java获取本地多网卡ip

public  String getLocalHostName() {
        String hostName;
        try  {
            InetAddress addr = InetAddress.getLocalHost();
            hostName = addr.getHostName();
        }  catch  (Exception ex) {
            hostName =  "" ;
        }
        return  hostName;
    }

public  String[] getAllLocalHostIP() {
    String[] ret =  null ;
    try  {
        String hostName = getLocalHostName();
        if  (hostName.length() >  0 ) {
            InetAddress[] addrs = InetAddress.getAllByName(hostName);
            if  (addrs.length >  0 ) {
                ret =  new  String[addrs.length];
                for  ( int  i =  0 ; i < addrs.length; i++) {
                    ret[i] = addrs[i].getHostAddress();
                }
            }
        }

        }  catch  (Exception ex) {
            ret =  null ;
        }
        return  ret;
    }