SyMAT/src/net/apocalypselabs/symat/FileUtils.java

/* 
 * Copyright (c) 2015, Netsyms Technologies
 * All rights reserved.
 * 
 * 
 * CODE LICENSE ==========
 * Redistribution and use in source and binary forms, with or without modification,
 * are permitted provided that the following conditions are met:
 * 
 * 1. Redistributions of source code must retain the above copyright notice, this 
 * list of conditions and the following disclaimer.
 * 
 * 2. Redistributions in binary form must reproduce the above copyright notice, 
 * this list of conditions and the following disclaimer in the documentation and/or
 * other materials provided with the distribution.
 * 
 * 3. Neither the name of the copyright holder nor the names of its contributors 
 * may be used to endorse or promote products derived from this software without 
 * specific prior written permission.
 * 
 * 4. You adhere to the Media License detailed below.  If you do not, this license
 * is automatically revoked and you must purge all copies of the software you
 * possess, in source or binary form.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND 
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED 
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE 
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE LIABLE FOR
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES 
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON 
 * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS 
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * 
 * 
 * MEDIA LICENSE ==========
 * All images and other graphical files ("media") included with this
 * software are copyright (c) 2015 Netsyms Technologies.  You may not distribute
 * the graphics or any program, source code repository, or other digital storage 
 * media containing them without permission from Netsyms Technologies.
 * This ban on distribution only applies to publicly available systems.
 * A password-protected network file share, USB drive, or other storage scheme that
 * cannot be easily accessed by the public is generally allowed.  If in doubt,
 * contact Netsyms Technologies.  If Netsyms Technologies allows or denies
 * you permission, that decision is considered final and binding.
 * 
 * You may only use the media for personal, 
 * non-commercial, non-educational use unless: 
 * 1, You have paid for the software and media via the SyMAT website,
 * or 2, you are using it as part of the 15-day trial period.  
 * Other uses are prohibited without permission.
 * If any part of this license is deemed unenforcable, the remainder 
 * of the license remains in full effect.
 */
package net.apocalypselabs.symat;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.PrintStream;
import java.net.MalformedURLException;
import java.net.URL;
import java.nio.charset.StandardCharsets;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.util.Scanner;
import javax.swing.JFileChooser;
import javax.swing.filechooser.FileNameExtensionFilter;

/**
 * File Utilities.
 *
 * @author Skylar
 */
public class FileUtils {

    /**
     * Read a UTF-8 text file.
     *
     * @param path Where is the file?
     * @return The file contents.
     * @throws IOException
     */
    public static String readFile(String path)
            throws IOException {
        byte[] encoded = Files.readAllBytes(Paths.get(path));
        return new String(encoded, StandardCharsets.UTF_8);
    }

    /**
     * Returns the selected file from a JFileChooser, including the extension
     * from the file filter.
     *
     * Credit to http://stackoverflow.com/users/964243/boann
     *
     * @param c The JFileChooser to extract from.
     * @return duh.
     */
    public static File getFileWithExtension(JFileChooser c) {
        File file = c.getSelectedFile();
        if (c.getFileFilter() instanceof FileNameExtensionFilter) {
            String[] exts = ((FileNameExtensionFilter) c.getFileFilter()).getExtensions();
            String nameLower = file.getName().toLowerCase();
            for (String ext : exts) { // check if it already has a valid extension
                if (nameLower.endsWith('.' + ext.toLowerCase())) {
                    return file; // if yes, return as-is
                }
            }
            // if not, append the first extension from the selected filter
            file = new File(file.toString() + '.' + exts[0]);
        }
        return file;
    }

    /**
     *
     * @param content
     * @param path
     * @param addToRecent
     * @throws IOException
     */
    public static void saveFile(String content, String path, boolean addToRecent)
            throws IOException {
        try (PrintStream out = new PrintStream(new FileOutputStream(path))) {
            out.print(content);
        }
        if (addToRecent) {
            Main.addRecentFile((new File(path)).getAbsolutePath());
        }
    }

    /**
     * Get an MD5 hash.
     *
     * http://stackoverflow.com/a/6565597/2534036
     *
     * @param md5 the text to hash.
     * @return
     */
    public static String MD5(String md5) {
        try {
            java.security.MessageDigest md
                    = java.security.MessageDigest.getInstance("MD5");
            byte[] array = md.digest(md5.getBytes());
            StringBuilder sb = new StringBuilder();
            for (int i = 0; i < array.length; ++i) {
                sb.append(Integer.toHexString((array[i] & 0xFF) | 0x100).substring(1, 3));
            }
            return sb.toString();
        } catch (java.security.NoSuchAlgorithmException e) {
        }
        return null;
    }

    /**
     *
     * @param url
     * @return
     * @throws MalformedURLException
     * @throws IOException
     */
    public static String getUrl(String url) throws MalformedURLException, IOException {
        String out;
        try (Scanner sc = new Scanner(new URL(url).openStream(), "UTF-8")) {
            out = sc.useDelimiter("\\A").next();
        }
        return out;
    }
}