DataRange (apache-cassandra API)

java.lang.Object
- org.apache.cassandra.db.DataRange

Direct Known Subclasses:

DataRange.Paging
```
public class DataRange
extends java.lang.Object
```
Groups both the range of partitions to query, and the clustering index filter to apply for each partition (for a (partition) range query).
The main "trick" is that the clustering index filter can only be obtained by providing the partition key on which the filter will be applied. This is necessary when paging range queries, as we might need a different filter for the starting key than for other keys (because the previous page we had queried may have ended in the middle of a partition).

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class DataRange.Paging
Specialized DataRange used for the paging case.

static class DataRange.Serializer

Nested Classes
Modifier and Type	Class and Description
`static class`	`DataRange.Paging` Specialized `DataRange` used for the paging case.
`static class`	`DataRange.Serializer`

Field Summary

Fields
Modifier and Type	Field and Description
`protected ClusteringIndexFilter`	`clusteringIndexFilter`
`protected AbstractBounds<PartitionPosition>`	`keyRange`
`static DataRange.Serializer`	`serializer`

Constructor Summary

Constructors
Constructor and Description
`DataRange(AbstractBounds<PartitionPosition> range, ClusteringIndexFilter clusteringIndexFilter)` Creates a `DataRange` given a range of partition keys and a clustering index filter.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`static DataRange`	`allData(IPartitioner partitioner)` Creates a `DataRange` to query all data (over the whole ring).
`static DataRange`	`allData(IPartitioner partitioner, ClusteringIndexFilter filter)` Creates a `DataRange` to query all partitions of the ring using the provided clustering index filter.
`static void`	`appendKeyString(java.lang.StringBuilder sb, AbstractType<?> type, java.nio.ByteBuffer key)`
`ClusteringIndexFilter`	`clusteringIndexFilter(DecoratedKey key)` The clustering index filter to use for the provided key.
`boolean`	`contains(PartitionPosition pos)` Whether the provided ring position is covered by this `DataRange`.
`static DataRange`	`forKeyRange(Range<PartitionPosition> keyRange)` Creates a `DataRange` to query all rows over the provided key range.
`DataRange`	`forPaging(AbstractBounds<PartitionPosition> range, ClusteringComparator comparator, Clustering<?> lastReturned, boolean inclusive)` Returns a new `DataRange` for use when paging `this` range.
`DataRange`	`forSubRange(AbstractBounds<PartitionPosition> range)` Returns a new `DataRange` equivalent to `this` one but restricted to the provided sub-range.
`static DataRange`	`forTokenRange(Range<Token> tokenRange)` Creates a `DataRange` to query all rows over the provided token range.
`boolean`	`isNamesQuery()` Whether the underlying clustering index filter is a names filter or not.
`boolean`	`isPaging()` Whether the data range is for a paged request or not.
`boolean`	`isReversed()` Whether the underlying `ClusteringIndexFilter` is reversed or not.
`boolean`	`isUnrestricted()` Whether this `DataRange` queries everything (has no restriction neither on the partition queried, nor within the queried partition).
`boolean`	`isWrapAround()` Whether the range queried by this `DataRange` actually wraps around.
`AbstractBounds<PartitionPosition>`	`keyRange()` The range of partition key queried by this `DataRange`.
`boolean`	`selectsAllPartition()`
`PartitionPosition`	`startKey()` The start of the partition key range queried by this `DataRange`.
`PartitionPosition`	`stopKey()` The end of the partition key range queried by this `DataRange`.
`java.lang.String`	`toCQLString(TableMetadata metadata)`
`java.lang.String`	`toString(TableMetadata metadata)`

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

- Field Detail
  - serializer
```
public static final DataRange.Serializer serializer
```
  - keyRange
```
protected final AbstractBounds<PartitionPosition> keyRange
```
  - clusteringIndexFilter
```
protected final ClusteringIndexFilter clusteringIndexFilter
```
- Constructor Detail
  - DataRange
```
public DataRange(AbstractBounds<PartitionPosition> range,
                 ClusteringIndexFilter clusteringIndexFilter)
```
    Creates a DataRange given a range of partition keys and a clustering index filter. The return DataRange will return the same filter for all keys.
    
    Parameters:
    
    range - the range over partition keys to use.
    
    clusteringIndexFilter - the clustering index filter to use.
- Method Detail
  - allData
```
public static DataRange allData(IPartitioner partitioner)
```
    Creates a DataRange to query all data (over the whole ring).
    
    Parameters:
    
    partitioner - the partitioner in use for the table.
    
    Returns:
    
    the newly create DataRange.
  - forTokenRange
```
public static DataRange forTokenRange(Range<Token> tokenRange)
```
    Creates a DataRange to query all rows over the provided token range.
    
    Parameters:
    
    tokenRange - the (partition key) token range to query.
    
