Package org.geotools.filter

Interface FunctionFactory

All Known Implementing Classes:
DefaultFunctionFactory, MBFunctionFactory, 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:

  • Method Details

    • 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.