org.geotools.filter.function
Class Collection_MedianFunction
Object
ExpressionAbstract
DefaultExpression
FunctionExpressionImpl
Collection_MedianFunction
- All Implemented Interfaces:
- Factory, ExpressionType, FunctionExpression, Expression, Function
public class Collection_MedianFunction
- extends FunctionExpressionImpl
- implements FunctionExpression
Calculates the median value of an attribute for a given FeatureCollection
and Expression.
- Since:
- 2.2M2
- Author:
- Cory Horner
- Module:
Fields inherited from interface ExpressionType |
ATTRIBUTE, ATTRIBUTE_DOUBLE, ATTRIBUTE_GEOMETRY, ATTRIBUTE_INTEGER, ATTRIBUTE_STRING, ATTRIBUTE_UNDECLARED, FUNCTION, LITERAL_DOUBLE, LITERAL_GEOMETRY, LITERAL_INTEGER, LITERAL_LONG, LITERAL_STRING, LITERAL_UNDECLARED, MATH_ADD, MATH_DIVIDE, MATH_MULTIPLY, MATH_SUBTRACT |
Fields inherited from interface Expression |
NIL |
Fields inherited from interface Expression |
NIL |
Methods inherited from class FunctionExpressionImpl |
accept, equals, getArgs, getExpression, getFallbackValue, getImplementationHints, getName, getParameters, getType, setArgs, setFallbackValue, setName, toString |
Methods inherited from interface Expression |
accept, evaluate |
Methods inherited from interface Function |
getFallbackValue, getParameters |
Methods inherited from interface Expression |
accept, evaluate |
Collection_MedianFunction
public Collection_MedianFunction()
- Creates a new instance of Collection_MedianFunction
getArgCount
public int getArgCount()
- Description copied from class:
FunctionExpressionImpl
- Gets the number of arguments that are set.
- Specified by:
getArgCount
in interface FunctionExpression
- Specified by:
getArgCount
in class FunctionExpressionImpl
- Returns:
- the number of args.
setParameters
public void setParameters(List args)
- The provided arguments are evaulated with respect to the
FeatureCollection.
For an aggregate function (like median) please use the WFS mandated XPath
syntax to refer to featureMember content.
To refer to all 'X': featureMember/asterisk/X
- Specified by:
setParameters
in interface FunctionExpression
- Overrides:
setParameters
in class FunctionExpressionImpl
- Parameters:
args
- DOCUMENT ME!
- Throws:
IllegalArgumentException
- DOCUMENT ME!
evaluate
public Object evaluate(Object feature)
- Description copied from class:
DefaultExpression
- This method checks if the object is an instance of
Feature
and
if so, calls through to #evaluate(Feature)
. This is done
to maintain backwards compatability with previous version of Expression api
which depended on Feature. If the object is not an instance of feature
the super implementation is called.
- Specified by:
evaluate
in interface Expression
- Overrides:
evaluate
in class DefaultExpression
setExpression
public void setExpression(Expression e)
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