org.geotools.feature.visitor
Class MaxVisitor

java.lang.Object
  org.geotools.feature.visitor.MaxVisitor

All Implemented Interfaces:

FeatureCalc, FeatureVisitor

public class MaxVisitor

extends java.lang.Object

implements FeatureCalc

Calculates the maximum value of an attribute.

Since:

2.2.M2

Author:

Cory Horner, Refractions Research Inc.

Nested Class Summary

static class

MaxVisitor.MaxResult

Constructor Summary

MaxVisitor(Expression expr)

MaxVisitor(int attributeTypeIndex, FeatureType type)

MaxVisitor(java.lang.String attrName, FeatureType type)

Method Summary

Expression	getExpression()
java.lang.Comparable	getMax() Get the max value.
int	getNaNCount()
int	getNullCount()
CalcResult	getResult() Returns the result of the calculation as a handy object which can be merged and modified.
void	reset()
void	setValue(java.lang.Object result) Overwrites the result stored by the visitor.
void	visit(Feature feature) Visitor function, which looks at each feature and finds the maximum.

Methods inherited from class java.lang.Object

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

Constructor Detail

MaxVisitor

public MaxVisitor(int attributeTypeIndex,
                  FeatureType type)
           throws IllegalFilterException

MaxVisitor

public MaxVisitor(java.lang.String attrName,
                  FeatureType type)
           throws IllegalFilterException

MaxVisitor

public MaxVisitor(Expression expr)
           throws IllegalFilterException

Method Detail

visit

public void visit(Feature feature)

Visitor function, which looks at each feature and finds the maximum.

Specified by:

visit in interface FeatureVisitor

Parameters:

feature - the feature to be visited

getMax

public java.lang.Comparable getMax()

Get the max value.

Returns:

Max value

Throws:

java.lang.IllegalStateException - DOCUMENT ME!

getNaNCount

public int getNaNCount()

Returns:

the number of features which returned a NaN

getNullCount

public int getNullCount()

Returns:

the number of features which returned a null

reset

public void reset()

getExpression

public Expression getExpression()

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

setValue

public void setValue(java.lang.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 'max', the value stored is of type 'Comparable'.

Parameters:

result -