Recognize custom file extensions

src/extension.ts

@@ -208,7 +208,7 @@ export async function activate(context: ExtensionContext): Promise<ExtensionAPI>
 					{ scheme: 'untitled', language: 'java' }
 				],
 				synchronize: {
-					configurationSection: ['java', 'editor.insertSpaces', 'editor.tabSize'],
+					configurationSection: ['java', 'editor.insertSpaces', 'editor.tabSize', "files.associations"],
 				},
 				initializationOptions: {
 					bundles: collectJavaExtensions(extensions.all),
@@ -1061,7 +1061,7 @@ async function getTriggerFiles(): Promise<string[]> {
 function getJavaFilePathOfTextDocument(document: TextDocument): string | undefined {
 	if (document) {
 		const resource = document.uri;
-		if (resource.scheme === 'file' && resource.fsPath.endsWith('.java')) {
+		if (resource.scheme === 'file' && document.languageId === "java") {
 			return path.normalize(resource.fsPath);
 		}
 	}

src/fileEventHandler.ts

@@ -174,7 +174,25 @@ function getWillRenameHandler(client: LanguageClient) {
 }
 
 function isJavaFile(uri: Uri): boolean {
-    return uri.fsPath && uri.fsPath.endsWith(".java");
+    if (uri.fsPath && uri.fsPath.endsWith(".java")) {
+        return true;
+    }
+    let result = false;
+    const associations = workspace.getConfiguration().get("files.associations");
+    if (associations !== null) {
+        Object.keys(associations).forEach(pattern => {
+            const langId = associations[pattern];
+            if (langId === 'java' && pattern.startsWith('*.') && pattern.length > 2) {
+                const ext = pattern.substring(2);
+                if (!ext.includes('?') && !ext.includes('*')) {
+                    if (uri.fsPath && uri.fsPath.endsWith(`.${ext}`)) {
+                        result = true;
+                    }
+                }
+            }
+        });
+    }
+    return result;
 }
 
 async function isFile(uri: Uri): Promise<boolean> {

src/pasteAction.ts

@@ -39,8 +39,8 @@ export async function registerOrganizeImportsOnPasteCommand(): Promise<void> {
 	});
 
 	action.then((wasApplied) => {
-		const fileURI = editor.document.uri.toString();
-		if (wasApplied && fileURI.endsWith(".java")) {
+		if (wasApplied && editor.document.languageId === "java") {
+			const fileURI = editor.document.uri.toString();
 			const hasText: boolean = documentText !== null && /\S/.test(documentText);
 			if (hasText) {
 				// Organize imports silently to avoid surprising the user

src/utils.ts

@@ -226,6 +226,8 @@ export async function getJavaConfig(javaHome: string) {
 	const editorConfig = workspace.getConfiguration('editor');
 	javaConfig.format.insertSpaces = editorConfig.get('insertSpaces');
 	javaConfig.format.tabSize = editorConfig.get('tabSize');
+	const filesConfig = workspace.getConfiguration('files');
+	javaConfig.associations = filesConfig.get('associations');
 	const isInsider: boolean = version.includes("insider");
 	const androidSupport = javaConfig.jdt.ls.androidSupport.enabled;
 	switch (androidSupport) {