using grant_type as part of auth2.0 required values

[mapyourown]

For getting the access token, I pass in for the rest endpoint (client_id, client_secret, grant_type, account_id). I am trying using the java sdk and in the properties file I didn't see the grant_type. Because I am using a shared instance and I need to pass grant_type. Do I need to add on the properties files a grant_type and modify the code to use this value? Just wondering how other developer way around this issue?