Delete all files not modified in last ten days

Question

I have a folder where I keep log files and I have a job scheduled to run each day to delete old logs.

What's a good way to delete old log files?

Currently, I loop through the directory to read files

File[] listOfFiles = srcFolder.listFiles(fileNameFilter); // this makes an array of files which match a filter I created
for(int i=listOfFiles.length-1; i>0; i--){ // leave at least one file

    // listOfFiles[i].lastModified() - in last ten days?
    if( what condition ?){
        try {
            listOfFiles[i].delete();
        } catch(Exception e){

        }
    }
}

I'm thinking

 if(listOfFiles[i].lastModified() < tenDaysAgoMS) // where tenDaysAgoMS is the milliseconds ten days ago, but how to implement?

Answer 1

First, you have to subtract the last-modified property to the current time. See Calendar.getTimeInMillis() and File.lastModified().

Then, you can convert days to milliseconds by multiplying them to 1000 * 60 * 60 * 24.

1. 1000ms = 1s

2. 60s = 1m

3. 60m = 1h

4. 24h = 1d

---

long now = Calendar.getInstance().getTimeInMillis();
long oneDay = 1000L * 60L * 60L * 24L;
long tenDays = 10L * oneDay;

File log = listOfFiles[i];
long diff = now - log.lastModified();
if (diff > tenDays) {
    log.delete();
}