如何在flink流中使用classloader？

Question

以下是我的流式代码。我希望地图方法从外部jarfile接收我的客户方法

       public void run() throws Exception {
        StreamExecutionEnvironment env = StreamExecutionEnvironment.getExecutionEnvironment();

        DataStreamSource<String> ds = env.socketTextStream("localhost",9999);

 URL[] urls = {new URL("file:///Users/django/workspace/test01/target/test01-1.0.jar")};
        URLClassLoader urlClassLoader = new URLClassLoader(urls);
        Class say = urlClassLoader.loadClass("com.fanqizha.FanqizhaMap");


        RichMapFunction parser = (RichMapFunction)say.getConstructor().newInstance();

        SingleOutputStreamOperator map = ds.map(parser);

        map.print();

        env.execute();
    }

但是我得到一个例外

org.apache.flink.streaming.runtime.tasks.StreamTaskException: Cannot load user class: com.fanqizha.FanqizhaMap

我的flink版本是1.7.1