Java Path File Check nio isContained(Path contained, Path container)

Description

Inspired by <a href="http://stackoverflow.com/questions/18227634/check-if-file-is-in-subdirectory" >http://stackoverflow.com/questions/18227634/check-if-file-is-in-subdirectory</a>

License

Open Source License

Parameter

Parameter	Description
contained	The path to be checked. This does not need to exist.
container	The parent directory. This must exist on the filesystem.

Exception

Parameter	Description
IOException	If an error occurs or, potentially, if either path does not exist.

Return

If contained is a subfolder of container, true.

Declaration

public static boolean isContained(Path contained, Path container) throws IOException

Method Source Code

//package com.java2s;
//License from project: Open Source License 

import java.io.IOException;

import java.nio.file.Files;
import java.nio.file.Path;

public class Main {
    /**/*  ww  w.  ja v  a  2 s.  c o m*/
     * Inspired by <a href="http://stackoverflow.com/questions/18227634/check-if-file-is-in-subdirectory"
     * >http://stackoverflow.com/questions/18227634/check-if-file-is-in-subdirectory</a>
     *
     * @param contained The path to be checked. This does not need to exist.
     * @param container The parent directory. This must exist on the filesystem.
     * @return If <code>contained</code> is a subfolder of <code>container</code>, true.
     * @throws IOException If an error occurs or, potentially, if either path does not exist.
     */
    public static boolean isContained(Path contained, Path container) throws IOException {
        Path current = contained.normalize();

        // Iterate up the path to see if we find the container path:
        while (current != null) {
            if (Files.isSameFile(container, current)) {
                return true;
            }
            current = current.getParent();
        }

        // If we didn't find the container path
        // amongst the parents of the contained path,
        // this path is not contained:
        return false;
    }
}