Fixed race condition issue during TurtleLoader.loadTurtle

#411
eclipse-esmf · Oct 11, 2023 · 022f844 · 022f844
1 parent 2599683
commit 022f844
Showing 1 changed file with 14 additions and 1 deletion.
diff --git a/...l-resolver/src/main/java/org/eclipse/esmf/aspectmodel/resolver/services/TurtleLoader.java b/...l-resolver/src/main/java/org/eclipse/esmf/aspectmodel/resolver/services/TurtleLoader.java
@@ -39,6 +39,8 @@
 public final class TurtleLoader {
    private static final Logger LOG = LoggerFactory.getLogger( TurtleLoader.class );
 
+   private static volatile boolean isTurtleRegistered = false;
+
    private TurtleLoader() {
 
    }
@@ -62,7 +64,7 @@ public static Try<Model> loadTurtle( @Nullable final InputStream inputStream ) {
             .collect( Collectors.joining( "\n" ) );
 
       final Model streamModel = ModelFactory.createDefaultModel();
-      RDFParserRegistry.registerLangTriples( Lang.TURTLE, ReaderRIOTTurtle.factory );
+      registerTurtle();
       try ( final InputStream turtleInputStream = new ByteArrayInputStream( modelContent.getBytes( StandardCharsets.UTF_8 ) ) ) {
          streamModel.read( turtleInputStream, "", RDFLanguages.TURTLE.getName() );
          return Try.success( streamModel );
@@ -79,6 +81,17 @@ public static Try<Model> loadTurtle( @Nullable final InputStream inputStream ) {
       }
    }
 
+   private static void registerTurtle() {
+      if( isTurtleRegistered )
+         return;
+      synchronized ( TurtleLoader.class ){
+         if( !isTurtleRegistered ){
+            RDFParserRegistry.registerLangTriples( Lang.TURTLE, ReaderRIOTTurtle.factory );
+            isTurtleRegistered = true;
+         }
+      }
+   }
+
    /**
     * Opens an URL and returns its InputStream, but does not throw a checked exception.
     *