Create file name using date and time

I hope you could help me, I'm trying to call in the date from another class and looks like "2011-03-09 06-57-40", I want to use this to create the file below but everytime I do when the output runs it creates a new file as it re-runs calling the dat(). I know what's going wrong I'm just not sure how to fix it, I want to permently writw to the same file. I hope this makes sense? :/

Thank you for any help in advance :)

    date d = new date();
    String  cdate = d.date();


    String f = h;

    try{
        PrintWriter out = new PrintWriter(new BufferedWriter(new FileWriter(cdate开发者_运维知识库 + ".tsv", true)));
        out.print(f);
        out.print("\t");
        out.close();
    }catch (IOException e){
    }

To create a file named the current date/time:

Date date = new Date() ;
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd HH-mm-ss") ;
File file = new File(dateFormat.format(date) + ".tsv") ;
BufferedWriter out = new BufferedWriter(new FileWriter(file));
out.write("Writing to file");
out.close();

This one probably much easier. Only one line of a code to assign the name of the file as date and time.

String out = new SimpleDateFormat("yyyy-MM-dd hh-mm-ss'.tsv'").format(new Date());

I'll try and answer all the same. To obtain a date or time string in the most controlled manner possible use the following code

Calendar cal = Calendar.getInstance();
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
String dateStr = dateFormat.format(cal.getTime());

Look up http://download.oracle.com/javase/6/docs/api/java/text/SimpleDateFormat.html . It might help with understanding. You can also add hour/minute or what you need to the formatted String.

Another option might be to always set the "lower" fields like milliseconds, seconds, minutes in the Calendar to zero.

cal.set(Calendar.MINUTE,0);

If you are retrieving your date from another class and cannot directly create a calendar you can also put the date into the calendar (note: for just formatting you don't need the calendar)

cal.setTime(date);

Maybe this helps getting more control of the created filename / file.

It will be just a bit more efficient - only one SimpleDateFormat and Date object for each file, as well as no String concatenation.

private  final static String getDateTime()  
{  
    DateFormat df = new SimpleDateFormat("yyyy-MM-dd_hh:mm:ss");  
    df.setTimeZone(TimeZone.getTimeZone("PST"));  
    return df.format(new Date());  
}  

public class BELogs {

    private final static Logger logger = Logger.getLogger(BSELogs.class
            .getName()); 

             boolean makeDir = false;
             Date date = new Date();
             SimpleDateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy") ;
             String curDate =dateFormat.format(date);
             FileHandler fh;     

               public BSELogs()  {

         try {  

             File file = new File("/home//Desktop/Logs "+curDate);
             makeDir = file.mkdir();
             fh = new FileHandler(file+"/MyLogFile.log "+curDate,true);  
             logger.addHandler(fh);
             // Set the logger level to produce logs at this level and above.
             logger.setLevel(Level.FINE);
             SimpleFormatter formatter = new SimpleFormatter();  
             fh.setFormatter(formatter);  

          } catch (SecurityException ex) {  **strong text**
             ex.printStackTrace();  
          } catch (IOException e) {  
               e.printStackTrace();  
           }  

    logger.info("Data Log Genrated............"); 

      }
}