Restructure Kotlin APIs to Share Common Code in core/

.github/workflows/ci-build.yml

@@ -164,7 +164,7 @@ jobs:
             @litert//litert/vendors/qualcomm/dispatch:dispatch_api_so \
             -- \
             -//python/... \
-            -//kotlin/java/com/google/ai/edge/litertlm/example/...
+            -//kotlin/kotlin/com/google/ai/edge/litertlm/example/...
         env:
           ANDROID_NDK_HOME: ${{ steps.setup-ndk.outputs.ndk-path }}
 

.github/workflows/ml-ci-build-android.yml

@@ -225,7 +225,7 @@ jobs:
             @litert//litert/vendors/qualcomm/dispatch:dispatch_api_so \
             -- \
             -//python/... \
-            -//kotlin/java/com/google/ai/edge/litertlm/example/... \
+            -//kotlin/kotlin/com/google/ai/edge/litertlm/example/... \
             -//runtime/components/rust/...
 
       - name: Update litert_lm_main prebuilt for Android if new version tag is pushed.

agents/skills/create-litert-lm-android-demo-app/references/dependency_source_build.md

@@ -28,7 +28,7 @@ integrate them. Agents MUST follow these steps when the user chooses the
     `--config=android_x86` for `x86`, or `--config=android_x86_64` for
     `x86_64`):
     *   **Kotlin Class JAR**: Compile the Kotlin bindings (e.g.,
-        `//kotlin/java/com/google/ai/edge/litertlm:litertlm-android`). Locate
+        `//kotlin/kotlin/com/google/ai/edge/litertlm:litertlm-android`). Locate
         the resulting output `.jar` that contains the compiled `.class` files.
     *   **Native JNI JAR**: Compile the native JNI libraries. Zip all required
         `.so` files into a directory structure `lib/<target_abi>/` inside a
@@ -65,7 +65,7 @@ prebuilt targets.
 **Discovered Dependency Exports**: When configuring the `litertlm_kotlin`
 target, you MUST inspect the original `BUILD` file of the bindings library
 inside your cloned LiteRT-LM source tree (e.g. read the `deps` attribute of the
-`//kotlin/java/com/google/ai/edge/litertlm:litertlm-android` build target).
+`//kotlin/kotlin/com/google/ai/edge/litertlm:litertlm-android` build target).
 Register all third-party external libraries listed there inside the `exports`
 attribute of the prebuilt `java_import`. This transitively propagates compiling
 and runtime classpaths to the sample app, maintaining clean modular

docs/api/kotlin/getting_started.md

@@ -31,10 +31,10 @@ suspend fun main() {
 ![](demo.gif)
 
 To try out the above sample, clone the repo and run with
-[example/Main.kt](../../../kotlin/java/com/google/ai/edge/litertlm/example/Main.kt):
+[example/Main.kt](../../../kotlin/kotlin/com/google/ai/edge/litertlm/example/Main.kt):
 
 ```bazel
-bazel run -c opt //kotlin/java/com/google/ai/edge/litertlm/example:main -- <abs_model_path>
+bazel run -c opt //kotlin/kotlin/com/google/ai/edge/litertlm/example:main -- <abs_model_path>
 ```
 
 Available `.litertlm` models are on the
@@ -52,18 +52,46 @@ Gradle/Maven users.
 
 ### 1. Add the Gradle dependency
 
+#### Standard
+
 ```
 dependencies {
-    // For Android
+    // For Android source set
     implementation("com.google.ai.edge.litertlm:litertlm-android:latest.release")
 
-    // For JVM (Linux, MacOS, Windows)
+    // OR
+
+    // For JVM (Linux, macOS, Windows) source set
     implementation("com.google.ai.edge.litertlm:litertlm-jvm:latest.release")
 }
 ```
 
