{"action":"opened","issue":{"url":"https://api.github.com/repos/google/guava/issues/2452","repository_url":"https://api.github.com/repos/google/guava","labels_url":"https://api.github.com/repos/google/guava/issues/2452/labels{/name}","comments_url":"https://api.github.com/repos/google/guava/issues/2452/comments","events_url":"https://api.github.com/repos/google/guava/issues/2452/events","html_url":"https://github.com/google/guava/issues/2452","id":148202943,"number":2452,"title":"Potential problems of MutableGraph vs optional mutation methods on Graph","user":{"login":"jbduncan","id":2482228,"avatar_url":"https://avatars.githubusercontent.com/u/2482228?v=3","gravatar_id":"","url":"https://api.github.com/users/jbduncan","html_url":"https://github.com/jbduncan","followers_url":"https://api.github.com/users/jbduncan/followers","following_url":"https://api.github.com/users/jbduncan/following{/other_user}","gists_url":"https://api.github.com/users/jbduncan/gists{/gist_id}","starred_url":"https://api.github.com/users/jbduncan/starred{/owner}{/repo}","subscriptions_url":"https://api.github.com/users/jbduncan/subscriptions","organizations_url":"https://api.github.com/users/jbduncan/orgs","repos_url":"https://api.github.com/users/jbduncan/repos","events_url":"https://api.github.com/users/jbduncan/events{/privacy}","received_events_url":"https://api.github.com/users/jbduncan/received_events","type":"User","site_admin":false},"labels":[],"state":"open","locked":false,"assignee":null,"milestone":null,"comments":0,"created_at":"2016-04-13T22:38:44Z","updated_at":"2016-04-13T22:38:44Z","closed_at":null,"body":"I noticed recently that `MutableGraph` was split away from `Graph`, so I was curious as to why the Java Collections framework didn't do the same. I googled it up and found [this StackOverflow answer](http://programmers.stackexchange.com/a/289372), which I think gives a very convincing explanation as to why Sun Microsystems opted to go for optional, `UnsupportedOperationException`-based mutation methods rather than mutable sub-interfaces.\r\n\r\nHas the Guava team considered the advantages and disadvantages of both approaches?"}}