Status bar keeps showing "100% Starting Java Language Server"

[Eskibear]

The language server has been launched successfully, and all features are ready, but the message is pinned on the status bar. It's probably a racing condition, and it's not stably reproducible.

I've done some investigation to print out the notifications, and I find the sequence on my machine is usually as following:

[Starting]	30% Starting Java Language Server 
[Starting]	35% Starting Java Language Server 
[Starting]	100% Starting Java Language Server 
[Starting]	100% Starting Java Language Server 
[Started]	Ready
[Starting]	100% Starting Java Language Server 

You may notice that after a "started" notification, it still receives a "starting" notification.

But when I met the issue, the log looks like the following, indicating that previous notifications are not received by the callback.

[Starting]	100% Starting Java Language Server

So I guess if it's because: immediately after the languageClient onReady, the previous notifications have been sent, before the callback completes the registration.

[trancexpress]

I'm not sure if this is the right place, or if I should open a new issue. But this issue seems at least related.

We are trying out vscode-java and org.eclipse.jdt.ls, we are running into a somewhat similar issue. Among other things, we are trying to "attach" VS Code to our running Eclipse process. Whenever we try to attach VS Code for a 2nd time to the same server (e.g. we restarted VS Code or the extension host process restarted), we see hanging status: "Activating..."

This seems to be due to this code:

	await standardClient.initialize(context, requirements, clientOptions, workspacePath, jdtEventEmitter);
	standardClient.start().then(async () => {
		await new Promise(f => setTimeout(f, 1000));
		standardClient.registerLanguageClientActions(context, await fse.pathExists(path.join(workspacePath, ".metadata", ".plugins")), jdtEventEmitter);
	});
	serverStatusBarProvider.setBusy("Activating...");

When I debug the server code, both notifications for Started and ServiceReady are sent. But only ServiceReady is received in the languageClient.onNotification() function.

If I delay the registration of the listener, both notifications are missed:

diff --git a/src/extension.ts b/src/extension.ts
index 3af80d7..17442c1 100644
--- a/src/extension.ts
+++ b/src/extension.ts
@@ -793,6 +793,7 @@ async function startStandardServer(context: ExtensionContext, requirements: requ
        }
        await standardClient.initialize(context, requirements, clientOptions, workspacePath, jdtEventEmitter);
        standardClient.start().then(async () => {
+               await new Promise(f => setTimeout(f, 1000));
                standardClient.registerLanguageClientActions(context, await fse.pathExists(path.join(workspacePath, ".metadata", ".plugins")), jdtEventEmitter);
        });
        serverStatusBarProvider.setBusy("Activating...");

I.e. if the server is fast to send its notifications (which is the case for what we are trying), notifications can be missed.

Any advice on what needs to change in vscode-java to prevent this? Unfortunately Typescript and VS Code extensions are both very new to me. Can languageClient.onNotification() be registered before the standardClient.start() call? Even before the initialize call, just to be sure notifications are not missed.