returns:

this

See Also:

Scan.setMaxVersions(), Scan.setMaxVersions(int)

setTimeStamp

@Deprecated
public Scan setTimeStamp(long timestamp)

Deprecated.

Description copied from class: Scan

Get versions of columns with the specified timestamp. Note, default maximum versions to return is 1. If your time range spans more than one version and you want all versions returned, up the number of versions beyond the defaut.

Overrides:

setTimeStamp in class Scan

Parameters:

timestamp - version timestamp

Returns:

this

See Also:

Scan.setMaxVersions(), Scan.setMaxVersions(int)

setTimestamp

public Scan setTimestamp(long timestamp)

Description copied from class: Scan

Get versions of columns with the specified timestamp. Note, default maximum versions to return is 1. If your time range spans more than one version and you want all versions returned, up the number of versions beyond the defaut.

Overrides:

setTimestamp in class Scan

Parameters:

timestamp - version timestamp

Returns:

this

See Also:

Scan.setMaxVersions(), Scan.setMaxVersions(int)

setColumnFamilyTimeRange

public Scan setColumnFamilyTimeRange(byte[] cf,
                                     long minStamp,
                                     long maxStamp)

Description copied from class: Query

Get versions of columns only within the specified timestamp range, [minStamp, maxStamp) on a per CF bases. Note, default maximum versions to return is 1. If your time range spans more than one version and you want all versions returned, up the number of versions beyond the default. Column Family time ranges take precedence over the global time range.

Overrides:

setColumnFamilyTimeRange in class Scan

Parameters:

cf - the column family for which you want to restrict

minStamp - minimum timestamp value, inclusive

maxStamp - maximum timestamp value, exclusive

Returns:

this

withStartRow

public Scan withStartRow(byte[] startRow)

Description copied from class: Scan

Set the start row of the scan.

If the specified row does not exist, the Scanner will start from the next closest row after the specified row.

Overrides:

withStartRow in class Scan

Parameters:

startRow - row to start scanner at or after

Returns:

this

withStartRow

public Scan withStartRow(byte[] startRow,
                         boolean inclusive)

Description copied from class: Scan

Set the start row of the scan.

If the specified row does not exist, or the inclusive is false, the Scanner will start from the next closest row after the specified row.

Overrides:

withStartRow in class Scan

Parameters:

startRow - row to start scanner at or after

inclusive - whether we should include the start row when scan

Returns:

this

withStopRow

public Scan withStopRow(byte[] stopRow)

Description copied from class: Scan

Set the stop row of the scan.

The scan will include rows that are lexicographically less than the provided stopRow.

Note: When doing a filter for a rowKey Prefix use Scan.setRowPrefixFilter(byte[]). The 'trailing 0' will not yield the desired result.

Overrides:

withStopRow in class Scan

Parameters:

stopRow - row to end at (exclusive)

Returns:

this

withStopRow

public Scan withStopRow(byte[] stopRow,
                        boolean inclusive)

Description copied from class: Scan

Set the stop row of the scan.

The scan will include rows that are lexicographically less than (or equal to if inclusive is true) the provided stopRow.

Overrides:

withStopRow in class Scan

Parameters:

stopRow - row to end at

inclusive - whether we should include the stop row when scan

Returns:

this

setRowPrefixFilter

public Scan setRowPrefixFilter(byte[] rowPrefix)

Description copied from class: Scan

Set a filter (using stopRow and startRow) so the result set only contains rows where the rowKey starts with the specified prefix.

This is a utility method that converts the desired rowPrefix into the appropriate values for the startRow and stopRow to achieve the desired result.

This can safely be used in combination with setFilter.

NOTE: Doing a Scan.setStartRow(byte[]) and/or Scan.setStopRow(byte[]) after this method will yield undefined results.

Overrides:

setRowPrefixFilter in class Scan

Parameters:

rowPrefix - the prefix all rows must start with. (Set null to remove the filter.)

Returns:

this

readAllVersions

public Scan readAllVersions()

Description copied from class: Scan

Get all available versions.

