Workaround #179, allow load shared library from different ClassLoader

Change-Id: I60ba3469cc841c2bdb2d1696f2b0926c11db1f37

pytorch/pytorch-engine/src/main/java/ai/djl/pytorch/jni/LibUtils.java

@@ -17,6 +17,7 @@
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
+import java.lang.reflect.Method;
 import java.net.URL;
 import java.nio.file.Files;
 import java.nio.file.Path;
@@ -71,7 +72,7 @@ public static void loadLibrary() {
         if (System.getProperty("os.name").startsWith("Win")) {
             loadWinDependencies(libName);
         }
-        System.load(libName); // NOPMD
+        loadNativeLibrary(libName);
     }
 
     public static String getLibName() {
@@ -107,14 +108,14 @@ private static void loadWinDependencies(String libName) {
                             })
                     .map(path -> path.toAbsolutePath().toString())
                     .forEach(System::load);
-            System.load(libDir.resolve("fbgemm.dll").toAbsolutePath().toString());
-            System.load(libDir.resolve("torch_cpu.dll").toAbsolutePath().toString());
+            loadNativeLibrary(libDir.resolve("fbgemm.dll").toAbsolutePath().toString());
+            loadNativeLibrary(libDir.resolve("torch_cpu.dll").toAbsolutePath().toString());
             if (Files.exists(libDir.resolve("c10_cuda.dll"))) {
                 // Windows System.load is global load
-                System.load(libDir.resolve("c10_cuda.dll").toAbsolutePath().toString());
-                System.load(libDir.resolve("torch_cuda.dll").toAbsolutePath().toString());
+                loadNativeLibrary(libDir.resolve("c10_cuda.dll").toAbsolutePath().toString());
+                loadNativeLibrary(libDir.resolve("torch_cuda.dll").toAbsolutePath().toString());
             }
-            System.load(libDir.resolve("torch.dll").toAbsolutePath().toString());
+            loadNativeLibrary(libDir.resolve("torch.dll").toAbsolutePath().toString());
         } catch (IOException e) {
             throw new IllegalArgumentException("Folder not exist! " + libDir, e);
         }
@@ -291,6 +292,20 @@ private static String copyNativeLibraryFromClasspath(Platform platform) {
         }
     }
 
+    private static void loadNativeLibrary(String path) {
+        String nativeHelper = System.getProperty("ai.djl.pytorch.native_helper");
+        if (nativeHelper != null && !nativeHelper.isEmpty()) {
+            try {
+                Class<?> clazz = Class.forName(nativeHelper);
+                Method method = clazz.getDeclaredMethod("load", String.class);
+                method.invoke(null, path);
+            } catch (ReflectiveOperationException e) {
+                throw new IllegalArgumentException("Invalid native_helper: " + nativeHelper, e);
+            }
+        }
+        System.load(path); // NOPMD
+    }
+
     private static String downloadPyTorch(Platform platform, AtomicBoolean fallback)
             throws IOException {
         String version = platform.getVersion();

pytorch/pytorch-engine/src/test/java/ai/djl/pytorch/integration/LibUtilsTest.java

@@ -0,0 +1,41 @@
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"). You may not use this file except in compliance
+ * with the License. A copy of the License is located at
+ *
+ * http://aws.amazon.com/apache2.0/
+ *
+ * or in the "license" file accompanying this file. This file 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 ai.djl.pytorch.integration;
+
+import ai.djl.engine.Engine;
+import org.testng.annotations.AfterClass;
+import org.testng.annotations.BeforeClass;
+import org.testng.annotations.Test;
+
+public class LibUtilsTest {
+
+    @BeforeClass
+    public void setup() {
+        System.setProperty(
+                "ai.djl.pytorch.native_helper", "ai.djl.pytorch.integration.LibUtilsTest");
+    }
+
+    @AfterClass
+    public void teardown() {
+        System.setProperty("ai.djl.pytorch.native_helper", "");
+    }
+
+    @Test
+    public void test() {
+        Engine.getInstance();
+    }
+
+    public static void load(String path) {
+        System.load(path); // NOPMD
+    }
+}

pytorch/pytorch-engine/src/test/java/integration/MkldnnTest.java → pytorch/pytorch-engine/src/test/java/ai/djl/pytorch/integration/MkldnnTest.java

@@ -11,7 +11,7 @@
  * and limitations under the License.
  */
 
-package integration;
+package ai.djl.pytorch.integration;
 
 import ai.djl.ndarray.NDArray;
 import ai.djl.ndarray.NDManager;

pytorch/pytorch-engine/src/test/java/integration/ProfilerTest.java → pytorch/pytorch-engine/src/test/java/ai/djl/pytorch/integration/ProfilerTest.java

@@ -11,7 +11,7 @@
  * and limitations under the License.
  */
 
-package integration;
+package ai.djl.pytorch.integration;
 
 import ai.djl.Application;
 import ai.djl.MalformedModelException;

pytorch/pytorch-engine/src/test/java/integration/package-info.java → pytorch/pytorch-engine/src/test/java/ai/djl/pytorch/integration/package-info.java

@@ -11,4 +11,4 @@
  * and limitations under the License.
  */
 /** The integration test for testing PyTorch specific features. */
-package integration;
+package ai.djl.pytorch.integration;

pytorch/pytorch-native/src/main/java/ai/djl/pytorch/jni/NativeHelper.java

@@ -0,0 +1,28 @@
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"). You may not use this file except in compliance
+ * with the License. A copy of the License is located at
+ *
+ * http://aws.amazon.com/apache2.0/
+ *
+ * or in the "license" file accompanying this file. This file 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 ai.djl.pytorch.jni;
+
+/** A helper class allows engine shared library to be loaded from different class loader. */
+public final class NativeHelper {
+
+    private NativeHelper() {}
+
+    /**
+     * Load native shared library from file.
+     *
+     * @param path the file to load
+     */
+    public static void load(String path) {
+        System.load(path); // NOPMD
+    }
+}

pytorch/pytorch-native/src/main/java/ai/djl/pytorch/jni/package-info.java

@@ -0,0 +1,14 @@
+/*
+ * Copyright 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License"). You may not use this file except in compliance
+ * with the License. A copy of the License is located at
+ *
+ * http://aws.amazon.com/apache2.0/
+ *
+ * or in the "license" file accompanying this file. This file 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.
+ */
+/** Contains helper class to load native shared library. */
+package ai.djl.pytorch.jni;