How to pick the multiples based on file size

Question

Hi All,
my sender file adapter needs to pick up 5 files based on file size.
for example 1file size is 500kb,2nd file size 300kb,3rd file size 400kb, 4file size 100kb and 5file size 600kb.
here my requirement is, my file adapter needs to pick in the below order like 5th file,1st file,3rd file 2nd file and 4th file.
means based on file size, i need to pick up my file adapter.
could you please ang inputs on this requirement.
Thanks & Regards,
AVR

Answer 1

Hi AVR,
for case 2:
1. At specific time each day  "23:58:00" hours ,count the number of files in directory say "c:\apps\acm".
2. sort the files on basis of their size.
3. place the files one by one after definite  time interval (more than polling time of the sender communication channel).
in target directory say "c:\apps\acm1" from where PI server  picks up the files for further processing. The file with smallest size is placed last.
4. In this case you need to ensure all files are present in the directory "c:\apps\acm" before "23:58:00" hours.
for case 2  java code
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.util.Calendar;
import java.util.GregorianCalendar;
public class sortFilesOnSpecificTime {
* @param args
public static void main(String[] args) {
// TODO Auto-generated method stub
try
* In Unix/Linux OS, dir1="/usr/apps/test"  etc
int pollingInterval=10,sleepTime=1*60;
String dir1="c:\\apps\\acm";
String dir2="c:\\apps\\acm1";
File fread=new File(dir1);
File fwrite=new File(dir2);
if(fread.canRead()==false)
System.out.println("error: "+dir1+" does not have read permission. Program Terminates.");
return;
if(fwrite.canWrite()==false)
System.out.println("error: "+dir2+" does not have write permission. Program Terminates.");
return;
String fileNames[],fileNamesOut[];
long fileSize[];
int i,j;
byte b[];
int t=4;
Calendar cal;
int hour24,min,fileCopyHour=23,fileCopyMin=58;
long waitSeconds=1,currentTime=0;
while(t>0)
cal = new GregorianCalendar();
hour24 = cal.get(Calendar.HOUR_OF_DAY);     // 0..23
min = cal.get(Calendar.MINUTE);             //0..59
System.out.println("current time="+hour24+":"+min);
/*loop unless time reaches a specific predetermined value
* predetermined values are provided by values
* fileCopyHour=8,fileCopyMin=30 i.e say 08:30 hours
currentTime=(hour24*60+min)*60;
waitSeconds=(fileCopyHour*60+fileCopyMin)*60 - currentTime;
if(waitSeconds>0)
* in case you wanna to make this thread sleep for
* say sleepTime(10) minutes before it checks the files once again
* because looping continuously causes wastage of CPU cycles.   
Thread.sleep(waitSeconds*1000);
//read list of files
fileNames=fread.list();
if(fileNames.length;=0)
* time is up but there are no file
* in dir1 to copy. Then this program
* goes to sleep for some time and
* checks only at 11:55 hours. That is
* end of the day
continue;
fileSize=new long[fileNames.length];
fileNamesOut=new String[fileNames.length];
//read their sizes
for(i=0;i<fileNames.length;++i)
fileNamesOut<i>=fileNames<i>;
fileNames<i>=dir1+System.getProperty("file.separator";)+fileNames<i>;
fileSize<i>=new File(fileNames<i>).length();
System.out.println(fileNames<i>+" size="+fileSize<i>);
//sorting on basis of file size descending order
long value;
String temp;
for(i=1;i<fileSize.length;++i)
value=fileSize<i>;
temp=fileNames<i>;
for(j=i-1;j>=0 && fileSize[j]<value;--j)
fileSize[j+1]=fileSize[j];
fileNames[j+1]=fileNames[j];
fileSize[j+1]=value;
fileNames[j+1]=temp;
//now copy files to dir2
b=new byte[512];
for(i=0;i<fileNames.length;++i)
System.out.println(fileNames<i>+" size="+fileSize<i>);
for(i=0;i<fileNames.length;++i)
File f=new File(fileNames<i>);
FileInputStream in=new FileInputStream(f);
FileOutputStream out=new FileOutputStream(dir2+System.getProperty("file.separator";)+fileNamesOut<i>);
int len=0;
while(2>1)
if((len=in.read(b))<0)
break;
out.write(b,0,len);
in.close();
//delete files after copying from dir1
f.delete();
out.close();
//put each file after polling interval is over
Thread.sleep(pollingInterval*1000);
catch(Exception e)
e.printStackTrace();
The code runs in infinite loop. You need to run them in command line in DOS environment as you indicated that you OS is WIN XP.  I have a few print statements which I kept for debugging, you can safely remove them and run the codes. This code is independent of the Operating System you are using. Only change is required in values of "dir1","dir2", timings and file count, which I think you can take care easily.
Hope this solves your problem.
regards
Anupam