[Java] Fix bug when actor creation task fails (#3740)

* [Java] Fix bug when actor creation task fails

* remove imports

java/test/src/main/java/org/ray/api/test/FailureTest.java

@@ -0,0 +1,63 @@
+package org.ray.api.test;
+
+import org.junit.Assert;
+import org.junit.Test;
+import org.ray.api.Ray;
+import org.ray.api.RayActor;
+import org.ray.api.RayObject;
+import org.ray.api.exception.RayException;
+
+public class FailureTest extends BaseTest {
+
+  private static final String EXCEPTION_MESSAGE = "Oops";
+
+  public static int badFunc() {
+    throw new RuntimeException(EXCEPTION_MESSAGE);
+  }
+
+  public static class BadActor {
+
+    public BadActor(boolean failOnCreation) {
+      if (failOnCreation) {
+        throw new RuntimeException(EXCEPTION_MESSAGE);
+      }
+    }
+
+    public int func() {
+      throw new RuntimeException(EXCEPTION_MESSAGE);
+    }
+  }
+
+  private static void assertTaskFail(RayObject<?> rayObject) {
+    try {
+      rayObject.get();
+      Assert.fail("Task didn't fail.");
+    } catch (RayException e) {
+      e.printStackTrace();
+      Throwable rootCause = e.getCause();
+      while (rootCause.getCause() != null) {
+        rootCause = rootCause.getCause();
+      }
+      Assert.assertTrue(rootCause instanceof RuntimeException);
+      Assert.assertEquals(rootCause.getMessage(), EXCEPTION_MESSAGE);
+    }
+  }
+
+  @Test
+  public void testNormalTaskFailure() {
+    assertTaskFail(Ray.call(FailureTest::badFunc));
+  }
+
+  @Test
+  public void testActorCreationFailure() {
+    RayActor<BadActor> actor = Ray.createActor(BadActor::new, true);
+    assertTaskFail(Ray.call(BadActor::func, actor));
+  }
+
+  @Test
+  public void testActorTaskFailure() {
+    RayActor<BadActor> actor = Ray.createActor(BadActor::new, false);
+    assertTaskFail(Ray.call(BadActor::func, actor));
+  }
+}
+