java - Picking specif data from .txt and writing as columns in csv -

this part of .txt:

thu mar 28 12:18:28 edt 2013

memfree: 601836 kb

linux 2.6.18-308.el5 (cwapp1.conceptwave.com) 03/28/2013

avg-cpu: %user %nice %system %iowait %steal %idle 0.15 0.00 0.05 0.02 0.00 99.79

========================

thu mar 28 12:18:38 edt 2013

memfree: 598312 kb

linux 2.6.18-308.el5 (cwapp1.conceptwave.com) 03/28/2013

avg-cpu: %user %nice %system %iowait %steal %idle 0.15 0.00 0.05 0.02 0.00 99.79

========================

i need read date, memory free , %idle, , write 2 csv files 2 columns. 1 date , memory, , other date , %idle. have written code reads data , append 3 lists. how write them 2 csv files such fulfill requirement?

thanks in advance.

my code:

list<string> datetime = new arraylist<string>(); list<string> memfree = new arraylist<string>();  list<string> pidle = new arraylist<string>();  public static void main(string[] args)  {     // todo auto-generated method stub  }  public void readfile(string file) {      try     {         bufferedreader br = new bufferedreader(new filereader(file));         string str = null;           try          {             while((str=br.readline()) != null)             {                 string[] st = str.split("\\s+");                    if (st[0] == "memfree:")                     memfree.add(st[1]);                   if(isdouble(st))                     pidle.add(st[4]);                                     if(isdate(str))                 {                     string substr = str.substring(0, 15);                     datetime.add(substr);                  }               }         }                  {             br.close();          }     }      catch(filenotfoundexception e)     {         system.out.println("file not found!");     }      catch(ioexception e)     {         system.out.println(e);     }  }  public boolean isdate(string str) {     dateformat df = new simpledateformat("e m d");      try     {         string substr = str.substring(0, 8);         @suppresswarnings("unused")         date currentdate = df.parse(substr);          return true;      }      catch(parseexception e)     {         return false;      } }  public boolean isdouble(string[] st) {      try     {         (int = 0; < st.length;)         {             @suppresswarnings("unused")             double num = double.parsedouble(st[i]);              return true;         }      }      catch(illegalargumentexception ex)     {         return false;      }      return false; }  public void writetocsv(list<string> datetime, list<string> memfree, list<string> pidle) {     //unfinished - need help!     string datesepval = "";      if(datetime != null && memfree != null)     {         iterator<string> iter = datetime.iterator();           while(iter.hasnext())         {             datesepval += iter.next() + ",";          }          if(datesepval.endswith(","))         {             datesepval = datesepval.substring(0, datesepval.lastindexof(","));         }     }      if(datetime != null && pidle !=null)     {         //todo     }  } 

writing file reading, other way around:

try (bufferedwriter writer = new bufferedwriter(new filewriter("delete.me"))) {     writer.write("something");     writer.newline(); } 

if want have new line each extracted date & memory value, this:

public void writetocsv(list<string> datetime, list<string> memfree) throws ioexception {     try (bufferedwriter writer = new bufferedwriter(new filewriter("delete.me"))) {         if(datetime == null || memfree == null)             return;          iterator<string> memfrees = memfree.iterator();          (string dt: datetimes) {             if (!memfrees.hasnext())                 return;             writer.write(dt + "," + memfrees.next());             writer.newline();         }     } } 

but m sach suggested, may want @ framework doing things you.