+#### Multiplatform
+
+```
+commonMain {
+    dependencies {
+        // For common source set
+        implementation("com.google.ai.edge.litertlm:litertlm-core:latest.release")
+    }
+}
+androidMain {
+    dependencies {
+        // For Android source set
+        implementation("com.google.ai.edge.litertlm:litertlm-android:latest.release")
+    }
+}
+jvmMain {
+    dependencies {
+        // For JVM (Linux, macOS, Windows) source set
+        implementation("com.google.ai.edge.litertlm:litertlm-jvm:latest.release")
+    }
+}
+```
+
 You can find the available versions on Google Maven in
-[litertlm-android](https://maven.google.com/web/index.html#com.google.ai.edge.litertlm:litertlm-android)
+[litertlm-core](https://maven.google.com/web/index.html#com.google.ai.edge.litertlm:litertlm-core),
+[litertlm-android](https://maven.google.com/web/index.html#com.google.ai.edge.litertlm:litertlm-android),
 and
 [litertlm-jvm](https://maven.google.com/web/index.html#com.google.ai.edge.litertlm:litertlm-jvm).
 
@@ -194,8 +222,6 @@ through a callback.
 import com.google.ai.edge.litertlm.Content
 import com.google.ai.edge.litertlm.Message
 import com.google.ai.edge.litertlm.MessageCallback
-import java.util.concurrent.CountDownLatch
-import java.util.concurrent.TimeUnit
 
 val callback = object : MessageCallback {
     override fun onMessage(message: Message) {
@@ -450,10 +476,10 @@ if (responseMessage.toolCalls.isNotEmpty()) {
 #### Example
 
 To try out tool use, clone the repo and run with
-[example/ToolMain.kt](../../../kotlin/java/com/google/ai/edge/litertlm/example/ToolMain.kt):
+[example/ToolMain.kt](../../../kotlin/kotlin/com/google/ai/edge/litertlm/example/ToolMain.kt):
 
 ```bazel
-bazel run -c opt //kotlin/java/com/google/ai/edge/litertlm/example:tool -- <abs_model_path>
+bazel run -c opt //kotlin/kotlin/com/google/ai/edge/litertlm/example:tool -- <abs_model_path>
 ```
 
 ### 7. Extra Template Context Variables
@@ -485,7 +511,7 @@ These variables are used within the Jinja-style prompt templates, e.g.,
 
 ## Error Handling
 
-API methods can throw `LiteRtLmJniException` for errors from the native layer or
+API methods can throw `LiteRtLmNativeException` for errors from the native layer or
 standard Kotlin exceptions like `IllegalStateException` for lifecycle issues.
 Always wrap API calls in try-catch blocks. The `onError` callback in
 `MessageCallback` will also report errors during asynchronous operations.

kotlin/java/com/google/ai/edge/litertlm/BUILD → kotlin/kotlin/com/google/ai/edge/litertlm/android/BUILD

@@ -13,26 +13,16 @@
 # limitations under the License.
 
 load("@rules_kotlin//kotlin:android.bzl", "kt_android_library")
-load("@rules_kotlin//kotlin:jvm.bzl", "kt_jvm_library")
 
 package(default_visibility = ["//visibility:public"])
 
-kt_jvm_library(
-    name = "litertlm-jvm",
-    srcs = glob(["*.kt"]),
-    resources = ["//kotlin/java/com/google/ai/edge/litertlm/jni:litertlm_jni"],
-    resource_strip_prefix = "kotlin/java",
-    deps = [
-        "@rules_kotlin//kotlin/compiler:kotlin-reflect",
-        "@maven//:com_google_code_gson_gson",
-        "@maven//:org_jetbrains_kotlinx_kotlinx_coroutines_core_jvm"
-    ],
-)
-
-# Note: To build with dynamic linking, use the following build flags:
 kt_android_library(
     name = "litertlm-android",
     srcs = glob(["*.kt"]),
+    associates = [
+        "//kotlin/kotlin/com/google/ai/edge/litertlm/core:litertlm-core",
+        "//kotlin/kotlin/com/google/ai/edge/litertlm/jni:litertlm-jni",
+    ],
     deps = [
         "@rules_kotlin//kotlin/compiler:kotlin-reflect",
         "@maven//:com_google_code_gson_gson",

