Glassfish example source code file (SmartFile.java)

This example Glassfish source code file (SmartFile.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - Glassfish tags/keywords

exception, file, hashset, io, linkedlist, list, log, logging, nullpointerexception, nullpointerexception, set, smartfile, smartfile, string, string, stringbuilder, stringbuilder, util

The Glassfish SmartFile.java source code

/*
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 *
 * Copyright (c) 2008-2010 Oracle and/or its affiliates. All rights reserved.
 *
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 * General Public License Version 2 only ("GPL") or the Common Development
 * and Distribution License("CDDL") (collectively, the "License").  You
 * may not use this file except in compliance with the License.  You can
 * obtain a copy of the License at
 * https://glassfish.dev.java.net/public/CDDL+GPL_1_1.html
 * or packager/legal/LICENSE.txt.  See the License for the specific
 * language governing permissions and limitations under the License.
 *
 * When distributing the software, include this License Header Notice in each
 * file and include the License file at packager/legal/LICENSE.txt.
 *
 * GPL Classpath Exception:
 * Oracle designates this particular file as subject to the "Classpath"
 * exception as provided by Oracle in the GPL Version 2 section of the License
 * file that accompanied this code.
 *
 * Modifications:
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package com.sun.enterprise.universal.io;

import java.io.*;
import java.util.*;
import java.util.logging.Level;
import java.util.logging.Logger;

import com.sun.enterprise.util.StringUtils;
import com.sun.enterprise.universal.glassfish.GFLauncherUtils;

/**
 * A class for sanitizing Files.
 * Note that the main reason for this class is that on non-Windows, 
 * getCanonicalXXX and getAbsoluteXXX might point at different files.  
 * If the file is a soft link then the Canonical will be the file that is linked to.
 * The Absolute will be the link file itself.
 * This method will give you the benefits of Canonical -- but will always point
 * at the link file itself. 
 * Windows is horribly complex compared to "everything else".  Windows does not have
 * the symbolic link issue -- so use getCanonicalXXX to do the work on Windows.
 * Windows will return paths with all forward slashes -- no backward slashes unless it
 * is the special Windows network address that starts with "\\"
 * <p>
 * I.e. It is just like getAbsoluteXXX -- but it removes all relative path 
 * elements from the path.
 * @author bnevins
 */
public class SmartFile {

    /**
     * Sanitize a File object -- remove all relative path portions, i.e. dots
     * e.g. "/xxx/yyy/././././../yyy"  --> /xxx/yyy on UNIX, perhaps C:/xxx/yyy on Windows
     * @param f The file to sanitize
     * @return THe sanitized File
     */
    public static File sanitize(File f) {
        SmartFile sf = new SmartFile(f);
        return new File(sf.path);
    }

    /**
     * Sanitize a path -- remove all relative path portions, i.e. dots
     * e.g. "/xxx/yyy/././././../yyy"  --> /xxx/yyy on UNIX, perhaps C:/xxx/yyy on Windows
     * Note that the main reason for this class is that on non-Windows, 
     * getCanonicalXXX and getAbsoluteXXX might point at different files.  
     * If the file is a soft link then the Canonical will be the file that is linked to.
     * The Absolute will be the link file itself.
     * This method will give you the benefits of Canonical -- but will always point
     * at the link file path itself. 
     * @param filename The path to sanitize
     * @return The sanitized path
     */
    public static String sanitize(String filename) {
        SmartFile sf = new SmartFile(filename);
        return sf.path;
    }

    /**
     * Sanitize a "Classpath-like" list of Paths.
     * @param pathsString A string of paths, each separated by File.pathSeparator
     * @return The sanitized paths
     */
    public static String sanitizePaths(String pathsString) {
        if (!ok(pathsString))
            return pathsString;

        try {
            String[] paths = pathsString.split(File.pathSeparator);
            StringBuilder sb = new StringBuilder();
            Set<String> pathsSet = new HashSet();
            List<String> pathsList = new LinkedList();

            for (int i = 0; i < paths.length; i++) {
                String path = paths[i];

                // ignore empty path elements.  E.g. "c:/foo;;;;;;;" should become "C:/foo"
                // not "c:/foo;thisdir;thisdir;thisdir etc"
                if (!ok(path))
                    continue;

                // pathsSet is only here for removing duplicates.  We need the
                // List to maintain the original order!
                path = SmartFile.sanitize(path);

                if (pathsSet.add(path))
                    pathsList.add(path);
            }

            boolean firstElement = true;
            for (String path : pathsList) {
                if (firstElement)
                    firstElement = false;
                else
                    sb.append(File.pathSeparator);

                sb.append(path);
            }
            return sb.toString();
        }
        catch (Exception e) {
            return pathsString;
        }
    }

    private SmartFile(File f) {
        if (f == null)
            throw new NullPointerException();

        convert(f.getAbsolutePath());
    }

    private SmartFile(String s) {
        if (s == null)
            throw new NullPointerException();

        // note that "" is a valid filename
        // IT 7500 get rid of quotes!!!
        s = StringUtils.removeEnclosingQuotes(s);
        convert(new File(s).getAbsolutePath());
    }

    private void convert(String oldPath) {
        if (GFLauncherUtils.isWindows())
            convertWindows(oldPath);
        else
            convertNix(oldPath);
    }

    /*
     * There is no symlink issue with getCanonical vs getAbsolute
     * so we do it the EASY way here...
     */
    private void convertWindows(String oldPath) {
        try {
            path = new File(oldPath).getCanonicalPath();
            if (!path.startsWith("\\")) // network address...
                path = path.replace('\\', '/');
        }
        catch (IOException ex) {
            // what to do?  This has never happened to me and I use File I/O
            //** a lot **
            path = oldPath.replace('\\', '/');
        }
    }

    private void convertNix(String oldPath) {
        // guarantee -- the beginning will not have "." or ".." 
        // (because of getAbsolutePath()...)
        char[] p = oldPath.toCharArray();

        int from, to;
        for (from = 0, to = 0; from < p.length; from++) {
            if (p[from] == '/' &&
                ((from + 3 < p.length &&
                  p[from+1] == '.' && p[from+2] == '.' && p[from+3] == '/') ||
                 (from + 3 == p.length &&
                  p[from+1] == '.' && p[from+2] == '.'))) {
                // remove the previous directory due to /../
                while (to > 0 && p[--to] != '/');
                from += 2;
            }
            else if (p[from] == '/' &&
                    ((from + 2 < p.length &&
                      p[from+1] == '.' && p[from+2] == '/') ||
                     (from + 2 == p.length &&
                      p[from+1] == '.'))) {
                // skip over /./
                from += 1;
            }
            else {
                p[to++] = p[from];
            }
        }
        if (to > 0 && p[to-1] == '/') to -= 1;
        path = new String(p, 0, to);
    }

    private static boolean ok(String s) {
        return s != null && s.length() > 0;
    }

    private String path;
}