quarkusio/quarkus · error · RuntimeException

Failed to translate

Error message

Failed to translate 

What it means

Thrown from PathTreeClassPathElement.getUrl when translating the element's internal path into a java.net.URL fails with MalformedURLException, wrapped in a RuntimeException. This method builds runtime URLs for classpath elements (handling escaping of special characters like '?'). Failure means the resource path cannot be represented as a valid URL.

Source

Thrown at independent-projects/bootstrap/core/src/main/java/io/quarkus/bootstrap/classloading/PathTreeClassPathElement.java:257

                    // (one with a trailing slash and one without) for same resource
                    if (uri.getPath() != null && uri.getPath().endsWith("/")) {
                        String uriStr = uri.toString();
                        url = new URL(uriStr.substring(0, uriStr.length() - 1));
                    } else {
                        url = uri.toURL();
                    }
                    if (url.getQuery() != null) {
                        //huge hack to work around a JDK bug. ZipPath does not escape properly, so if there is a ?
                        //in the path then it ends up in the query string and everything is screwy.
                        //if there are multiple question marks the extra ones end up in the path and not the query string as you would expect
                        url = new URL(url.getProtocol(), url.getHost(), url.getPort(),
                                url.getPath().replaceAll("\\?", "%3F") + "%3F" + url.getQuery());
                    }
                    return this.url = url;
                }
                return url = apply(this::getUrl);
            } catch (MalformedURLException e) {
                throw new RuntimeException("Failed to translate " + path + " to URL", e);
            } finally {
                lock.readLock().unlock();
            }
        }

        /**
         * URL for this resource in a given {@link OpenPathTree}.
         * If the path tree contains the resource, its URL is returned.
         * Otherwise, the method returns null.
         *
         * @param tree path tree to look for the resource in
         * @return resource URL if it exists in a given path tree or null if it does not
         */
        private URL getUrl(OpenPathTree tree) {
            return tree.apply(name, Resource::getUrl);
        }

        /**

View on GitHub (pinned to e1c734241f)

Solutions

1. Rename the offending directory/jar to remove reserved URL characters ('?', '#', spaces)
2. Inspect the cause MalformedURLException to identify the offending character
3. Run the application from a conventional location (plain alphanumeric path)

Example fix

// before
/path/to/my?app/runner.jar // '?' breaks URL translation
// after
/path/to/my_app/runner.jar

String p = path.toString();
if (p.contains("?") || p.contains("#") || p.contains(" ")) {
    throw new IllegalStateException("path contains URL-reserved characters: " + p);
}

When it happens

Trigger: Calling getUrl() on a PathTreeClassPathElement whose path contains characters that break URL parsing and are not correctly escaped (e.g. '?', spaces) so that MalformedURLException is thrown.

Common situations: Running from directories/jars whose names include '?' or other reserved URL characters; unusual build output locations.

Related errors

• Unable to create protection domain for
• Invalid URL:
• java.io.UncheckedIOException
• Unable to create protection domain for ${jarPath}
• Failed to create output directory for generated sources: %s

AI-assisted analysis of quarkusio/quarkus@e1c734241f (2026-09-05). Data as JSON: /api/errors/21c9e77cf60017b8. Report an issue: GitHub.