How to Check Free Disk Space in Java

For those who manage file systems and storage in Java applications, monitoring disk space is crucial. Java provides straightforward ways to check free disk space, ensuring that applications handle storage efficiently and avoid issues related to insufficient space. This article will walk you through how to check free disk space in Java, complete with the necessary code snippets.

How to Check Free Disk Space in Java

import java.io.File;

public class DiskSpaceChecker {
    public static void main(String[] args) {
        // Check primary disk
        File diskPartition = new File("/");
        long freeSpace = diskPartition.getFreeSpace();
        double freeSpaceGB = freeSpace / (1024.0 * 1024.0 * 1024.0);
        System.out.println("Free disk space (GB): " + freeSpaceGB);

        // Check total and usable space
        long totalSpace = diskPartition.getTotalSpace();
        long usableSpace = diskPartition.getUsableSpace();

        // Check multiple partitions
        File[] roots = File.listRoots();
        for (File root : roots) {
            System.out.println("Root: " + root.getAbsolutePath());
            System.out.println("Free space (GB): " + root.getFreeSpace() / (1024.0 * 1024.0 * 1024.0));
        }
    }
}

 

•  A File object is created to represent the disk partition. For primary disk checks, we use new File(“/”).
• The getFreeSpace() method fetches free space in bytes. It’s converted to Gigabytes (GB) for readability.
• getTotalSpace() gives the total space of the partition, while getUsableSpace() provides the space available to the JVM.
• By using File.listRoots(), we can iterate over different roots (or partitions) in the file system, checking each partition’s free space.

 

Also Read: How to iterate Java HashMap

Conclusion

Checking disk space in Java is a breeze thanks to the straightforward methods provided by the java.io.File class. Whether you’re dealing with a single partition or multiple ones, these methods can be seamlessly integrated into your Java applications for effective storage management and monitoring.