httpsgithu
diff --git a/‎objectbox-java/src/main/java/io/objectbox/Box.java‎
Lines changed: 27 additions & 0 deletions b/‎objectbox-java/src/main/java/io/objectbox/Box.java‎
Lines changed: 27 additions & 0 deletions
diff --git a/‎objectbox-java/src/main/java/io/objectbox/Cursor.java‎
Lines changed: 19 additions & 1 deletion b/‎objectbox-java/src/main/java/io/objectbox/Cursor.java‎
Lines changed: 19 additions & 1 deletion
@@ -36,6 +36,7 @@
 import io.objectbox.internal.IdGetter;
 import io.objectbox.internal.ReflectionCache;
 import io.objectbox.query.QueryBuilder;
+import io.objectbox.relation.RelationInfo;
 
 /**
  * A box to store objects of a particular class.
@@ -599,6 +600,32 @@ public List<T> internalGetRelationEntities(int sourceEntityId, int relationId, l
         }
     }
 
+    @Internal
+    public long[] internalGetRelationIds(int sourceEntityId, int relationId, long key, boolean backlink) {
+        Cursor<T> reader = getReader();
+        try {
+            return reader.getRelationIds(sourceEntityId, relationId, key, backlink);
+        } finally {
+            releaseReader(reader);
+        }
+    }
+
+    public List<T> getRelationEntities(RelationInfo relationInfo, long id) {
+        return internalGetRelationEntities(relationInfo.sourceInfo.getEntityId(), relationInfo.relationId, id, false);
+    }
+
+    public List<T> getRelationBacklinkEntities(RelationInfo relationInfo, long id) {
+        return internalGetRelationEntities(relationInfo.targetInfo.getEntityId(), relationInfo.relationId, id, true);
+    }
+
+    public long[] getRelationIds(RelationInfo relationInfo, long id) {
+        return internalGetRelationIds(relationInfo.sourceInfo.getEntityId(), relationInfo.relationId, id, false);
+    }
+
+    public long[] getRelationBacklinkIds(RelationInfo relationInfo, long id) {
+        return internalGetRelationIds(relationInfo.targetInfo.getEntityId(), relationInfo.relationId, id, true);
+    }
+
     @Internal
     public <RESULT> RESULT internalCallWithReaderHandle(CallWithHandle<RESULT> task) {
         Cursor<T> reader = getReader();
 
@@ -24,7 +24,6 @@
 
 import io.objectbox.annotation.apihint.Beta;
 import io.objectbox.annotation.apihint.Internal;
-import io.objectbox.annotation.apihint.Temporary;
 import io.objectbox.relation.ToMany;
 
 @SuppressWarnings({"unchecked", "SameParameterValue", "unused", "WeakerAccess", "UnusedReturnValue"})
@@ -113,8 +112,12 @@ protected static native long collect004000(long cursor, long keyIfComplete, int
 
     static native List nativeGetBacklinkEntities(long cursor, int entityId, int propertyId, long key);
 
+    static native long[] nativeGetBacklinkIds(long cursor, int entityId, int propertyId, long key);
+
     static native List nativeGetRelationEntities(long cursor, int sourceEntityId, int relationId, long key, boolean backlink);
 
+    static native long[] nativeGetRelationIds(long cursor, int sourceEntityId, int relationId, long key, boolean backlink);
+
     static native void nativeModifyRelations(long cursor, int relationId, long key, long[] targetKeys, boolean remove);
 
     static native void nativeModifyRelationsSingle(long cursor, int relationId, long key, long targetKey, boolean remove);
@@ -281,11 +284,26 @@ List<T> getBacklinkEntities(int entityId, Property relationIdProperty, long key)
         }
     }
 
+    @Internal
+    long[] getBacklinkIds(int entityId, Property relationIdProperty, long key) {
+        try {
+            return nativeGetBacklinkIds(cursor, entityId, relationIdProperty.getId(), key);
+        } catch (IllegalArgumentException e) {
+            throw new IllegalArgumentException("Please check if the given property belongs to a valid @Relation: "
+                    + relationIdProperty, e);
+        }
+    }
+
     @Internal
     public List<T> getRelationEntities(int sourceEntityId, int relationId, long key, boolean backlink) {
         return nativeGetRelationEntities(cursor, sourceEntityId, relationId, key, backlink);
     }
 
+    @Internal
+    public long[] getRelationIds(int sourceEntityId, int relationId, long key, boolean backlink) {
+        return nativeGetRelationIds(cursor, sourceEntityId, relationId, key, backlink);
+    }
+
     @Internal
     public void modifyRelations(int relationId, long key, long[] targetKeys, boolean remove) {
         nativeModifyRelations(cursor, relationId, key, targetKeys, remove);