Why can't I read / proc / net / xt _qtaguid / stats correctly using FileReader in Android ICS

Question

I want to read / proc / net / xt _qtaguid / stats in Android ICS, which records all the traffic parameters of interfaces and applications. following code snippet:

String line = null;
BufferReader reader = new BufferedReader(new FileReader(new File("/proc/net/xt_qtaguid/stats")));

line = reader.readLine();/*Here I can read the 1st line correctly, it return "idx  iface acct_tag_hex..."*/
splitLine(line, keys);
line = reader.readLine();//!!!!!Read next line, it returns null!!!!!!

If I cat this file, it will show:

IDX IFACE acct_tag_hex uid_tag_int cnt_set rx_bytes rx_packets tx_bytes tx_packets rx_tcp_bytes rx_tcp_packets rx_udp_bytes rx_udp_packets rx_other_bytes rx_other_packets tx_txtp_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_t_tx_tc_tc

2 rmnet0 0x0 0 0 6266 105 8882 121 1428 30 4838 75 0 0 208 4 2552 44 6122 73

3 rmnet0 0x0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

4 rmnet0 0x0 1000 0 0 0 2262 39 0 0 0 0 0 0 0 0 2262 39 0 0

5 rmnet0 0x0 1000 1 0 0 290 5 0 0 0 0 0 0 0 0 0 290 5 0 0

6 rmnet0 0x0 10004 0 1000 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0

7 rmnet0 0x0 10004 1 20177 36 7037 81 20177 36 0 0 0 0 7037 81 0 0 0 0

, NetworkStatsFactory.java( Android) . , :

try{
    NetworkStats stats = new NetworkStatsFactory().readNetworkStatsDetail(10004);
    stats.size();//size is ZERO!
}
catch(IllegalStateException e){
    //Do nothing
}

Google ​​ ?:)

Answer 1

: read_proc uid, .