Java Path Relative getRelative(String basedir, String child)

Description

Given a basedir and a child file, return the relative path to the child.

License

Apache License

Parameter

Parameter	Description
basedir	the basedir.
child	the child path (can be a full path)

Return

the relative path to the child. (NOTE: this path will NOT start with a character)

Declaration

public static String getRelative(String basedir, String child) 

Method Source Code

//package com.java2s;
/*/*from w w w . j  a v a  2 s.c o m*/
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

import java.io.File;

public class Main {
    /**
     * Given a basedir and a child file, return the relative path to the child.
     *
     * @param basedir the basedir.
     * @param file    the file to get the relative path for.
     * @return the relative path to the child. (NOTE: this path will NOT start with a {@link File#separator} character)
     */
    public static String getRelative(String basedir, File file) {
        return getRelative(basedir, file.getAbsolutePath());
    }

    /**
     * Given a basedir and a child file, return the relative path to the child.
     *
     * @param basedir the basedir.
     * @param child   the child path (can be a full path)
     * @return the relative path to the child. (NOTE: this path will NOT start with a {@link File#separator} character)
     */
    public static String getRelative(String basedir, String child) {
        if (basedir.endsWith("/") || basedir.endsWith("\\")) {
            basedir = basedir.substring(0, basedir.length() - 1);
        }

        if (child.startsWith(basedir)) {
            // simple solution.
            return child.substring(basedir.length() + 1);
        }

        String absoluteBasedir = new File(basedir).getAbsolutePath();
        if (child.startsWith(absoluteBasedir)) {
            // resolved basedir solution.
            return child.substring(absoluteBasedir.length() + 1);
        }

        // File is not within basedir.
        throw new IllegalStateException(
                "Unable to obtain relative path of file " + child + ", it is not within basedir " + basedir + ".");
    }
}

Related

1. getRelative(File base, File path)
2. getRelative(File base, File path)
3. getRelativeAncestor(File ancestor, File descendant)
4. getRelativeBaseDirectory(final File processedFile)
5. getRelativeChildDirectory(String parent, String child)
6. getRelativeDirectoryPath(String in_filePath, String in_basePath)