Overrides:

readAllVersions in class Scan

Returns:

this

readVersions

public Scan readVersions(int versions)

Description copied from class: Scan

Get up to the specified number of versions of each column.

Overrides:

readVersions in class Scan

Parameters:

versions - specified number of versions for each column

Returns:

this

setBatch

public Scan setBatch(int batch)

Description copied from class: Scan

Set the maximum number of cells to return for each call to next(). Callers should be aware that this is not equivalent to calling Scan.setAllowPartialResults(boolean). If you don't allow partial results, the number of cells in each Result must equal to your batch setting unless it is the last Result for current row. So this method is helpful in paging queries. If you just want to prevent OOM at client, use setAllowPartialResults(true) is better.

Overrides:

setBatch in class Scan

Parameters:

batch - the maximum number of values

See Also:

Result.mayHaveMoreCellsInRow()

setMaxResultsPerColumnFamily

public Scan setMaxResultsPerColumnFamily(int limit)

Description copied from class: Scan

Set the maximum number of values to return per row per Column Family

Overrides:

setMaxResultsPerColumnFamily in class Scan

Parameters:

limit - the maximum number of values returned / row / CF

setRowOffsetPerColumnFamily

public Scan setRowOffsetPerColumnFamily(int offset)

Description copied from class: Scan

Set offset for the row per Column Family.

Overrides:

setRowOffsetPerColumnFamily in class Scan

Parameters:

offset - is the number of kvs that will be skipped.

setCaching

public Scan setCaching(int caching)

Description copied from class: Scan

Set the number of rows for caching that will be passed to scanners. If not set, the Configuration setting HConstants.HBASE_CLIENT_SCANNER_CACHING will apply. Higher caching values will enable faster scanners but will use more memory.

Overrides:

setCaching in class Scan

Parameters:

caching - the number of rows for caching

setMaxResultSize

public Scan setMaxResultSize(long maxResultSize)

Description copied from class: Scan

Set the maximum result size. The default is -1; this means that no specific maximum result size will be set for this scan, and the global configured value will be used instead. (Defaults to unlimited).

Overrides:

setMaxResultSize in class Scan

Parameters:

maxResultSize - The maximum result size in bytes.

setFilter

public Scan setFilter(Filter filter)

Description copied from class: Query

Apply the specified server-side filter when performing the Query. Only Filter.filterCell(org.apache.hadoop.hbase.Cell) is called AFTER all tests for ttl, column match, deletes and column family's max versions have been run.

Overrides:

setFilter in class Scan

Parameters:

filter - filter to run on the server

Returns:

this for invocation chaining

setFamilyMap

public Scan setFamilyMap(Map<byte[],NavigableSet<byte[]>> familyMap)

Description copied from class: Scan

Setting the familyMap

Overrides:

setFamilyMap in class Scan

Parameters:

familyMap - map of family to qualifier

Returns:

this

setCacheBlocks

public Scan setCacheBlocks(boolean cacheBlocks)

Description copied from class: Scan

Set whether blocks should be cached for this Scan.

This is true by default. When true, default settings of the table and family are used (this will never override caching blocks if the block cache is disabled for that family or entirely).

Overrides:

setCacheBlocks in class Scan

Parameters:

cacheBlocks - if false, default settings are overridden and blocks will not be cached

setReversed

public Scan setReversed(boolean reversed)

Description copied from class: Scan

Set whether this scan is a reversed one

This is false by default which means forward(normal) scan.

Overrides:

setReversed in class Scan

Parameters:

reversed - if true, scan will be backward order

Returns:

this

setAllowPartialResults

public Scan setAllowPartialResults(boolean allowPartialResults)

Description copied from class: Scan

Setting whether the caller wants to see the partial results when server returns less-than-expected cells. It is helpful while scanning a huge row to prevent OOM at client. By default this value is false and the complete results will be assembled client side before being delivered to the caller.

