1 files changed, 27 insertions, 0 deletions
diff --git a/third_party/rust/uniffi_bindgen/src/bindings/kotlin/templates/HandleMap.kt b/third_party/rust/uniffi_bindgen/src/bindings/kotlin/templates/HandleMap.kt
new file mode 100644
index 0000000000..3a56648190
--- /dev/null
+++ b/third_party/rust/uniffi_bindgen/src/bindings/kotlin/templates/HandleMap.kt
@@ -0,0 +1,27 @@
+// Map handles to objects
+//
+// This is used pass an opaque 64-bit handle representing a foreign object to the Rust code.
+internal class UniffiHandleMap<T: Any> {
+    private val map = ConcurrentHashMap<Long, T>()
+    private val counter = java.util.concurrent.atomic.AtomicLong(0)
+
+    val size: Int
+        get() = map.size
+
+    // Insert a new object into the handle map and get a handle for it
+    fun insert(obj: T): Long {
+        val handle = counter.getAndAdd(1)
+        map.put(handle, obj)
+        return handle
+    }
+
+    // Get an object from the handle map
+    fun get(handle: Long): T {
+        return map.get(handle) ?: throw InternalException("UniffiHandleMap.get: Invalid handle")
+    }
+
+    // Remove an entry from the handlemap and get the Kotlin object back
+    fun remove(handle: Long): T {
+        return map.remove(handle) ?: throw InternalException("UniffiHandleMap: Invalid handle")
+    }
+}