Handle snippets when opened (empty) Java file triggers activation.

- When extension is activated by opened empty Java source file, the
  snippet insertion logic has yet to be registered so boilerplate type
  declaration snippet cannot be applied
- Recover by detecting opened, active Java source file and create the
  appropriate type declaration

Signed-off-by: Roland Grunberg <rgrunber@redhat.com>

Author: rgrunber

src/extension.ts

@@ -577,6 +577,18 @@ export async function activate(context: ExtensionContext): Promise<ExtensionAPI>
 				commands.executeCommand('setContext', 'java:serverMode', event);
 			});
 
+			// extension activated by creation of new Java file ?
+			// type declaration snippet handler registered late so adjust the file here
+			apiManager.getApiInstance().serverReady().then(async () => {
+				const te = window.activeTextEditor?.document;
+				if (te && te.getText().trim().length === 0) {
+					fileEventHandler.setServerStatus(true);
+					fileEventHandler.handleNewJavaFiles({
+						files: [te.uri]
+					});
+				}
+			});
+
 			if (serverMode === ServerMode.hybrid && !await fse.pathExists(path.join(workspacePath, ".metadata", ".plugins"))) {
 				const config = getJavaConfiguration();
 				const importOnStartupSection: string = "project.importOnFirstTimeStartup";

src/fileEventHandler.ts

@@ -27,7 +27,7 @@ export function registerFileEventHandlers(client: LanguageClient, context: Exten
     }
 }
 
-async function handleNewJavaFiles(e: FileCreateEvent) {
+export async function handleNewJavaFiles(e: FileCreateEvent) {
     const emptyFiles: Uri[] = [];
     const textDocuments: TextDocument[] = [];
     for (const uri of e.files) {