12 examples
Unhandled exception
Exception occurs without proper handling.
[ FAQ1 ]
What is an unhandled exception?
An unhandled exception occurs when a program encounters an error or unexpected condition without having any code to explicitly handle it. Such exceptions propagate through the application, eventually reaching the runtime environment and causing the application to crash or terminate abruptly. Common examples include null pointer exceptions, file access errors, or network failures that aren’t wrapped in appropriate error-handling structures. Unhandled exceptions negatively impact user experience and reliability, often resulting in data loss or unstable application behavior.
[ FAQ2 ]
How to catch unhandled exceptions
To catch unhandled exceptions, use structured error-handling mechanisms such as
try-catch
blocks or equivalent constructs provided by the programming language. Implement a global error handler or exception handler that can intercept unexpected exceptions, log useful diagnostic information, and gracefully recover or terminate the application. Ensure critical sections and operations prone to errors are protected by localized exception handling, allowing your application to manage errors proactively. Regularly review logs and analytics to identify patterns of unhandled exceptions and continuously refine error-handling strategies for improved reliability.diff block
greptile
style: Missing error handling for the fetch operation. If the network request fails or the GitHub URL is unavailable, this will throw an unhandled exception.
```suggestion
+ try {
const response = await fetch(
'https://raw.githubusercontent.com/GTBitsOfGood/design-system/refs/heads/main/src/styles/globals.css'
);
+ if (!response.ok) {
+ throw new Error(`Failed to fetch styles: ${response.status} ${response.statusText}`);
}
const styles = await response.text();
+ } catch (error) {
+ console.error('Failed to download the BOG theme:', error.message);
+ console.error('You may need to manually create the stylesheet.');
return;
}
```
diff block
greptile
logic: API call does not check if response.ok. Consider checking response.ok and handling error responses to avoid unhandled exceptions.
```suggestion
const response = await fetch(`https://hnrss.org/newest.jsonfeed?points=500`, {
headers: {
"User-Agent": `Hacker News Extension, Raycast/${environment.raycastVersion} (${os.type()} ${os.release()})`,
},
});
+ if (!response.ok) {
+ throw new Error(`HTTP ${response.status}: ${response.statusText}`);
}
```
diff block
greptile
logic: Missing try/catch for date parsing - invalid date format will cause unhandled exception
suggested fix
rollout_date_str = options.get("rollout_date")
+ try:
rollout_date = datetime.strptime(rollout_date_str, "%Y-%m-%d").date()
+ except ValueError:
+ self.stdout.write(self.style.ERROR(f"Invalid date format. Please use YYYY-MM-DD format."))
+ return
diff block
greptile
logic: getSourceIcons lacks try-catch error handling and could throw unhandled exceptions
diff block
greptile
style: Missing try/catch around token verification - could throw unhandled exceptions
suggested fix
async authenticateToken(token: string): Promise<FirebaseUser | null> {
+ try {
const decoded = await admin.auth().verifyIdToken(token);
return decoded;
+ } catch (error) {
+ return null;
}
}
diff block
greptile
logic: readFile() needs try-catch block to handle file system errors gracefully. Currently could throw unhandled exceptions.
suggested fix
function readFile(path?: string) {
if (!path) {
return "";
}
try {
return fs.readFileSync(path, "utf-8");
} catch (error) {
+ showFailureToast("Failed to read file", { title: error instanceof Error ? error.message : String(error) });
return "";
}
}
diff block
greptile
logic: initializeQuickLink is called but not wrapped in try-catch, which could cause unhandled exceptions if there are issues with the quick link initialization
suggested fix
+ try {
+ await initializeQuickLink(lastProjectId);
+ } catch (error) {
+ showFailureToast(error, { title: "Could not initialize quick link" });
+ }
diff block
greptile
logic: Throwing an error here will cause an unhandled exception. Consider using `showCustomToast` instead and returning early.
diff block
greptile
logic: Missing error handling for the fetch request. If the API is unavailable or returns an error status, this will throw an unhandled exception.
diff block
greptile
logic: Missing error handling for image loading failures. If either image can't be read, this will throw an unhandled exception.
diff block
greptile
logic: Missing try/catch block around gRPC call could lead to unhandled exceptions
suggested fix
+ try {
const config = this.fileConfigDBService.getConfig({
id: id,
environment: apiKey.environment,
});
+ return new FileConfigResponse(await lastValueFrom(config));
+ } catch (error) {
+ throw new BadRequestException('Failed to fetch file configuration');
}
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