| /* |
| * Licensed to the Apache Software Foundation (ASF) under one |
| * or more contributor license agreements. See the NOTICE file |
| * distributed with this work for additional information |
| * regarding copyright ownership. The ASF licenses this file |
| * to you under the Apache License, Version 2.0 (the |
| * "License"); you may not use this file except in compliance |
| * with the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| package org.apache.jena.sparql.function; |
| import java.util.HashMap ; |
| import java.util.HashSet ; |
| import java.util.Iterator ; |
| import java.util.Map ; |
| import java.util.Set ; |
| |
| import org.apache.jena.atlas.logging.Log ; |
| import org.apache.jena.query.ARQ ; |
| import org.apache.jena.sparql.ARQConstants ; |
| import org.apache.jena.sparql.util.Context ; |
| import org.apache.jena.sparql.util.MappedLoader ; |
| |
| public class FunctionRegistry //extends HashMap<String, Function> |
| { |
| // Extract a Registry class and do casting and initialization here. |
| Map<String, FunctionFactory> registry = new HashMap<>() ; |
| Set<String> attemptedLoads = new HashSet<>() ; |
| |
| public static FunctionRegistry standardRegistry() |
| { |
| FunctionRegistry reg = get(ARQ.getContext()) ; |
| return reg ; |
| } |
| |
| public static void init() { |
| // Initialize if there is no registry already set |
| FunctionRegistry reg = new FunctionRegistry() ; |
| ARQFunctions.load(reg); |
| StandardFunctions.loadStdDefs(reg) ; |
| set(ARQ.getContext(), reg) ; |
| } |
| |
| public static FunctionRegistry get() |
| { |
| // Initialize if there is no registry already set |
| FunctionRegistry reg = get(ARQ.getContext()) ; |
| if ( reg == null ) |
| { |
| Log.warn(FunctionRegistry.class, "Standard function registry should already have been initialized"); |
| init() ; |
| reg = get(ARQ.getContext()) ; |
| } |
| |
| return reg ; |
| } |
| |
| public static FunctionRegistry get(Context context) |
| { |
| if ( context == null ) |
| return null ; |
| return (FunctionRegistry)context.get(ARQConstants.registryFunctions) ; |
| } |
| |
| public static void set(Context context, FunctionRegistry reg) |
| { |
| context.set(ARQConstants.registryFunctions, reg) ; |
| } |
| |
| public FunctionRegistry() |
| {} |
| |
| /** Insert a class that is the function implementation |
| * |
| * @param uri String URI |
| * @param funcClass Class for the function (new instance called). |
| */ |
| public void put(String uri, Class<?> funcClass) |
| { |
| if ( ! Function.class.isAssignableFrom(funcClass) ) |
| { |
| Log.warn(this, "Class "+funcClass.getName()+" is not a Function" ); |
| return ; |
| } |
| |
| put(uri, new FunctionFactoryAuto(funcClass)) ; |
| } |
| |
| /** Insert a function. Re-inserting with the same URI overwrites the old entry. |
| * |
| * @param uri |
| * @param f |
| */ |
| public void put(String uri, FunctionFactory f) { registry.put(uri,f) ; } |
| |
| /** Lookup by URI */ |
| public FunctionFactory get(String uri) |
| { |
| FunctionFactory function = registry.get(uri) ; |
| if ( function != null ) |
| return function ; |
| |
| if ( attemptedLoads.contains(uri) ) |
| return null ; |
| |
| Class<?> functionClass = MappedLoader.loadClass(uri, Function.class) ; |
| if ( functionClass == null ) |
| return null ; |
| // Registry it |
| put(uri, functionClass) ; |
| attemptedLoads.add(uri) ; |
| // Call again to get it. |
| return registry.get(uri) ; |
| } |
| |
| public boolean isRegistered(String uri) { return registry.containsKey(uri) ; } |
| |
| /** Remove by URI */ |
| public FunctionFactory remove(String uri) { return registry.remove(uri) ; } |
| |
| /** Iterate over URIs */ |
| public Iterator<String> keys() { return registry.keySet().iterator() ; } |
| |
| } |