Android Java throw exception if cannot load model or tokenizer

Author: kirklandsign

extension/android/executorch_android/src/main/java/org/pytorch/executorch/Module.java

@@ -11,6 +11,8 @@
 import android.util.Log;
 import com.facebook.soloader.nativeloader.NativeLoader;
 import com.facebook.soloader.nativeloader.SystemDelegate;
+import java.nio.file.Files;
+import java.nio.file.Paths;
 import java.util.concurrent.locks.Lock;
 import java.util.concurrent.locks.ReentrantLock;
 import org.pytorch.executorch.annotations.Experimental;
@@ -52,6 +54,9 @@ public static Module load(final String modelPath, int loadMode) {
     if (!NativeLoader.isInitialized()) {
       NativeLoader.init(new SystemDelegate());
     }
+    if (!Files.isReadable(Paths.get(modelPath))) {
+      throw new RuntimeException("Cannot load model path " + modelPath);
+    }
     return new Module(new NativePeer(modelPath, loadMode));
   }
 

extension/android/executorch_android/src/main/java/org/pytorch/executorch/extension/llm/LlmModule.java

@@ -12,6 +12,8 @@
 import com.facebook.jni.annotations.DoNotStrip;
 import com.facebook.soloader.nativeloader.NativeLoader;
 import com.facebook.soloader.nativeloader.SystemDelegate;
+import java.nio.file.Files;
+import java.nio.file.Paths;
 import org.pytorch.executorch.annotations.Experimental;
 
 /**
@@ -41,33 +43,47 @@ public class LlmModule {
   private static native HybridData initHybrid(
       int modelType, String modulePath, String tokenizerPath, float temperature, String dataPath);
 
+  /**
+   * Constructs a LLM Module for a model with given type, model path, tokenizer, temperature, and
+   * data path.
+   */
+  public LlmModule(
+      int modelType, String modulePath, String tokenizerPath, float temperature, String dataPath) {
+    if (!Files.isReadable(Paths.get(modulePath))) {
+      throw new RuntimeException("Cannot load model path " + modulePath);
+    }
+    if (!Files.isReadable(Paths.get(tokenizerPath))) {
+      throw new RuntimeException("Cannot load tokenizer path " + tokenizerPath);
+    }
+    mHybridData = initHybrid(modelType, modulePath, tokenizerPath, temperature, dataPath);
+  }
+
   /** Constructs a LLM Module for a model with given model path, tokenizer, temperature. */
   public LlmModule(String modulePath, String tokenizerPath, float temperature) {
-    mHybridData = initHybrid(MODEL_TYPE_TEXT, modulePath, tokenizerPath, temperature, null);
+    this(MODEL_TYPE_TEXT, modulePath, tokenizerPath, temperature, null);
   }
 
   /**
    * Constructs a LLM Module for a model with given model path, tokenizer, temperature and data
    * path.
    */
   public LlmModule(String modulePath, String tokenizerPath, float temperature, String dataPath) {
-    mHybridData = initHybrid(MODEL_TYPE_TEXT, modulePath, tokenizerPath, temperature, dataPath);
+    this(MODEL_TYPE_TEXT, modulePath, tokenizerPath, temperature, dataPath);
   }
 
   /** Constructs a LLM Module for a model with given path, tokenizer, and temperature. */
   public LlmModule(int modelType, String modulePath, String tokenizerPath, float temperature) {
-    mHybridData = initHybrid(modelType, modulePath, tokenizerPath, temperature, null);
+    this(modelType, modulePath, tokenizerPath, temperature, null);
   }
 
   /** Constructs a LLM Module for a model with the given LlmModuleConfig */
   public LlmModule(LlmModuleConfig config) {
-    mHybridData =
-        initHybrid(
-            config.getModelType(),
-            config.getModulePath(),
-            config.getTokenizerPath(),
-            config.getTemperature(),
-            config.getDataPath());
+    this(
+        config.getModelType(),
+        config.getModulePath(),
+        config.getTokenizerPath(),
+        config.getTemperature(),
+        config.getDataPath());
   }
 
   public void resetNative() {