package app.musicplayer.util;
import java.io.File;
import java.io.FileInputStream;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.time.Duration;
import java.time.LocalDateTime;
import java.util.ArrayList;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.stream.XMLInputFactory;
import javax.xml.stream.XMLStreamReader;
import javax.xml.transform.OutputKeys;
import javax.xml.transform.Transformer;
import javax.xml.transform.TransformerFactory;
import javax.xml.transform.dom.DOMSource;
import javax.xml.transform.stream.StreamResult;
import javax.xml.xpath.XPath;
import javax.xml.xpath.XPathConstants;
import javax.xml.xpath.XPathExpression;
import javax.xml.xpath.XPathFactory;
import org.jaudiotagger.audio.AudioFile;
import org.jaudiotagger.audio.AudioFileIO;
import org.jaudiotagger.audio.AudioHeader;
import org.jaudiotagger.tag.FieldKey;
import org.jaudiotagger.tag.Tag;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.w3c.dom.Node;
import org.w3c.dom.NodeList;
import app.musicplayer.MusicPlayer;
import app.musicplayer.model.Library;
import app.musicplayer.model.Song;
public class XMLEditor {
private static String musicDirectory;
// Initializes array lists to store the file names of the songs in the xml file.
// This array lists will be checked to determine if a song has been added or deleted from the music directory.
private static ArrayList<String> xmlSongsFileNames = new ArrayList<>();
// Stores the file paths of the xml songs.
// This is important if a song has to be removed from the xml file as it is used to find the node to remove.
private static ArrayList<String> xmlSongsFilePaths = new ArrayList<>();
// Initializes array lists to store the filenames of the songs in the music directory.
// This array lists will be checked to determine if a song has been added or deleted from the music directory.
private static ArrayList<String> musicDirFileNames = new ArrayList<>();
// Stores files in the music directory.
// This is important if a song has to be added to the xml file and it is used to find the file to add.
private static ArrayList<File> musicDirFiles = new ArrayList<>();
// Initializes array list with song files of songs to be added to library.xml
private static ArrayList<File> songFilesToAdd = new ArrayList<>();
// Initializes array list with song paths of songs to be deleted from library.xml
private static ArrayList<String> songPathsToDelete = new ArrayList<>();
private static ArrayList<Song> songsToAdd = new ArrayList<>();
// Initializes booleans used to determine how the library.xml file needs to be edited.
private static boolean addSongs;
private static boolean deleteSongs;
public static ArrayList<Song> getNewSongs() { return songsToAdd; }
public static void setMusicDirectory(Path musicDirectoryPath) {
musicDirectory = musicDirectoryPath.toString();
}
public static void addDeleteChecker() {
// Finds the file name of the songs in the library xml file and
// stores them in the xmlSongsFileNames array list.
xmlSongsFilePathFinder();
// Finds the song titles in the music directory and stores them in the librarySongs array list.
musicDirFileFinder(new File(musicDirectory));
// Initializes a counter variable to index the musicDirFiles array to get the file
// corresponding to the song that needs to be added to the xml file.
int i = 0;
// Loops through musicDirFiles and checks if the song file names are in the library.xml file.
// If not, then the song needs to be ADDED.
for (String songFileName : musicDirFileNames) {
// If the song file name is not in the xmlSongsFilenames,
// then it was added to the music directory and needs to be added to the xml file.
if (!xmlSongsFileNames.contains(songFileName)) {
// Adds the song file that needs to be added to the array list in XMLEditor.
songFilesToAdd.add(musicDirFiles.get(i));
addSongs = true;
}
i++;
}
// Initializes a counter variable to index the xmlSongsFilePaths array to get the
// file path of the songs that need to be removed from the xml file.
int j = 0;
// Loops through xmlSongsFileNames and checks if all the xml songs are in the music directory.
// If one of the songs in the xml file is not in the music directory, then it was DELETED.
for (String songFileName : xmlSongsFileNames) {
// If the songFileName is not in the musicDirFileNames,
// then it was deleted from the music directory and needs to be deleted from the xml file.
if (!musicDirFileNames.contains(songFileName)) {
// Adds the songs that needs to be deleted to the array list in XMLEditor.
songPathsToDelete.add(xmlSongsFilePaths.get(j));
deleteSongs = true;
}
j++;
}
// If a song needs to be added to the xml file.
if (addSongs) {
// Adds the new song to the xml file.
addSongToXML();
}
// If a song needs to be deleted from the xml file.
if (deleteSongs) {
// Deletes song from library xml file.
deleteSongFromXML();
}
}
private static void xmlSongsFilePathFinder() {
try {
// Creates reader for xml file.
