How to check file is a Symbolic Link Using Java

Many time we need to check that a file is symbolic link or actual file using Java.  Here is one simple function from apache commons io library to check symbolic link.

    static boolean isWindows() {
        return File.separatorChar == \'\\\';
    }
    
    public static boolean isSymlink(File file) throws IOException {
        if (file == null) {
            throw new NullPointerException("File must not be null");
        }
        if (isWindows()) {
            return false;
        }
        File fileInCanonicalDir = null;
        if (file.getParent() == null) {
            fileInCanonicalDir = file;
        } else {
            File canonicalDir = file.getParentFile().getCanonicalFile();
            fileInCanonicalDir = new File(canonicalDir, file.getName());
        }
        
        if (fileInCanonicalDir.getCanonicalFile().equals(fileInCanonicalDir.getAbsoluteFile())) {
            return false;
        } else {
            return true;
        }
    }

You can also use apache-commons-io FileUtils class isSymlink function directly if you wan to use that library.