Package org.topbraid.jenax.functions

Class CurrentThreadFunctionRegistry

java.lang.Object
org.apache.jena.sparql.function.FunctionRegistry
org.topbraid.jenax.functions.CurrentThreadFunctionRegistry
public class CurrentThreadFunctionRegistry extends org.apache.jena.sparql.function.FunctionRegistry
An ARQ FunctionRegistry that can be used to associate functions with Threads, so that additional functions from a given Model can be made visible depending on the SPARQL query thread.

The contract of this class is very strict to prevent memory leaks: Users always need to make sure that unregister is called as soon as a query (block) ends, and to restore any old CurrentThreadFunctions object that was registered before. So a typical block would be:

Model model = ... a Model with extra SHACL/SPIN functions CurrentThreadFunctions old = CurrentThreadFunctionRegistry.register(model); try { // run SPARQL queries here } finally { CurrentThreadFunctionRegistry.unregister(old); }

In preparation of the above, the application should start up with code such as

FunctionRegistry oldFR = FunctionRegistry.get(); CurrentThreadFunctionRegistry threadFR = new CurrentThreadFunctionRegistry(oldFR); FunctionRegistry.set(ARQ.getContext(), threadFR);

and (for SPIN) do the same for the SPINThreadPropertyFunctionRegistry.

Author:
Holger Knublauch

  • Method Details

    • get

      public static CurrentThreadFunctionRegistry get()

    • register

      public static Runnable register(org.apache.jena.rdf.model.Model model)
      Registers a set of extra SPIN functions from a given Model for the current Thread.
      Parameters:
      model - the Model containing the SPIN functions
      Returns:
      a Runnable that must be called (in a finally block) when done to restore the previous state

    • getFunctions

      public static CurrentThreadFunctions getFunctions()

    • get

      public org.apache.jena.sparql.function.FunctionFactory get(String uri)
      Overrides:
      get in class org.apache.jena.sparql.function.FunctionRegistry

    • isRegistered

      public boolean isRegistered(String uri)
      Overrides:
      isRegistered in class org.apache.jena.sparql.function.FunctionRegistry

    • keys

      public Iterator<String> keys()
      Overrides:
      keys in class org.apache.jena.sparql.function.FunctionRegistry

    • put

      public void put(String uri, Class<?> funcClass)
      Overrides:
      put in class org.apache.jena.sparql.function.FunctionRegistry

    • put

      public void put(String uri, org.apache.jena.sparql.function.FunctionFactory f)
      Overrides:
      put in class org.apache.jena.sparql.function.FunctionRegistry

    • remove

      public org.apache.jena.sparql.function.FunctionFactory remove(String uri)
      Overrides:
      remove in class org.apache.jena.sparql.function.FunctionRegistry