oracle.spatial.hadoop.vector.mapreduce

Class AbstractSpatialHierarchicalMapper<K,V,W>

java.lang.Object

org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.io.Text,RTreeWritable,org.apache.hadoop.io.Text,W>

oracle.spatial.hadoop.vector.mapreduce.AbstractSpatialHierarchicalMapper<K,V,W>

Type Parameters:

K - The type of the internalInputFormat's keys

V - The type of the internalInputFormat's values

W - The type of the output value

Direct Known Subclasses:

SpatialHierarchicalCountMapper, SpatialHierarchicalJoinMapper

public abstract class AbstractSpatialHierarchicalMapper<K,V,W>
extends org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.io.Text,RTreeWritable,org.apache.hadoop.io.Text,W>

Base mapper class used to catalog records into hierarchy layers. Records are cataloged using a spatial operation between the record's geometry and the geometries of the hierarchical entities.

The input data is always expected to be a spatial index as generated by SpatialIndexingMapper

The output key is a combination of a hierarchy layer's name and one of the id of one of the hierarchy level's entities. The value must be defined by the implementing class

The search always starts from the bottom level of the hierarchy, that is, the maximum hierarchy level. As matches are found, the counts are propagated to the parents in upper levels. By default, only the bottom level entries are searched in the spatial index, however, by setting to true the parameter ConfigParams.HIERARCHY_SEARCH_MULTIPLE_LEVELS it is possible to continue searching in upper hierarchies until all the elements in the index are cataloged.

Expected configuration:

• ConfigParams.HIERARCHY_INFO_CLASS
• ConfigParams.HIERARCHY_LOAD_MIN_LEVEL - optional
• ConfigParams.HIERARCHY_LOAD_MAX_LEVEL - optional
• ConfigParams.HIERARCHY_SEARCH_MULTIPLE_LEVELS - optional
• ConfigParams.SPATIAL_OPERATION
• ConfigParams.SRID
• ConfigParams.SPATIAL_TOLERANCE - optional
• ConfigParams.GEODETIC

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.mapreduce.Mapper

org.apache.hadoop.mapreduce.Mapper.Context

Field Summary

Fields

Modifier and Type	Field and Description
protected HierarchyInfo	hierInfo
protected int	maxLevel
protected int	minLevel
protected org.apache.hadoop.io.Text	outKey
protected boolean	searchMultiLevels
protected SpatialOperationConfig	spatialOpConf

Constructor Summary

Constructors

Constructor and Description
AbstractSpatialHierarchicalMapper()

Method Summary

Modifier and Type	Method and Description
protected abstract W	getOutValue(RecordInfo matchingRecordInfo) Given a RecordInfo instance representing a record that previously matched a hierarchy entry, returns the output value
protected void	map(org.apache.hadoop.io.Text key, RTreeWritable value, org.apache.hadoop.mapreduce.Mapper.Context context)
protected void	mapHierarchicalResults(java.lang.String featureId, int level, W outValue, org.apache.hadoop.mapreduce.Mapper.Context context)
void	setup(org.apache.hadoop.mapreduce.Mapper.Context context)

Methods inherited from class org.apache.hadoop.mapreduce.Mapper

cleanup, run

Methods inherited from class java.lang.Object

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

Field Detail

outKey

protected org.apache.hadoop.io.Text outKey

spatialOpConf

protected SpatialOperationConfig spatialOpConf

hierInfo

protected HierarchyInfo hierInfo

searchMultiLevels

protected boolean searchMultiLevels

maxLevel

protected int maxLevel

minLevel

protected int minLevel

Constructor Detail

AbstractSpatialHierarchicalMapper

public AbstractSpatialHierarchicalMapper()

Method Detail

setup

public void setup(org.apache.hadoop.mapreduce.Mapper.Context context)
           throws java.io.IOException,
                  java.lang.InterruptedException

Overrides:

setup in class org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.io.Text,RTreeWritable,org.apache.hadoop.io.Text,W>

Throws:

java.io.IOException

java.lang.InterruptedException

map

protected void map(org.apache.hadoop.io.Text key,
                   RTreeWritable value,
                   org.apache.hadoop.mapreduce.Mapper.Context context)
            throws java.io.IOException,
                   java.lang.InterruptedException

Overrides:

map in class org.apache.hadoop.mapreduce.Mapper<org.apache.hadoop.io.Text,RTreeWritable,org.apache.hadoop.io.Text,W>

Throws:

java.io.IOException

java.lang.InterruptedException

getOutValue

protected abstract W getOutValue(RecordInfo matchingRecordInfo)

Given a RecordInfo instance representing a record that previously matched a hierarchy entry, returns the output value

Parameters:

matchingRecordInfo - an instance of RecordInfo

Returns:

a value used as the output value

mapHierarchicalResults

protected void mapHierarchicalResults(java.lang.String featureId,
                                      int level,
                                      W outValue,
                                      org.apache.hadoop.mapreduce.Mapper.Context context)
                               throws java.io.IOException,
                                      java.lang.InterruptedException

Throws:

java.io.IOException

java.lang.InterruptedException