docs: @JRubyMethod
      public static IRubyObject node_import(IRubyObject self, IRubyObject node) {
          //             System.err.println("syck_genericresolver_node_import()");
          Ruby runtime = self.getRuntime();
          ThreadContext ctx = runtime.getCurrentContext();
          org.yecht.Node n = (org.yecht.Node)node.dataGetStructChecked();
          IRubyObject t = runtime.getNil();
          Extra x = (Extra)self.dataGetStruct();
  
          if(n.type_id != null) {
              t = runtime.newString(n.type_id);
          }
  
          switch(n.kind) {
          case Str:
              return x.scalar(t, n, ctx);
          case Seq:
              return x.sequence(t, n, ctx);
          case Map:
              return x.mapping(t, n, ctx);
          }
  
          return runtime.getNil();
      }