org.geotools.feature.visitor
Class MinVisitor

Object
  extended by MinVisitor
All Implemented Interfaces:
FeatureCalc, FeatureVisitor

public class MinVisitor
extends Object
implements FeatureCalc

Calculates the minimum value of an attribute.

Since:
2.2.M2
Author:
Cory Horner, Refractions
Module:
modules/library/main (gt-main.jar)

Nested Class Summary
static class MinVisitor.MinResult
           
 
Constructor Summary
MinVisitor(Expression expr)
           
MinVisitor(int attributeTypeIndex, SimpleFeatureType type)
           
MinVisitor(String attributeTypeName)
           
MinVisitor(String attrName, SimpleFeatureType type)
           
 
Method Summary
 Expression getExpression()
           
 Comparable getMin()
          Get the min value.
 CalcResult getResult()
          Returns the result of the calculation as a handy object which can be merged and modified.
 void init(FeatureCollection<SimpleFeatureType,SimpleFeature> collection)
           
 void reset()
           
 void setValue(Object result)
          Overwrites the result stored by the visitor.
 void visit(Feature feature)
           
 void visit(SimpleFeature feature)
          Visitor function, which looks at each feature and finds the minimum.
 
Methods inherited from class Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

MinVisitor

public MinVisitor(String attributeTypeName)

MinVisitor

public MinVisitor(int attributeTypeIndex,
                  SimpleFeatureType type)
           throws IllegalFilterException
Throws:
IllegalFilterException

MinVisitor

public MinVisitor(String attrName,
                  SimpleFeatureType type)
           throws IllegalFilterException
Throws:
IllegalFilterException

MinVisitor

public MinVisitor(Expression expr)
           throws IllegalFilterException
Throws:
IllegalFilterException
Method Detail

init

public void init(FeatureCollection<SimpleFeatureType,SimpleFeature> collection)

visit

public void visit(SimpleFeature feature)
Visitor function, which looks at each feature and finds the minimum.

Parameters:
feature - the feature to be visited

visit

public void visit(Feature feature)
Specified by:
visit in interface FeatureVisitor

getMin

public Comparable getMin()
Get the min value.

Returns:
Minimum value
Throws:
IllegalStateException - DOCUMENT ME!

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

getExpression

public Expression getExpression()

setValue

public void setValue(Object result)
Overwrites the result stored by the visitor. This should only be used by optimizations which will tell the visitor the answer rather than visiting all features.

For 'min', the value stored is of type 'Comparable'.

Parameters:
result -


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