How to find how much disk space is left using Java?

Have a look at the File class documentation. This is one of the new features in 1.6.

These new methods also include:

• public long getTotalSpace()
• public long getFreeSpace()
• public long getUsableSpace()

If you're still using 1.5 then you can use the Apache Commons IO library and its FileSystem class

Use CommonsIO and FilesystemUtils:

https://commons.apache.org/proper/commons-io/javadocs/api-2.5/org/apache/commons/io/FileSystemUtils.html#freeSpaceKb()

e.g.

FileSystemUtils.freeSpaceKb("/"); 

or built into the JDK:

http://java.sun.com/javase/6/docs/api/java/io/File.html#getFreeSpace()

new File("/").getFreeSpace();