org.geotools.filter

Interface FunctionFactory

All Known Implementing Classes:

DefaultFunctionFactory, PolygonLabelFunctionFactory, ProcessFunctionFactory

public interface FunctionFactory

Factory interface for filter functions.

The factory provides a list of {#link FunctionName} describing the available functions. Each FunctionName provides details of the name, expected arguments and return type.

Individual functions can be created using a name from this list, along with the required number of arguments and a fallback value.

Prior to GeoTools 2.7 functions were made available as individual factories using FunctionExpression.

Since:

2.7

Author:

Justin Deoliveira (Boundless)

See Also:

Function

Method Summary

Modifier and Type	Method and Description
Function	function(Name name, List<Expression> args, Literal fallback) Returns a function with the specified name.
Function	function(String name, List<Expression> args, Literal fallback) Returns a function with the specified name.
List<FunctionName>	getFunctionNames() Returns the list of function names the factory provides.

Method Detail

getFunctionNames

List<FunctionName> getFunctionNames()

Returns the list of function names the factory provides.

Returns:

A list of function names, possibly empty, never null.

function

Function function(String name,
                  List<Expression> args,
                  Literal fallback)

Returns a function with the specified name.

Parameters:

name - The name of the function

args - Variable list of expression arguments for the function.

fallback - A fallback literal to use in cases where the function does not exist or can not be created. This argument may be null.

function

Function function(Name name,
                  List<Expression> args,
                  Literal fallback)

Returns a function with the specified name.

Parameters:

name - The name of the function

args - Variable list of expression arguments for the function.

fallback - A fallback literal to use in cases where the function does not exist or can not be created. This argument may be null.