diff --git a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/util/MainThreadExecutor.java b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/util/MainThreadExecutor.java
deleted file mode 100644
index 12c1ae55..00000000
--- a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/util/MainThreadExecutor.java
+++ /dev/null
@@ -1,26 +0,0 @@
-/*
- * MainThreadExecutor.java
- * Copyright (C) 2009-2022 Ultrasonic developers
- *
- * Distributed under terms of the GNU GPLv3 license.
- */
-
-package org.moire.ultrasonic.util;
-
-import android.os.Handler;
-import android.os.Looper;
-
-import java.util.concurrent.Executor;
-
-/*
-* Executor for running Futures on the main thread
-* See https://stackoverflow.com/questions/52642246/how-to-get-executor-for-main-thread-on-api-level-28
-*/
-public class MainThreadExecutor implements Executor {
-    private final Handler handler = new Handler(Looper.getMainLooper());
-
-    @Override
-    public void execute(Runnable r) {
-        handler.post(r);
-    }
-}
diff --git a/ultrasonic/src/main/kotlin/org/moire/ultrasonic/util/MainThreadExecutor.kt b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/util/MainThreadExecutor.kt
new file mode 100644
index 00000000..afc72563
--- /dev/null
+++ b/ultrasonic/src/main/kotlin/org/moire/ultrasonic/util/MainThreadExecutor.kt
@@ -0,0 +1,22 @@
+/*
+ * MainThreadExecutor.java
+ * Copyright (C) 2009-2022 Ultrasonic developers
+ *
+ * Distributed under terms of the GNU GPLv3 license.
+ */
+package org.moire.ultrasonic.util
+
+import android.os.Handler
+import android.os.Looper
+import java.util.concurrent.Executor
+
+/*
+* Executor for running Futures on the main thread
+* See https://stackoverflow.com/questions/52642246/how-to-get-executor-for-main-thread-on-api-level-28
+*/
+class MainThreadExecutor : Executor {
+    private val handler = Handler(Looper.getMainLooper())
+    override fun execute(r: Runnable) {
+        handler.post(r)
+    }
+}
\ No newline at end of file