A `jrt` URL is a hierarchical URI with the syntax `jrt:/[$MODULE[/$PATH]]`. When using the `jrt` file system, a `java.net.URI` object can be created with the `java.nio.file.Path::toUri` method to encode a normalized path to a file in the `/modules` tree. A `jrt` URL cannot encode a path to a file in the `/packages` tree. The `jrt` file system provider has been changed in this release so that `toUri` fails with `IOError` when it is not possible to encode the file path as a `jrt` URI. This change might impact tools that assume a URI can be created to locate files in the `/packages` tree. Tools with paths to files in `/packages` can use the `toRealPath()` method to obtain the real path (in `/modules`) before attempting to convert the file path to a URI.