UPDATE

src/main/java/tech/starwin/impl/HttpObserver.java

@@ -56,14 +56,14 @@ public abstract class HttpObserver<T> implements Observer<T> {
                     if (!isCanHandle(exception)) {
                         String body = exception.response().errorBody().string();
                         ResponseErrorBody responseErrorBody = new Gson().fromJson(body, ResponseErrorBody.class);
-                        onError(Error.SERVER_ERROR, "Server Exception: " + responseErrorBody.getMessage());
+                        onError(Error.SERVER_ERROR, responseErrorBody.getMessage());
                     }
                 } else if (msg.contains("java.lang.IllegalStateException")) {
                     onError(Error.APP_ERROR, "Program Exception");
                 } else if (msg.contains("body is null")) {
                     onSuccess(null);
                 } else {
-                    onError(Error.UNKNOW, "Unknow Exception: " + msg);
+                    onError(Error.UNKNOW,  msg);
                 }
 
             }