question: public static String extractHostId ( String hostId ) { AssertUtil . assertNotNull ( hostId , "hostId" ) ; int idx = hostId . indexOf ( HOST_ID_TENANT_SEPARATOR ) ; String id = hostId ; if ( idx != - 1 ) { id = hostId . substring ( idx + HOST_ID_TENANT_SEPARATOR . length ( ) ) ; } return id ; }
target:  Extracts the id from a host id