<script>
            $.jstree.defaults.core.themes.responsive = true;
$('#frmt').jstree({
    plugins: ["checkbox", "types"],
    "json_data":{
    "ajax" : {
        "url" : "D:pwebnodes.json"  // the URL to fetch the data. Use relative url if required
     }
},
       "types": {
        "file": {
            "icon": "jstree-file"
        }
    }
});
</script>

[
 {
  "id": "ajson1",
  "parent": "#",
  "text": "Simple root node"
},
{
  "id": "ajson2",
  "parent": "#",
  "text": "Root node 2"
}, {
  "id": "ajson3",
  "parent": "ajson2",
  "text": "Child 1"
}, {
  "id": "ajson4",
  "parent": "ajson2",
  "text": "Child 2"
}
]