    Returns:
    
    the newly create DataRange.
  - forKeyRange
```
public static DataRange forKeyRange(Range<PartitionPosition> keyRange)
```
    Creates a DataRange to query all rows over the provided key range.
    
    Parameters:
    
    keyRange - the (partition key) range to query.
    
    Returns:
    
    the newly create DataRange.
  - allData
```
public static DataRange allData(IPartitioner partitioner,
                                ClusteringIndexFilter filter)
```
    Creates a DataRange to query all partitions of the ring using the provided clustering index filter.
    
    Parameters:
    
    partitioner - the partitioner in use for the table queried.
    
    filter - the clustering index filter to use.
    
    Returns:
    
    the newly create DataRange.
  - keyRange
```
public AbstractBounds<PartitionPosition> keyRange()
```
    The range of partition key queried by this DataRange.
    
    Returns:
    
    the range of partition key queried by this DataRange.
  - startKey
```
public PartitionPosition startKey()
```
    The start of the partition key range queried by this DataRange.
    
    Returns:
    
    the start of the partition key range queried by this DataRange.
  - stopKey
```
public PartitionPosition stopKey()
```
    The end of the partition key range queried by this DataRange.
    
    Returns:
    
    the end of the partition key range queried by this DataRange.
  - isNamesQuery
```
public boolean isNamesQuery()
```
    Whether the underlying clustering index filter is a names filter or not.
    
    Returns:
    
    Whether the underlying clustering index filter is a names filter or not.
  - isPaging
```
public boolean isPaging()
```
    Whether the data range is for a paged request or not.
    
    Returns:
    
    true if for paging, false otherwise
  - isWrapAround
```
public boolean isWrapAround()
```
    Whether the range queried by this DataRange actually wraps around.
    
    Returns:
    
    whether the range queried by this DataRange actually wraps around.
  - contains
```
public boolean contains(PartitionPosition pos)
```
    Whether the provided ring position is covered by this DataRange.
    
    Returns:
    
    whether the provided ring position is covered by this DataRange.
  - isUnrestricted
```
public boolean isUnrestricted()
```
    Whether this DataRange queries everything (has no restriction neither on the partition queried, nor within the queried partition).
    
    Returns:
    
    Whether this DataRange queries everything.
  - selectsAllPartition
```
public boolean selectsAllPartition()
```
  - isReversed
```
public boolean isReversed()
```
    Whether the underlying ClusteringIndexFilter is reversed or not.
    
    Returns:
    
    whether the underlying ClusteringIndexFilter is reversed or not.
  - clusteringIndexFilter
```
public ClusteringIndexFilter clusteringIndexFilter(DecoratedKey key)
```
    The clustering index filter to use for the provided key.
    This may or may not be the same filter for all keys (that is, paging range use a different filter for their start key).
    
    Parameters:
    
    key - the partition key for which we want the clustering index filter.
    
    Returns:
    
    the clustering filter to use for key.
  - forPaging
```
public DataRange forPaging(AbstractBounds<PartitionPosition> range,
                           ClusteringComparator comparator,
                           Clustering<?> lastReturned,
                           boolean inclusive)
```
    Returns a new DataRange for use when paging this range.
    
    Parameters:
    
    range - the range of partition keys to query.
    
    comparator - the comparator for the table queried.
    
    lastReturned - the clustering for the last result returned by the previous page, i.e. the result we want to start our new page from. This last returned must correspond to left bound of range (in other words, range.left must be the partition key for that lastReturned result).
    
    inclusive - whether or not we want to include the lastReturned in the newly returned page of results.
    
    Returns:
    
    a new DataRange suitable for paging this range given the lastRetuned result of the previous page.
  - forSubRange
```
public DataRange forSubRange(AbstractBounds<PartitionPosition> range)
```
    Returns a new DataRange equivalent to this one but restricted to the provided sub-range.
    
    Parameters:
    
    range - the sub-range to use for the newly returned data range. Note that assumes that range is a proper sub-range of the initial range but doesn't validate it. You should make sure to only provided sub-ranges however or this might throw off the paging case (see Paging.forSubRange()).
    
    Returns:
    
    a new DataRange using range as partition key range and the clustering index filter filter from this.
  - toString
```
public java.lang.String toString(TableMetadata metadata)
```
  - toCQLString
```
public java.lang.String toCQLString(TableMetadata metadata)
```
  - appendKeyString
```
public static void appendKeyString(java.lang.StringBuilder sb,
                                   AbstractType<?> type,
                                   java.nio.ByteBuffer key)
```

Class DataRange

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

serializer

keyRange

clusteringIndexFilter

Constructor Detail

DataRange

Method Detail

allData

forTokenRange

forKeyRange

allData

keyRange

startKey

stopKey

isNamesQuery

isPaging

isWrapAround

contains

isUnrestricted

selectsAllPartition

isReversed

clusteringIndexFilter

forPaging

forSubRange

toString

toCQLString

appendKeyString