XMLInputFactory factory = XMLInputFactory.newInstance();
factory.setProperty("javax.xml.stream.isCoalescing", true);
FileInputStream is = new FileInputStream(new File(Resources.JAR + "library.xml"));
XMLStreamReader reader = factory.createXMLStreamReader(is, "UTF-8");
String element = null;
String songLocation;
// Loops through xml file looking for song titles.
// Stores the song title in the xmlSongsFileNames array list.
while(reader.hasNext()) {
reader.next();
if (reader.isWhiteSpace()) {
continue;
} else if (reader.isStartElement()) {
element = reader.getName().getLocalPart();
} else if (reader.isCharacters() && element.equals("location")) {
// Retrieves the song location and adds it to the corresponding array list.
songLocation = reader.getText();
xmlSongsFilePaths.add(songLocation);
// Retrieves the file name from the file path and adds it to the xmlSongsFileNames array list.
int i = songLocation.lastIndexOf("\\");
String songFileName = songLocation.substring(i + 1, songLocation.length());
xmlSongsFileNames.add(songFileName);
}
}
// Closes xml reader.
reader.close();
} catch (Exception e) {
e.printStackTrace();
}
}
private static void musicDirFileFinder(File musicDirectoryFile) {
// Lists all the files in the music directory and stores them in an array.
File[] files = musicDirectoryFile.listFiles();
// Loops through the files.
for (File file : files) {
if (file.isFile() && Library.isSupportedFileType(file.getName())) {
// Adds the file to the musicDirFiles array list.
musicDirFiles.add(file);
// Adds the file name to the musicDirFileNames array list.
musicDirFileNames.add(file.getName());
} else if (file.isDirectory()) {
musicDirFileFinder(file);
}
}
}
private static void addSongToXML() {
// Initializes the array list with song objects to add to the xml file.
createNewSongObject();
if (songsToAdd.size() == 0) {
return;
}
try {
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
Document doc = docBuilder.parse(Resources.JAR + "library.xml");
XPathFactory xPathfactory = XPathFactory.newInstance();
XPath xpath = xPathfactory.newXPath();
// Creates node to add songs.
XPathExpression expr = xpath.compile("/library/songs");
Node songsNode = ((NodeList) expr.evaluate(doc, XPathConstants.NODESET)).item(0);
// Loops through the songs in the new song array list and adds them to the xml file.
for (Song song : songsToAdd) {
// Creates a new song element and its sub elements.
Element newSong = doc.createElement("song");
Element newSongId = doc.createElement("id");
Element newSongTitle = doc.createElement("title");
Element newSongArtist = doc.createElement("artist");
Element newSongAlbum = doc.createElement("album");
Element newSongLength = doc.createElement("length");
Element newSongTrackNumber = doc.createElement("trackNumber");
Element newSongDiscNumber = doc.createElement("discNumber");
Element newSongPlayCount = doc.createElement("playCount");
Element newSongPlayDate = doc.createElement("playDate");
Element newSongLocation = doc.createElement("location");
// Saves the new song data.
newSongId.setTextContent(Integer.toString(song.getId()));
newSongTitle.setTextContent(song.getTitle());
newSongArtist.setTextContent(song.getArtist());
newSongAlbum.setTextContent(song.getAlbum());
newSongLength.setTextContent(Long.toString(song.getLengthInSeconds()));
newSongTrackNumber.setTextContent(Integer.toString(song.getTrackNumber()));
newSongDiscNumber.setTextContent(Integer.toString(song.getDiscNumber()));
newSongPlayCount.setTextContent(Integer.toString(song.getPlayCount()));
newSongPlayDate.setTextContent(song.getPlayDate().toString());
newSongLocation.setTextContent(song.getLocation());
// Adds the new song to the xml file.
songsNode.appendChild(newSong);
// Adds the new song data to the new song.
newSong.appendChild(newSongId);
newSong.appendChild(newSongTitle);
newSong.appendChild(newSongArtist);
newSong.appendChild(newSongAlbum);
newSong.appendChild(newSongLength);
newSong.appendChild(newSongTrackNumber);
newSong.appendChild(newSongDiscNumber);
newSong.appendChild(newSongPlayCount);
newSong.appendChild(newSongPlayDate);
newSong.appendChild(newSongLocation);
}
// Calculates the new xml file number, taking into account the new songs.
int newXMLFileNum = MusicPlayer.getXMLFileNum() + songFilesToAdd.size();
// Creates node to update xml file number.
expr = xpath.compile("/library/musicLibrary/fileNum");
Node fileNum = ((NodeList) expr.evaluate(doc, XPathConstants.NODESET)).item(0);
// Updates the fileNum field in the xml file.
fileNum.setTextContent(Integer.toString(newXMLFileNum));
// Updates the xmlFileNum in MusicPlayer.
