org.geotools.feature.visitor

Class UniqueVisitor

Object

UniqueVisitor

All Implemented Interfaces:

FeatureAttributeVisitor, FeatureCalc, LimitingVisitor, FeatureVisitor

public class UniqueVisitor
extends Object
implements FeatureCalc, FeatureAttributeVisitor, LimitingVisitor

Generates a list of unique values from a collection

Since:

2.2.M2

Author:

Cory Horner, Refractions

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	UniqueVisitor.UniqueResult

Constructor Summary

Constructors

Constructor and Description
UniqueVisitor(Expression expr)
UniqueVisitor(int attributeTypeIndex, SimpleFeatureType type)
UniqueVisitor(String attributeTypeName)
UniqueVisitor(String attrName, SimpleFeatureType type)

Method Summary

Modifier and Type	Method and Description
Expression	getExpression()
List<Expression>	getExpressions() List of expressions used by visitor.
int	getMaxFeatures() Returns maxFeatures (max # of elements to return)
CalcResult	getResult() Returns the result of the calculation as a handy object which can be merged and modified.
Optional<List<Class>>	getResultType(List<Class> inputTypes) Returns the expected output type given the input type.
int	getStartIndex() Returns startIndex (first element to return)
Set	getUnique()
boolean	hasLimits() Checks if the visitor has limits.
void	init(SimpleFeatureCollection collection)
boolean	isPreserveOrder() True if the unique visitor must be order preserving
void	reset()
void	setMaxFeatures(int maxFeatures)
void	setPreserveOrder(boolean preserveOrder)
void	setStartIndex(int startIndex)
void	setValue(Object newSet)
void	visit(Feature feature) Visit the provided feature.
void	visit(SimpleFeature feature)

Methods inherited from class Object

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

Constructor Detail

UniqueVisitor

public UniqueVisitor(String attributeTypeName)

UniqueVisitor

public UniqueVisitor(int attributeTypeIndex,
                     SimpleFeatureType type)
              throws IllegalFilterException

Throws:

IllegalFilterException

UniqueVisitor

public UniqueVisitor(String attrName,
                     SimpleFeatureType type)
              throws IllegalFilterException

Throws:

IllegalFilterException

UniqueVisitor

public UniqueVisitor(Expression expr)

Method Detail

init

public void init(SimpleFeatureCollection collection)

setStartIndex

public void setStartIndex(int startIndex)

setMaxFeatures

public void setMaxFeatures(int maxFeatures)

setPreserveOrder

public void setPreserveOrder(boolean preserveOrder)

getStartIndex

public int getStartIndex()

Description copied from interface: LimitingVisitor

Returns startIndex (first element to return)

Specified by:

getStartIndex in interface LimitingVisitor

getMaxFeatures

public int getMaxFeatures()

Description copied from interface: LimitingVisitor

Returns maxFeatures (max # of elements to return)

Specified by:

getMaxFeatures in interface LimitingVisitor

getExpressions

public List<Expression> getExpressions()

Description copied from interface: FeatureAttributeVisitor

List of expressions used by visitor.

Specified by:

getExpressions in interface FeatureAttributeVisitor

getResultType

public Optional<List<Class>> getResultType(List<Class> inputTypes)

Description copied from interface: FeatureAttributeVisitor

Returns the expected output type given the input type.

Specified by:

getResultType in interface FeatureAttributeVisitor

Parameters:

inputTypes - The type of the input expressions

visit

public void visit(SimpleFeature feature)

visit

public void visit(Feature feature)

Description copied from interface: FeatureVisitor

Visit the provided feature.

Please consult the documentation for the FeatureCollection you are visiting to learn more - the provided feature may be invalid, or read only.

Specified by:

visit in interface FeatureVisitor

getExpression

public Expression getExpression()

getUnique

public Set getUnique()

setValue

public void setValue(Object newSet)

reset

public void reset()

getResult

public CalcResult getResult()

Description copied from interface: FeatureCalc

Returns the result of the calculation as a handy object which can be merged and modified.

Specified by:

getResult in interface FeatureCalc

Returns:

the results of the calculation

hasLimits

public boolean hasLimits()

Description copied from interface: LimitingVisitor

Checks if the visitor has limits.

Specified by:

hasLimits in interface LimitingVisitor

Returns:

true if the visitor has limits

isPreserveOrder

public boolean isPreserveOrder()

True if the unique visitor must be order preserving