Overrides:

setAllowPartialResults in class Scan

Returns:

this

See Also:

Result.mayHaveMoreCellsInRow(), Scan.setBatch(int)

setLoadColumnFamiliesOnDemand

public Scan setLoadColumnFamiliesOnDemand(boolean value)

Description copied from class: Query

Set the value indicating whether loading CFs on demand should be allowed (cluster default is false). On-demand CF loading doesn't load column families until necessary, e.g. if you filter on one column, the other column family data will be loaded only for the rows that are included in result, not all rows like in normal case. With column-specific filters, like SingleColumnValueFilter w/filterIfMissing == true, this can deliver huge perf gains when there's a cf with lots of data; however, it can also lead to some inconsistent results, as follows: - if someone does a concurrent update to both column families in question you may get a row that never existed, e.g. for { rowKey = 5, { cat_videos => 1 }, { video => "my cat" } } someone puts rowKey 5 with { cat_videos => 0 }, { video => "my dog" }, concurrent scan filtering on "cat_videos == 1" can get { rowKey = 5, { cat_videos => 1 }, { video => "my dog" } }. - if there's a concurrent split and you have more than 2 column families, some rows may be missing some column families.

Overrides:

setLoadColumnFamiliesOnDemand in class Scan

setRaw

public Scan setRaw(boolean raw)

Description copied from class: Scan

Enable/disable "raw" mode for this scan. If "raw" is enabled the scan will return all delete marker and deleted rows that have not been collected, yet. This is mostly useful for Scan on column families that have KEEP_DELETED_ROWS enabled. It is an error to specify any column when "raw" is set.

Overrides:

setRaw in class Scan

Parameters:

raw - True/False to enable/disable "raw" mode.

setSmall

@Deprecated
public Scan setSmall(boolean small)

Deprecated.

Description copied from class: Scan

Set whether this scan is a small scan

Small scan should use pread and big scan can use seek + read seek + read is fast but can cause two problem (1) resource contention (2) cause too much network io [89-fb] Using pread for non-compaction read request https://issues.apache.org/jira/browse/HBASE-7266 On the other hand, if setting it true, we would do openScanner,next,closeScanner in one RPC call. It means the better performance for small scan. [HBASE-9488]. Generally, if the scan range is within one data block(64KB), it could be considered as a small scan.

Overrides:

setSmall in class Scan

See Also:

Scan.setLimit(int), Scan.setReadType(ReadType), HBASE-17045

setAttribute

public Scan setAttribute(String name,
                         byte[] value)

Description copied from interface: Attributes

Sets an attribute. In case value = null attribute is removed from the attributes map. Attribute names starting with _ indicate system attributes.

Specified by:

setAttribute in interface Attributes

Overrides:

setAttribute in class Scan

Parameters:

name - attribute name

value - attribute value

setId

public Scan setId(String id)

Description copied from class: OperationWithAttributes

This method allows you to set an identifier on an operation. The original motivation for this was to allow the identifier to be used in slow query logging, but this could obviously be useful in other places. One use of this could be to put a class.method identifier in here to see where the slow query is coming from.

Overrides:

setId in class Scan

Parameters:

id - id to set for the scan

setAuthorizations

public Scan setAuthorizations(Authorizations authorizations)

Description copied from class: Query

Sets the authorizations to be used by this Query

Overrides:

setAuthorizations in class Scan

setACL

public Scan setACL(Map<String,Permission> perms)

Overrides:

setACL in class Scan

Parameters:

perms - A map of permissions for a user or users

setACL

public Scan setACL(String user,
                   Permission perms)

Overrides:

setACL in class Scan

Parameters:

user - User short name

perms - Permissions for the user

setConsistency

public Scan setConsistency(Consistency consistency)

Description copied from class: Query

Sets the consistency level for this operation

Overrides:

setConsistency in class Scan

Parameters:

consistency - the consistency level

setReplicaId

public Scan setReplicaId(int id)

Description copied from class: Query

Specify region replica id where Query will fetch data from. Use this together with Query.setConsistency(Consistency) passing Consistency.TIMELINE to read data from a specific replicaId.
Expert: This is an advanced API exposed. Only use it if you know what you are doing

Overrides:

setReplicaId in class Scan

setIsolationLevel

public Scan setIsolationLevel(IsolationLevel level)

Description copied from class: Query

Set the isolation level for this query. If the isolation level is set to READ_UNCOMMITTED, then this query will return data from committed and uncommitted transactions. If the isolation level is set to READ_COMMITTED, then this query will return data from committed transactions only. If a isolation level is not explicitly set on a Query, then it is assumed to be READ_COMMITTED.

