InputTableConfig (Apache Accumulo Project 1.7.4 API)

java.lang.Object
- org.apache.accumulo.core.client.mapreduce.InputTableConfig

All Implemented Interfaces:

org.apache.hadoop.io.Writable
```
public class InputTableConfig
extends Object
implements org.apache.hadoop.io.Writable
```
This class to holds a batch scan configuration for a table. It contains all the properties needed to specify how rows should be returned from the table.

Constructor Summary

Constructors
Constructor and Description

InputTableConfig()

InputTableConfig(DataInput input)
Creates a batch scan config object out of a previously serialized batch scan config object.

Constructors
Constructor and Description
`InputTableConfig()`
`InputTableConfig(DataInput input)` Creates a batch scan config object out of a previously serialized batch scan config object.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`equals(Object o)`
`InputTableConfig`	`fetchColumns(Collection<org.apache.accumulo.core.util.Pair<org.apache.hadoop.io.Text,org.apache.hadoop.io.Text>> columns)` Restricts the columns that will be mapped over for this job for the default input table.
`Collection<org.apache.accumulo.core.util.Pair<org.apache.hadoop.io.Text,org.apache.hadoop.io.Text>>`	`getFetchedColumns()` Returns the columns to be fetched for this configuration
`List<IteratorSetting>`	`getIterators()` Returns the iterators to be set on this configuration
`List<Range>`	`getRanges()` Returns the ranges to be queried in the configuration
`int`	`hashCode()`
`boolean`	`isOfflineScan()` Determines whether a configuration has the offline table scan feature enabled.
`void`	`readFields(DataInput dataInput)`
`InputTableConfig`	`setAutoAdjustRanges(boolean autoAdjustRanges)` Controls the automatic adjustment of ranges for this job.
`InputTableConfig`	`setIterators(List<IteratorSetting> iterators)` Set iterators on to be used in the query.
`InputTableConfig`	`setOfflineScan(boolean offlineScan)` Enable reading offline tables.
`InputTableConfig`	`setRanges(List<Range> ranges)` Sets the input ranges to scan for all tables associated with this job.
`InputTableConfig`	`setUseIsolatedScanners(boolean useIsolatedScanners)` Controls the use of the `IsolatedScanner` in this job.
`InputTableConfig`	`setUseLocalIterators(boolean useLocalIterators)` Controls the use of the `ClientSideIteratorScanner` in this job.
`boolean`	`shouldAutoAdjustRanges()` Determines whether a configuration has auto-adjust ranges enabled.
`boolean`	`shouldUseIsolatedScanners()` Determines whether a configuration has isolation enabled.
`boolean`	`shouldUseLocalIterators()` Determines whether a configuration uses local iterators.
`void`	`write(DataOutput dataOutput)`

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - InputTableConfig
```
public InputTableConfig()
```
  - InputTableConfig
```
public InputTableConfig(DataInput input)
                 throws IOException
```
    Creates a batch scan config object out of a previously serialized batch scan config object.
    
    Parameters:
    
    input - the data input of the serialized batch scan config
    
    Throws:
    
    IOException
- Method Detail
  - setRanges
```
public InputTableConfig setRanges(List<Range> ranges)
```
    Sets the input ranges to scan for all tables associated with this job. This will be added to any per-table ranges that have been set using
    
    Parameters:
    
    ranges - the ranges that will be mapped over
    
    Since:
    
    1.6.0
  - getRanges
```
public List<Range> getRanges()
```
    Returns the ranges to be queried in the configuration
  - fetchColumns
```
public InputTableConfig fetchColumns(Collection<org.apache.accumulo.core.util.Pair<org.apache.hadoop.io.Text,org.apache.hadoop.io.Text>> columns)
```
    Restricts the columns that will be mapped over for this job for the default input table.
    
    Parameters:
    
    columns - a pair of Text objects corresponding to column family and column qualifier. If the column qualifier is null, the entire column family is selected. An empty set is the default and is equivalent to scanning the all columns.
    
    Since:
    
    1.6.0
  - getFetchedColumns
```
public Collection<org.apache.accumulo.core.util.Pair<org.apache.hadoop.io.Text,org.apache.hadoop.io.Text>> getFetchedColumns()
```
    Returns the columns to be fetched for this configuration
  - setIterators
```
public InputTableConfig setIterators(List<IteratorSetting> iterators)
```
    Set iterators on to be used in the query.
    
    Parameters:
    
    iterators - the configurations for the iterators
    
    Since:
    
    1.6.0
  - getIterators
```
public List<IteratorSetting> getIterators()
```
    Returns the iterators to be set on this configuration
  - setAutoAdjustRanges
```
public InputTableConfig setAutoAdjustRanges(boolean autoAdjustRanges)
```
    Controls the automatic adjustment of ranges for this job. This feature merges overlapping ranges, then splits them to align with tablet boundaries. Disabling this feature will cause exactly one Map task to be created for each specified range. The default setting is enabled. *
    By default, this feature is enabled.
    
