dataTables.bootstrap 如何显示中文

$('#table_cust').DataTable({
    "oLanguage": {
        "sUrl": "/assets/vendors/page_zh_CN.json"
    },

page_zh_CN.json 内容如下：

{
  "sProcessing":   "处理中...",
  "sLengthMenu":   "_MENU_ 记录/页",
  "sZeroRecords":  "没有匹配的记录",
  "sInfo":         "显示第 _START_ 至 _END_ 项记录，共 _TOTAL_ 项",
  "sInfoEmpty":    "显示第 0 至 0 项记录，共 0 项",
  "sInfoFiltered": "(由 _MAX_ 项记录过滤)",
  "sInfoPostFix":  "",
  "sSearch":       "过滤:",
  "sUrl":          "",
  "oPaginate": {
    "sFirst":    "首页",
    "sPrevious": "上页",
    "sNext":     "下页",
    "sLast":     "末页"
  }
}