Module org.apache.jena.arq

Package org.apache.jena.sparql.function.library

Class eval

java.lang.Object

org.apache.jena.sparql.function.library.eval

All Implemented Interfaces:

Function

public class eval
extends Object
implements Function

Function that evaluates an expression. To convert errors to true or false, use COALESCE.

Constructor Summary

Constructors

Constructor	Description
eval()

Method Summary

Modifier and Type	Method	Description
void	build(String uri, ExprList args, Context context)	Called during query plan construction immediately after the construction of the extension instance.
NodeValue	exec(Binding binding, ExprList args, String uri, FunctionEnv env)	Processes unevaluated arguments

Methods inherited from class java.lang.Object

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

Constructor Details

eval

public eval()

Method Details

build

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

Description copied from interface: Function

Called during query plan construction immediately after the construction of the extension instance. A function can throw ExprException if something is wrong (like wrong number of arguments).

Specified by:

build in interface Function

Parameters:

uri - The function URI

args - The parsed arguments

context - The build context.

exec

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

Processes unevaluated arguments

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