Clean up code and allow osgi to set servlet listeners

Author: apottere

src/main/java/graphql/servlet/GraphQLServlet.java

@@ -361,12 +361,6 @@ private <T> void runCallbacks(List<T> callbacks, Consumer<T> action) {
         });
     }
 
-    /**
-     * Don't let listener errors escape to the client.
-     */
-    private <T, R> void runListener(T listener, Function<? super T, ? super R> action) {
-    }
-
     protected static class VariablesDeserializer extends JsonDeserializer<Map<String, Object>> {
         @Override
         public Map<String, Object> deserialize(JsonParser p, DeserializationContext ctxt) throws IOException {

src/main/java/graphql/servlet/OsgiGraphQLServlet.java

@@ -14,9 +14,7 @@
  */
 package graphql.servlet;
 
-import graphql.execution.ExecutionStrategy;
 import graphql.execution.instrumentation.Instrumentation;
-import graphql.schema.GraphQLFieldDefinition;
 import graphql.schema.GraphQLObjectType;
 import graphql.schema.GraphQLSchema;
 import graphql.schema.GraphQLType;
@@ -103,13 +101,13 @@ public void bindProvider(GraphQLProvider provider) {
     }
     public void unbindProvider(GraphQLProvider provider) {
         if (provider instanceof GraphQLQueryProvider) {
-            queryProviders.remove((GraphQLQueryProvider) provider);
+            queryProviders.remove(provider);
         }
         if (provider instanceof GraphQLMutationProvider) {
-            mutationProviders.remove((GraphQLMutationProvider) provider);
+            mutationProviders.remove(provider);
         }
         if (provider instanceof GraphQLTypesProvider) {
-            typesProviders.remove((GraphQLTypesProvider) provider);
+            typesProviders.remove(provider);
         }
         updateSchema();
     }
@@ -144,6 +142,14 @@ public void unbindTypesProvider(GraphQLTypesProvider typesProvider) {
         updateSchema();
     }
 
+    @Reference(cardinality = ReferenceCardinality.MULTIPLE, policyOption = ReferencePolicyOption.GREEDY)
+    public void bindServletListener(GraphQLServletListener listener) {
+        this.addListener(listener);
+    }
+    public void unbindServletListener(GraphQLServletListener listener) {
+        this.removeListener(listener);
+    }
+
     @Reference(cardinality = ReferenceCardinality.OPTIONAL, policyOption = ReferencePolicyOption.GREEDY)
     public void setContextProvider(GraphQLContextBuilder contextBuilder) {
         this.contextBuilder = contextBuilder;