Manual get authenticate code from box.com Java
Create class ApiClientConfig to using this function
ApiClientConfig config = new ApiClientConfig(HOST,USERNAME, PASSWORD, CLIENT_ID, CLIENT_SECRET);
After that call function
BoxApiClient client = new BoxApiClient();
String authorizeCode = client.getAuthorizeCode(config);
After that using BoxSDK (https://github.com/box/box-java-sdk) to authorize