在java中构造嵌套的Tuple2

Question

我试图嵌套Tuple2，以便为我的图表上的每个顶点保存三个值：id，weight和label。

目前我有：

List<Tuple2<Object,Integer>> vertices = Lists.newArrayList(
         new Tuple2<Object,Integer>(1l,0),
         new Tuple2<Object,Integer>(2l,Integer.MAX_VALUE),
         new Tuple2<Object,Integer>(3l,Integer.MAX_VALUE),
         new Tuple2<Object,Integer>(4l,Integer.MAX_VALUE),
 );

我正在尝试构建嵌套的Tuple2，如下所示：

List<Tuple2<Object,Tuple2<Integer,String>>> vertices = Lists.newArrayList(
         new Tuple2<Object,Tuple2<Integer,String>>(1l,(0,"A")),
         new Tuple2<Object,Tuple2<Integer,String>>(2l,(Integer.MAX_VALUE,"B")),
         new Tuple2<Object,Tuple2<Integer,String>>(3l,(Integer.MAX_VALUE,"C")),
         new Tuple2<Object,Tuple2<Integer,String>>(4l,(Integer.MAX_VALUE,"D"))
);

但这给了我错误。

你能帮助我，找出问题所在。

谢谢

Answer 1

您收到错误，因为您没有初始化内部元组：

List<Tuple2<Object,Tuple2<Integer,String>>> vertices = Lists.newArrayList(
     new Tuple2<Object,Tuple2<Integer,String>>(
       1l, new Tuple2<Integer,String>(0,"A")
     ),
     new Tuple2<Object,Tuple2<Integer,String>>(
       2l, new (Integer.MAX_VALUE,"B")
     )
);