Java's autoComplete does not work as expected?

v6
1

Why java autoComplete does not work

My code:

import {basicSetup, EditorView} from "codemirror"
import {java} from "@codemirror/lang-java"

const doc = ''

new EditorView({
  doc,
  extensions: [basicSetup, java()],
  parent: document.body
})
2

The @codemirror/lang-java package does not provide any autocompletion support.

3

So how can I support java autocompletion ？