Overrides:

setIsolationLevel in class Scan

Parameters:

level - IsolationLevel for this query

setPriority

public Scan setPriority(int priority)

Overrides:

setPriority in class Scan

setScanMetricsEnabled

public Scan setScanMetricsEnabled(boolean enabled)

Description copied from class: Scan

Enable collection of ScanMetrics. For advanced users.

Overrides:

setScanMetricsEnabled in class Scan

Parameters:

enabled - Set to true to enable accumulating scan metrics

setAsyncPrefetch

@Deprecated
public Scan setAsyncPrefetch(boolean asyncPrefetch)

Deprecated.

Overrides:

setAsyncPrefetch in class Scan

setLimit

public Scan setLimit(int limit)

Description copied from class: Scan

Set the limit of rows for this scan. We will terminate the scan if the number of returned rows reaches this value.

This condition will be tested at last, after all other conditions such as stopRow, filter, etc.

Overrides:

setLimit in class Scan

Parameters:

limit - the limit of rows for this scan

Returns:

this

setOneRowLimit

public Scan setOneRowLimit()

Description copied from class: Scan

Call this when you only want to get one row. It will set limit to 1, and also set readType to Scan.ReadType.PREAD.

Overrides:

setOneRowLimit in class Scan

Returns:

this

setReadType

public Scan setReadType(Scan.ReadType readType)

Description copied from class: Scan

Set the read type for this scan.

Notice that we may choose to use pread even if you specific Scan.ReadType.STREAM here. For example, we will always use pread if this is a get scan.

Overrides:

setReadType in class Scan

Returns:

this

setNeedCursorResult

public Scan setNeedCursorResult(boolean needCursorResult)

Description copied from class: Scan

When the server is slow or we scan a table with many deleted data or we use a sparse filter, the server will response heartbeat to prevent timeout. However the scanner will return a Result only when client can do it. So if there are many heartbeats, the blocking time on ResultScanner#next() may be very long, which is not friendly to online services. Set this to true then you can get a special Result whose #isCursor() returns true and is not contains any real data. It only tells you where the server has scanned. You can call next to continue scanning or open a new scanner with this row key as start row whenever you want. Users can get a cursor when and only when there is a response from the server but we can not return a Result to users, for example, this response is a heartbeat or there are partial cells but users do not allow partial result. Now the cursor is in row level which means the special Result will only contains a row key. Result.isCursor() Result.getCursor() Cursor

Overrides:

setNeedCursorResult in class Scan

getMaxResultSize

public long getMaxResultSize()

Overrides:

getMaxResultSize in class Scan

Returns:

the maximum result size in bytes. See Scan.setMaxResultSize(long)

getFamilyMap

public Map<byte[],NavigableSet<byte[]>> getFamilyMap()

Description copied from class: Scan

Getting the familyMap

Overrides:

getFamilyMap in class Scan

Returns:

familyMap

numFamilies

public int numFamilies()

Overrides:

numFamilies in class Scan

Returns:

the number of families in familyMap

hasFamilies

public boolean hasFamilies()

Overrides:

hasFamilies in class Scan

Returns:

true if familyMap is non empty, false otherwise

getFamilies

public byte[][] getFamilies()

Overrides:

getFamilies in class Scan

Returns:

the keys of the familyMap

getStartRow

public byte[] getStartRow()

Overrides:

getStartRow in class Scan

Returns:

the startrow

includeStartRow

public boolean includeStartRow()

Overrides:

includeStartRow in class Scan

Returns:

if we should include start row when scan

getStopRow

public byte[] getStopRow()