kotlin/kotlin/com/google/ai/edge/litertlm/android/Engine.kt

@@ -0,0 +1,37 @@
+/*
+ * Copyright 2025 Google LLC
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package com.google.ai.edge.litertlm
+
+import com.google.gson.JsonArray
+
+/**
+ * Manages the lifecycle of a LiteRT-LM engine, providing an interface for interacting with the
+ * underlying native library.
+ *
+ * Example usage:
+ * ```
+ * val config = EngineConfig(modelPath = "...")
+ * val engine = Engine(config)
+ * engine.initialize()
+ * ...
+ * engine.close()
+ * ```
+ *
+ * @param engineConfig The configuration for the engine.
+ */
+fun Engine(engineConfig: EngineConfig): Engine {
+    return EngineJni(engineConfig, NativeLibraryLoaderJni)
+}

kotlin/kotlin/com/google/ai/edge/litertlm/core/BUILD

@@ -0,0 +1,27 @@
+# Copyright 2025 Google LLC
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+load("@rules_kotlin//kotlin:jvm.bzl", "kt_jvm_library")
+
+package(default_visibility = ["//visibility:public"])
+
+kt_jvm_library(
+    name = "litertlm-core",
+    srcs = glob(["*.kt"]),
+    deps = [
+        "@rules_kotlin//kotlin/compiler:kotlin-reflect",
+        "@maven//:com_google_code_gson_gson",
+        "@maven//:org_jetbrains_kotlinx_kotlinx_coroutines_core_jvm"
+    ],
+)

kotlin/java/com/google/ai/edge/litertlm/Benchmark.kt → kotlin/kotlin/com/google/ai/edge/litertlm/core/Benchmark.kt

@@ -66,7 +66,7 @@ fun benchmark(
   prompt: String = "How are you",
 ): BenchmarkInfo {
   val enginePointer =
-    LiteRtLmJni.nativeCreateBenchmark(
+    LiteRtLmNative.nativeCreateBenchmark(
       modelPath,
       backend.name,
       prefillTokens,
@@ -78,7 +78,7 @@ fun benchmark(
 
   try {
     val conversationHandle =
-      LiteRtLmJni.nativeCreateConversation(
+      LiteRtLmNative.nativeCreateConversation(
         enginePointer,
         null, // SamplerConfig
         "[]", // messagesJsonString
@@ -97,6 +97,6 @@ fun benchmark(
       return conversation.getBenchmarkInfo()
     }
   } finally {
-    LiteRtLmJni.nativeDeleteEngine(enginePointer)
+    LiteRtLmNative.nativeDeleteEngine(enginePointer)
   }
 }

kotlin/java/com/google/ai/edge/litertlm/Capabilities.kt → kotlin/kotlin/com/google/ai/edge/litertlm/core/Capabilities.kt

@@ -15,7 +15,7 @@
  */
 package com.google.ai.edge.litertlm
 
-import kotlin.jvm.Volatile
+import kotlin.concurrent.Volatile
 
 /**
  * Provides information about capabilities and features supported by a LiteRT-LM file.
@@ -31,9 +31,9 @@ class Capabilities(modelPath: String) : AutoCloseable {
   @Volatile private var handle: Long? = null
 
   init {
-    val ptr = LiteRtLmJni.nativeCreateCapabilities(modelPath)
+    val ptr = LiteRtLmNative.nativeCreateCapabilities(modelPath)
     if (ptr == 0L) {
-      throw LiteRtLmJniException("Failed to load capabilities for model: $modelPath")
+      throw LiteRtLmNativeException("Failed to load capabilities for model: $modelPath")
     }
     handle = ptr
   }
@@ -42,15 +42,15 @@ class Capabilities(modelPath: String) : AutoCloseable {
   fun hasSpeculativeDecodingSupport(): Boolean {
     synchronized(lock) {
       checkInitialized()
-      return LiteRtLmJni.nativeHasSpeculativeDecodingSupport(handle!!)
+      return LiteRtLmNative.nativeHasSpeculativeDecodingSupport(handle!!)
     }
   }
 
   /** Closes the loaded capabilities and releases underlying resources. */
   override fun close() {
     synchronized(lock) {
       checkInitialized()
-      LiteRtLmJni.nativeDeleteCapabilities(handle!!)
+      LiteRtLmNative.nativeDeleteCapabilities(handle!!)
       handle = null
     }
   }