org.geotools.filter.function
Class PropertyExistsFunction
Object
ExpressionAbstract
DefaultExpression
FunctionExpressionImpl
PropertyExistsFunction
- All Implemented Interfaces:
- Factory, ExpressionType, FunctionExpression, Expression, Function
public class PropertyExistsFunction
- extends FunctionExpressionImpl
A new function to check if a property exists.
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 |
Method Summary |
boolean |
equals(Object obj)
|
Object |
evaluate(Object bean)
This method checks if the object is an instance of Feature and
if so, calls through to #evaluate(Feature) . |
Object |
evaluate(SimpleFeature feature)
Returns a value for this expression. |
int |
getArgCount()
Gets the number of arguments that are set. |
String |
toString()
Creates a String representation of this Function with
the function name and the arguments. |
Methods inherited from class FunctionExpressionImpl |
accept, getArgs, getExpression, getFallbackValue, getImplementationHints, getName, getParameters, getType, setArgs, setFallbackValue, setName, setParameters |
Methods inherited from interface Expression |
evaluate |
Methods inherited from interface Expression |
evaluate |
PropertyExistsFunction
public PropertyExistsFunction()
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.
evaluate
public Object evaluate(SimpleFeature feature)
- Description copied from class:
DefaultExpression
- Returns a value for this expression. If the expression is an attribute
expression then the attribute of the feature should be returned. If a
literal then the feature is ignored, the literal is returned as it has
no relation to the feature.
- Overrides:
evaluate
in class DefaultExpression
- Parameters:
feature
- Specified feature to use when returning value.
- Returns:
Boolean.TRUE
if the feature
's
FeatureType
contains an attribute named as the property
name passed as this function argument, Boolean.FALSE
otherwise.
evaluate
public Object evaluate(Object bean)
- 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
- Returns:
Boolean.TRUE
if the Class of the object passed as
argument defines a property names as the property name passed as
this function argument, following the standard Java Beans naming
conventions for getters. Boolean.FALSE
otherwise.
toString
public String toString()
- Description copied from class:
FunctionExpressionImpl
- Creates a String representation of this Function with
the function name and the arguments. The String created
should be good for most subclasses
- Overrides:
toString
in class FunctionExpressionImpl
equals
public boolean equals(Object obj)
- Overrides:
equals
in class FunctionExpressionImpl
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