Overrides:

getStopRow in class Scan

Returns:

the stoprow

includeStopRow

public boolean includeStopRow()

Overrides:

includeStopRow in class Scan

Returns:

if we should include stop row when scan

getMaxVersions

public int getMaxVersions()

Overrides:

getMaxVersions in class Scan

Returns:

the max number of versions to fetch

getBatch

public int getBatch()

Overrides:

getBatch in class Scan

Returns:

maximum number of values to return for a single call to next()

getMaxResultsPerColumnFamily

public int getMaxResultsPerColumnFamily()

Overrides:

getMaxResultsPerColumnFamily in class Scan

Returns:

maximum number of values to return per row per CF

getRowOffsetPerColumnFamily

public int getRowOffsetPerColumnFamily()

Description copied from class: Scan

Method for retrieving the scan's offset per row per column family (#kvs to be skipped)

Overrides:

getRowOffsetPerColumnFamily in class Scan

Returns:

row offset

getCaching

public int getCaching()

Overrides:

getCaching in class Scan

Returns:

caching the number of rows fetched when calling next on a scanner

getTimeRange

public TimeRange getTimeRange()

Overrides:

getTimeRange in class Scan

Returns:

TimeRange

getFilter

public Filter getFilter()

Overrides:

getFilter in class Scan

Returns:

RowFilter

hasFilter

public boolean hasFilter()

Overrides:

hasFilter in class Scan

Returns:

true is a filter has been specified, false if not

getCacheBlocks

public boolean getCacheBlocks()

Description copied from class: Scan

Get whether blocks should be cached for this Scan.

Overrides:

getCacheBlocks in class Scan

Returns:

true if default caching should be used, false if blocks should not be cached

isReversed

public boolean isReversed()

Description copied from class: Scan

Get whether this scan is a reversed one.

Overrides:

isReversed in class Scan

Returns:

true if backward scan, false if forward(default) scan

getAllowPartialResults

public boolean getAllowPartialResults()

Overrides:

getAllowPartialResults in class Scan

Returns:

true when the constructor of this scan understands that the results they will see may only represent a partial portion of a row. The entire row would be retrieved by subsequent calls to ResultScanner.next()

getACL

public byte[] getACL()

Overrides:

getACL in class Query

Returns:

The serialized ACL for this operation, or null if none

getFingerprint

public Map<String,Object> getFingerprint()

Description copied from class: Scan

Compile the table and column family (i.e. schema) information into a String. Useful for parsing and aggregation by debugging, logging, and administration tools.

Overrides:

getFingerprint in class Scan

Returns:

Map

toMap

public Map<String,Object> toMap(int maxCols)

Description copied from class: Scan

Compile the details beyond the scope of getFingerprint (row, columns, timestamps, etc.) into a Map along with the fingerprinted information. Useful for debugging, logging, and administration tools.

Overrides:

toMap in class Scan

Parameters:

maxCols - a limit on the number of columns output prior to truncation

Returns:

Map

isRaw

public boolean isRaw()

Overrides:

isRaw in class Scan

Returns:

True if this Scan is in "raw" mode.

isSmall

@Deprecated
public boolean isSmall()

Deprecated.

Description copied from class: Scan

Get whether this scan is a small scan

Overrides:

isSmall in class Scan

Returns:

true if small scan

See Also:

HBASE-17045

isScanMetricsEnabled

public boolean isScanMetricsEnabled()

Overrides:

isScanMetricsEnabled in class Scan

Returns:

True if collection of scan metrics is enabled. For advanced users.

isAsyncPrefetch

public Boolean isAsyncPrefetch()

Overrides:

isAsyncPrefetch in class Scan

getLimit

public int getLimit()

Overrides:

getLimit in class Scan

Returns:

the limit of rows for this scan

getReadType

public Scan.ReadType getReadType()

Overrides:

getReadType in class Scan

Returns:

the read type for this scan

isNeedCursorResult

public boolean isNeedCursorResult()

Overrides:

isNeedCursorResult in class Scan

getAttribute

public byte[] getAttribute(String name)

