Java Utililty Methods Relative Path Get

int index = p_currentPath.length();
if (!p_currentPath.endsWith(File.separator)) {
    index++;
return p_absolutePath.substring(index);

relativePath = relativePath.trim();
File dir = new File(relativePath).getAbsoluteFile();
File[] jars = dir.listFiles(new FileFilter() {
    public boolean accept(File pathname) {
        if (pathname.isFile()) {
            String fileName = pathname.getName();
            for (String regex : fileNamesRegex) {
                if (fileName.matches(regex)) {
...

File filenameFile = new File(filename);
if (filenameFile.isAbsolute()) {
    return filenameFile;
File dir = peer.isDirectory() ? peer : peer.getParentFile();
return new File(dir, filename).getAbsoluteFile();

if (s.matches("^\\.\\/.*")) {
    File f = new File(s);
    s = f.getAbsolutePath();
    s = s.replaceAll(File.separator + "\\." + File.separator, File.separator);
return s;

String relative = base.toURI().relativize(absolute.toURI()).getPath();
return relative;

return new File(base.toURI().relativize(child.toURI()).getPath());

if (file == null) {
    return null;
if (basedir == null) {
    basedir = new File("").getAbsoluteFile();
} else if (!basedir.isAbsolute()) {
    basedir = basedir.getAbsoluteFile();
String pathname;
String basePath = basedir.getPath();
String filePath = file.getPath();
if (filePath.startsWith(basePath)) {
    if (filePath.length() == basePath.length()) {
        pathname = "";
    } else if (basePath.endsWith(File.separator)) {
        pathname = filePath.substring(basePath.length());
    } else if (filePath.charAt(basePath.length()) == File.separatorChar) {
        pathname = filePath.substring(basePath.length() + 1);
    } else {
        pathname = null;
} else {
    pathname = "";
    for (File current = file; !basedir.equals(current);) {
        String filename = current.getName();
        current = current.getParentFile();
        if (current == null) {
            return null;
        if (pathname.length() > 0) {
            pathname = filename + File.separatorChar + pathname;
        } else {
            pathname = filename;
return pathname;

 example : home = /a/b/c f    = /a/d/e/x.txt s = getRelativePath(home,f) = ../../d/e/x.txt 

List<String> homelist = getPathList(home);
List<String> filelist = getPathList(f);
String s = matchPathLists(homelist, filelist);
return s;

if (!relative.isDirectory()) {
    relative = relative.getParentFile();
String aPath = (path.isDirectory() ? path : path.getParentFile()).getCanonicalPath();
String aRel = relative.getCanonicalPath();
aPath = fixSeparatorChars(aPath);
aRel = fixSeparatorChars(aRel);
String[] aPaths = aPath.split("/");
...

if (root == null)
    throw new IllegalArgumentException("The root file cannot be null.");
if (target == null)
    throw new IllegalArgumentException("The target cannot be null.");
if (!root.isDirectory())
    throw new IllegalArgumentException("The root file must be a directory.");
if (!root.isAbsolute())
    throw new IllegalArgumentException("The root file must be absolute.");
...