String(如:IP)与long型互转

/**
     * IP(String) 转 Long
     * string ip to long
     * */
    public long ipStrToLong(String ipaddress) {  
        long[] ip = new long[4];
        int i = 0;
        for(String ipStr : ipaddress.split("\\.")){
            ip[i] = Long.parseLong(ipStr);
            i++;
        }  
        return (ip[0] << 24) + (ip[1] << 16) + (ip[2] << 8) + ip[3];  
    }
    /**
     * Long 转 IP(String)
     * ip long to String
     * */
    public String iplongToIp(long ipaddress) {  
        StringBuffer sb = new StringBuffer("");
        sb.append(String.valueOf((ipaddress >>> 24)));
        sb.append(".");
        sb.append(String.valueOf((ipaddress & 0x00FFFFFF) >>> 16));
        sb.append(".");
        sb.append(String.valueOf((ipaddress & 0x0000FFFF) >>> 8));
        sb.append(".");
        sb.append(String.valueOf((ipaddress & 0x000000FF)));
        return sb.toString();
    }