Description copied from interface: Attributes

Gets an attribute

Specified by:

getAttribute in interface Attributes

Overrides:

getAttribute in class OperationWithAttributes

Parameters:

name - attribute name

Returns:

attribute value if attribute is set, null otherwise

getConsistency

public Consistency getConsistency()

Description copied from class: Query

Returns the consistency level for this operation

Overrides:

getConsistency in class Query

Returns:

the consistency level

getAttributeSize

public long getAttributeSize()

Overrides:

getAttributeSize in class OperationWithAttributes

getAttributesMap

public Map<String,byte[]> getAttributesMap()

Description copied from interface: Attributes

Gets all attributes

Specified by:

getAttributesMap in interface Attributes

Overrides:

getAttributesMap in class OperationWithAttributes

Returns:

unmodifiable map of all attributes

getLoadColumnFamiliesOnDemandValue

public Boolean getLoadColumnFamiliesOnDemandValue()

Description copied from class: Query

Get the raw loadColumnFamiliesOnDemand setting; if it's not set, can be null.

Overrides:

getLoadColumnFamiliesOnDemandValue in class Query

getPriority

public int getPriority()

Overrides:

getPriority in class OperationWithAttributes

getColumnFamilyTimeRange

public Map<byte[],TimeRange> getColumnFamilyTimeRange()

Overrides:

getColumnFamilyTimeRange in class Query

Returns:

A map of column families to time ranges

getReplicaId

public int getReplicaId()

Description copied from class: Query

Returns region replica id where Query will fetch data from.

Overrides:

getReplicaId in class Query

Returns:

region replica id or -1 if not set.

doLoadColumnFamiliesOnDemand

public boolean doLoadColumnFamiliesOnDemand()

Description copied from class: Query

Get the logical value indicating whether on-demand CF loading should be allowed.

Overrides:

doLoadColumnFamiliesOnDemand in class Query

getId

public String getId()

Description copied from class: OperationWithAttributes

This method allows you to retrieve the identifier for the operation if one was set.

Overrides:

getId in class OperationWithAttributes

Returns:

the id or null if not set

isGetScan

public boolean isGetScan()

Overrides:

isGetScan in class Scan

getIsolationLevel

public IsolationLevel getIsolationLevel()

Overrides:

getIsolationLevel in class Query

Returns:

The isolation level of this query. If no isolation level was set for this query object, then it returns READ_COMMITTED.

getAuthorizations

public Authorizations getAuthorizations()
                                 throws DeserializationException

Overrides:

getAuthorizations in class Query

Returns:

The authorizations this Query is associated with.

Throws:

DeserializationException

toString

public String toString(int maxCols)

Description copied from class: Operation

Produces a string representation of this Operation. It defaults to a JSON representation, but falls back to a string representation of the fingerprint and details in the case of a JSON encoding failure.

Overrides:

toString in class Operation

Parameters:

maxCols - a limit on the number of columns output in the summary prior to truncation

Returns:

a JSON-parseable String

toString

public String toString()

Description copied from class: Operation

Produces a string representation of this Operation. It defaults to a JSON representation, but falls back to a string representation of the fingerprint and details in the case of a JSON encoding failure.

Overrides:

toString in class Operation

Returns:

String

toMap

public Map<String,Object> toMap()

Description copied from class: Operation

Produces a Map containing a full summary of a query.

Overrides:

toMap in class Operation

Returns:

a map containing parameters of a query (i.e. rows, columns...)

toJSON

public String toJSON(int maxCols)
              throws IOException

Description copied from class: Operation

Produces a JSON object for fingerprint and details exposure in a parseable format.

Overrides:

toJSON in class Operation

Parameters:

maxCols - a limit on the number of columns to include in the JSON

Returns:

a JSONObject containing this Operation's information, as a string

Throws:

IOException

toJSON

public String toJSON()
              throws IOException

Description copied from class: Operation

Produces a JSON object sufficient for description of a query in a debugging or logging context.

Overrides:

toJSON in class Operation

Returns:

the produced JSON object, as a string

Throws:

IOException