Apache flink 弗林克：当我添加仪表时，构建失败了

无法使用仪表，生成失败：

 def open(configuration: Configuration) {
  getRuntimeContext()
    .getMetricGroup()
    .gauge("RecordConverter.latency", new Gauge[Int]() {
      @Override
      def getValue(): Int = {
        return latency;
      }
    });
   }

============================================================

error: overloaded method value gauge with alternatives:
[ERROR]   [T, G <: org.apache.flink.metrics.Gauge[T]](x$1: String,x$2: G)G <and>
[ERROR]   [T, G <: org.apache.flink.metrics.Gauge[T]](x$1: Int, x$2: G)G
[ERROR]  cannot be applied to (String, org.apache.flink.metrics.Gauge[Int])
[ERROR]         .gauge("RecordConverter.latency", new Gauge[Int]() {
[ERROR]          ^

错误：重载方法值量表，带有备选值：
[错误][T，G您必须显式设置类型，如下所示：

 .gauge[Int, Gauge[Int]]("RecordConverter.latency"...