    Parameters:
    
    autoAdjustRanges - the feature is enabled if true, disabled otherwise
    
    Since:
    
    1.6.0
    
    See Also:
    
    setRanges(java.util.List)
  - shouldAutoAdjustRanges
```
public boolean shouldAutoAdjustRanges()
```
    Determines whether a configuration has auto-adjust ranges enabled.
    
    Returns:
    
    false if the feature is disabled, true otherwise
    
    Since:
    
    1.6.0
    
    See Also:
    
    setAutoAdjustRanges(boolean)
  - setUseLocalIterators
```
public InputTableConfig setUseLocalIterators(boolean useLocalIterators)
```
    Controls the use of the ClientSideIteratorScanner in this job. Enabling this feature will cause the iterator stack to be constructed within the Map task, rather than within the Accumulo TServer. To use this feature, all classes needed for those iterators must be available on the classpath for the task.
    By default, this feature is disabled.
    
    Parameters:
    
    useLocalIterators - the feature is enabled if true, disabled otherwise
    
    Since:
    
    1.6.0
  - shouldUseLocalIterators
```
public boolean shouldUseLocalIterators()
```
    Determines whether a configuration uses local iterators.
    
    Returns:
    
    true if the feature is enabled, false otherwise
    
    Since:
    
    1.6.0
    
    See Also:
    
    setUseLocalIterators(boolean)
  - setOfflineScan
```
public InputTableConfig setOfflineScan(boolean offlineScan)
```
    Enable reading offline tables. By default, this feature is disabled and only online tables are scanned. This will make the map reduce job directly read the table's files. If the table is not offline, then the job will fail. If the table comes online during the map reduce job, it is likely that the job will fail.
    To use this option, the map reduce user will need access to read the Accumulo directory in HDFS.
    Reading the offline table will create the scan time iterator stack in the map process. So any iterators that are configured for the table will need to be on the mapper's classpath. The accumulo-site.xml may need to be on the mapper's classpath if HDFS or the Accumulo directory in HDFS are non-standard.
    One way to use this feature is to clone a table, take the clone offline, and use the clone as the input table for a map reduce job. If you plan to map reduce over the data many times, it may be better to the compact the table, clone it, take it offline, and use the clone for all map reduce jobs. The reason to do this is that compaction will reduce each tablet in the table to one file, and it is faster to read from one file.
    There are two possible advantages to reading a tables file directly out of HDFS. First, you may see better read performance. Second, it will support speculative execution better. When reading an online table speculative execution can put more load on an already slow tablet server.
    By default, this feature is disabled.
    
    Parameters:
    
    offlineScan - the feature is enabled if true, disabled otherwise
    
    Since:
    
    1.6.0
  - isOfflineScan
```
public boolean isOfflineScan()
```
    Determines whether a configuration has the offline table scan feature enabled.
    
    Returns:
    
    true if the feature is enabled, false otherwise
    
    Since:
    
    1.6.0
    
    See Also:
    
    setOfflineScan(boolean)
  - setUseIsolatedScanners
```
public InputTableConfig setUseIsolatedScanners(boolean useIsolatedScanners)
```
    Controls the use of the IsolatedScanner in this job.
    By default, this feature is disabled.
    
    Parameters:
    
    useIsolatedScanners - the feature is enabled if true, disabled otherwise
    
    Since:
    
    1.6.0
  - shouldUseIsolatedScanners
```
public boolean shouldUseIsolatedScanners()
```
    Determines whether a configuration has isolation enabled.
    
    Returns:
    
    true if the feature is enabled, false otherwise
    
    Since:
    
    1.6.0
    
    See Also:
    
    setUseIsolatedScanners(boolean)
  - write
```
public void write(DataOutput dataOutput)
           throws IOException
```
    Specified by:
    
    write in interface org.apache.hadoop.io.Writable
    
    Throws:
    
    IOException
  - readFields
```
public void readFields(DataInput dataInput)
                throws IOException
```
    Specified by:
    
    readFields in interface org.apache.hadoop.io.Writable
    
    Throws:
    
    IOException
  - equals
```
public boolean equals(Object o)
```
    Overrides:
    
    equals in class Object
  - hashCode
```
public int hashCode()
```
    Overrides:
    
    hashCode in class Object

Class InputTableConfig

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

InputTableConfig

InputTableConfig

Method Detail

setRanges

getRanges

fetchColumns

getFetchedColumns

setIterators

getIterators

setAutoAdjustRanges

shouldAutoAdjustRanges

setUseLocalIterators

shouldUseLocalIterators

setOfflineScan

isOfflineScan

setUseIsolatedScanners

shouldUseIsolatedScanners

write

readFields

equals

hashCode