Test URL: api/java_nio/file/FileStore/index.html\#FileStoreTests
JDK Version: JDK 7,8,9

Standalone Code Snippet:

import java.nio.file.*;
import java.io.IOException;

public class NIOTest {
public static void main(String[] args) throws IOException {
for (FileStore store: FileSystems.getDefault().getFileStores()) {
         long total = store.getTotalSpace()/(1024*1024*1024); // Just to convert into Gi
         long avail = store.getUsableSpace()/(1024*1024*1024);
         System.out.format("%-20s %12d %12d%n", store, total, avail);
     }
}
}

Comparing the output of shared location on Mac and Linux:


Code run on mac:

stt-mac-04:bin gtee$ ./java NIOTest

/net/stt-13.ru.oracle.com/export (stt-13.ru.oracle.com:/export) 966Gi 1903Gi
/net/stt-13.ru.oracle.com/export2 (stt-13.ru.oracle.com:/export2) 1147Gi 187Gi

Code run on Linux:

/net/stt-13.ru.oracle.com/export (stt-13.ru.oracle.com:/export) 7110Gi 1903Gi
/net/stt-13.ru.oracle.com/export2 (stt-13.ru.oracle.com:/export2) 7291Gi 187Gi


Output by df -kh :

Filesystem Size Used Avail Capacity iused ifree %iused Mounted on

stt-13.ru.oracle.com:/export2 7.1Ti 6.9Ti 188Gi 98% 58113721 393509647 13% /net/stt-13.ru.oracle.com/export2
stt-13.ru.oracle.com:/export 6.9Ti 5.1Ti 1.9Ti 74% 261224288 3991590226 6% /net/stt-13.ru.oracle.com/export



On Mac, JDK provided wrong information of getTotalSpace and it gives a value less than getUsableSpace.