diff --git a/java/src/main/java/org/softwareheritage/graph/SwhBidirectionalGraph.java b/java/src/main/java/org/softwareheritage/graph/SwhBidirectionalGraph.java
--- a/java/src/main/java/org/softwareheritage/graph/SwhBidirectionalGraph.java
+++ b/java/src/main/java/org/softwareheritage/graph/SwhBidirectionalGraph.java
@@ -82,7 +82,7 @@
     public static SwhBidirectionalGraph loadLabelled(LoadMethod method, String path, InputStream is, ProgressLogger pl)
             throws IOException {
         SwhUnidirectionalGraph forward = SwhUnidirectionalGraph.loadLabelledGraphOnly(method, path, is, pl);
-        SwhUnidirectionalGraph backward = SwhUnidirectionalGraph.loadLabelledGraphOnly(method, path + "-transposed", is,
+        SwhUnidirectionalGraph backward = SwhUnidirectionalGraph.loadGraphOnly(method, path + "-transposed", is,
                 pl);
         SwhGraphProperties properties = SwhGraphProperties.load(path);
         forward.setProperties(properties);
diff --git a/java/src/main/java/org/softwareheritage/graph/SwhUnidirectionalGraph.java b/java/src/main/java/org/softwareheritage/graph/SwhUnidirectionalGraph.java
--- a/java/src/main/java/org/softwareheritage/graph/SwhUnidirectionalGraph.java
+++ b/java/src/main/java/org/softwareheritage/graph/SwhUnidirectionalGraph.java
@@ -210,4 +210,8 @@
     public SwhGraphProperties getProperties() {
         return properties;
     }
+
+    public ArcLabelledImmutableGraph getLabelledGraph() {
+        return labelledGraph;
+    }
 }