Optimize js spider

quickjs/src/main/java/com/fongmi/quickjs/crawler/Spider.java

@@ -25,7 +25,6 @@ import java.util.HashMap;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.Callable;
-import java.util.concurrent.CompletableFuture;
 import java.util.concurrent.ExecutorService;
 import java.util.concurrent.Executors;
 import java.util.concurrent.Future;
@@ -52,7 +51,7 @@ public class Spider extends com.github.catvod.crawler.Spider {
     }
 
     private Object call(String func, Object... args) throws Exception {
-        return CompletableFuture.supplyAsync(() -> Async.run(jsObject, func, args), executor).join().get();
+        return submit(() -> Async.run(jsObject, func, args)).get().get();
     }
 
     @Override

quickjs/src/main/java/com/fongmi/quickjs/utils/Async.java

@@ -67,7 +67,8 @@ public class Async {
     };
 
     private final JSCallFunction onError = args -> {
-        future.complete(null);
+        String msg = args != null && args.length > 0 && args[0] != null ? args[0].toString() : "";
+        future.completeExceptionally(new Exception(msg));
         return null;
     };
 }