Module org.apache.jena.arq

Package org.apache.jena.sparql.function.user

Class UserDefinedFunction

java.lang.Object

org.apache.jena.sparql.function.user.UserDefinedFunctionDefinition

org.apache.jena.sparql.function.user.UserDefinedFunction

All Implemented Interfaces:

Function

public class UserDefinedFunction
extends UserDefinedFunctionDefinition
implements Function

Represents a user defined function

Field Summary

Fields inherited from class org.apache.jena.sparql.function.user.UserDefinedFunctionDefinition

warnOnUnusedVariable

Constructor Summary

Constructors

Constructor	Description
UserDefinedFunction(String url, Expr e, List<Var> argList)	Creates a user defined function
UserDefinedFunction(UserDefinedFunctionDefinition def)	Creates a new user defined function

Method Summary

Modifier and Type	Method	Description
void	build(String uri, ExprList args)	Builds the expression substituting the arguments given into the base expression to yield the actual expression to evaluate
void	build(String uri, ExprList args, Context context)	Builds the expression substituting the arguments given into the base expression to yield the actual expression to evaluate
NodeValue	exec(Binding binding, ExprList args, String uri, FunctionEnv env)	Executes the function
Expr	getActualExpr()	Gets the actual expression that was built for the function, assuming build(String, ExprList, Context) has been called

Methods inherited from class org.apache.jena.sparql.function.user.UserDefinedFunctionDefinition

getArgList, getBaseExpr, getUri, newFunctionInstance

Methods inherited from class java.lang.Object

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

Constructor Details

UserDefinedFunction

public UserDefinedFunction(UserDefinedFunctionDefinition def)

Creates a new user defined function

Parameters:

def - Function Definition

UserDefinedFunction

public UserDefinedFunction(String url,
 Expr e,
 List<Var> argList)

Creates a user defined function

Parameters:

url - Function URL

e - Expression

argList - Arguments

Method Details

build

public void build(String uri,
 ExprList args)

Builds the expression substituting the arguments given into the base expression to yield the actual expression to evaluate

Throws:

SSE_ExprBuildException - Thrown if an expression cannot be generated

build

public void build(String uri,
 ExprList args,
 Context context)

Builds the expression substituting the arguments given into the base expression to yield the actual expression to evaluate

Specified by:

build in interface Function

Parameters:

uri - The function URI

args - The parsed arguments

context - The build context.

Throws:

SSE_ExprBuildException - Thrown if an expression cannot be generated

exec

public NodeValue exec(Binding binding,
 ExprList args,
 String uri,
 FunctionEnv env)

Executes the function

Specified by:

exec in interface Function

Parameters:

binding - The current solution

args - A list of unevaluated expressions

uri - The name of this

env - The execution context

Returns:

NodeValue - a value

getActualExpr

public Expr getActualExpr()

Gets the actual expression that was built for the function, assuming build(String, ExprList, Context) has been called

Returns:

Expression if built, null otherwise