René's URL Explorer Experiment

{"@context":"https://schema.org","@type":"DiscussionForumPosting","headline":"Setting userProject from NIO FileSystemProvider","articleBody":"I'm happy to see that [requester-pays support was just added](https://github.com/GoogleCloudPlatform/google-cloud-java/issues/3221)!\r\n\r\nafaict, I can't set the `userProject` in a `CloudStorageFileSystemProvider` that gets instantiated via the Java NIO `FileSystemProvider` machinery, which uses `Class.newInstance()` to invoke the nullary constructor:\r\n\r\n```java\r\nimport java.net.URI;\r\nimport java.nio.file.Paths;\r\nimport java.nio.file.Files;\r\nFiles.newDirectoryStream(Paths.get(new URI(\"gs://\u003cbucket\u003e\")))\r\n```\r\n\r\nthrows:\r\n```\r\ncom.google.cloud.storage.StorageException: Bucket is requester pays bucket but no user project provided.\r\n  at com.google.cloud.storage.spi.v1.HttpStorageRpc.translate(HttpStorageRpc.java:220)\r\n  at com.google.cloud.storage.spi.v1.HttpStorageRpc.list(HttpStorageRpc.java:347)\r\n  at com.google.cloud.storage.StorageImpl$8.call(StorageImpl.java:299)\r\n  …\r\n```\r\n\r\nIs there a way to set the user-project, other than as a ctor param?\r\n- an environment variable would seem easiest\r\n  - afaict there's no standard mechanism for doing that across GCS libraries in various languages\r\n  - perhaps it's still ok to add one here\r\n- a setter would help a bit\r\n  - I'll be mainly using it from [hammerlab/path-utils](https://github.com/hammerlab/path-utils), where I (unfortunately) have code to [reach into the `installedProviders` and modify the providers for a given URI scheme](https://github.com/hammerlab/path-utils/blob/1.5.0/src/main/scala/org/hammerlab/paths/FileSystems.scala#L128-L145)\r\n  - a setter would at least save me from a second reflection hack to reach ","author":{"url":"https://github.com/ryan-williams","@type":"Person","name":"ryan-williams"},"datePublished":"2018-07-17T15:28:00.000Z","interactionStatistic":{"@type":"InteractionCounter","interactionType":"https://schema.org/CommentAction","userInteractionCount":4},"url":"https://github.com/3475/google-cloud-java/issues/3475"}