MusicPlayer.setXMLFileNum(newXMLFileNum);
// Gets the new last id assigned after adding all the new songs.
int newLastIdAssigned = songsToAdd.get(songsToAdd.size() - 1).getId();
// Creates node to update xml last id assigned.
expr = xpath.compile("/library/musicLibrary/lastId");
Node lastId = ((NodeList) expr.evaluate(doc, XPathConstants.NODESET)).item(0);
// Updates the last id in the xml file.
lastId.setTextContent(Integer.toString(newLastIdAssigned));
// Updates the lastId in MusicPlayer.
MusicPlayer.setLastIdAssigned(newLastIdAssigned);
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
DOMSource source = new DOMSource(doc);
File xmlFile = new File(Resources.JAR + "library.xml");
StreamResult result = new StreamResult(xmlFile);
transformer.transform(source, result);
} catch (Exception ex) {
ex.printStackTrace();
}
}
private static void createNewSongObject() {
// Searches the xml file to get the last id assigned.
int lastIdAssigned = xmlLastIdAssignedFinder();
// Loops through each song file that needs to be added and creates a song object for each.
// Each song object is added to an array list and returned so that they can be added to the xml file.
for (File songFile : songFilesToAdd) {
try {
AudioFile audioFile = AudioFileIO.read(songFile);
Tag tag = audioFile.getTag();
AudioHeader header = audioFile.getAudioHeader();
// Gets song properties.
int id = ++lastIdAssigned;
String title = tag.getFirst(FieldKey.TITLE);
// Gets the artist, empty string assigned if song has no artist.
String artistTitle = tag.getFirst(FieldKey.ALBUM_ARTIST);
if (artistTitle == null || artistTitle.equals("") || artistTitle.equals("null")) {
artistTitle = tag.getFirst(FieldKey.ARTIST);
}
String artist = (artistTitle == null || artistTitle.equals("") || artistTitle.equals("null")) ? "" : artistTitle;
String album = tag.getFirst(FieldKey.ALBUM);
// Gets the track length (as an int), converts to long and saves it as a duration object.
Duration length = Duration.ofSeconds((long) header.getTrackLength());
// Gets the track number and converts to an int. Assigns 0 if a track number is null.
String track = tag.getFirst(FieldKey.TRACK);
int trackNumber = Integer.parseInt((track == null || track.equals("") || track.equals("null")) ? "0" : track);
// Gets disc number and converts to int. Assigns 0 if the disc number is null.
String disc = tag.getFirst(FieldKey.DISC_NO);
int discNumber = Integer.parseInt((disc == null || disc.equals("") || disc.equals("null")) ? "0" : disc);
int playCount = 0;
LocalDateTime playDate = LocalDateTime.now();
String location = Paths.get(songFile.getAbsolutePath()).toString();
// Creates a new song object for the added song and adds it to the newSongs array list.
Song newSong = new Song(id, title, artist, album, length, trackNumber, discNumber, playCount, playDate, location);
// Adds the new song to the songsToAdd array list.
songsToAdd.add(newSong);
} catch (Exception ex) {
ex.printStackTrace();
}
}
// Updates the lastIdAssigned in MusicPlayer to account for the new songs.
MusicPlayer.setLastIdAssigned(lastIdAssigned);
}
private static int xmlLastIdAssignedFinder() {
try {
// Creates reader for xml file.
XMLInputFactory factory = XMLInputFactory.newInstance();
factory.setProperty("javax.xml.stream.isCoalescing", true);
FileInputStream is = new FileInputStream(new File(Resources.JAR + "library.xml"));
XMLStreamReader reader = factory.createXMLStreamReader(is, "UTF-8");
String element = null;
String lastId = null;
// Loops through xml file looking for the music directory file path.
while(reader.hasNext()) {
reader.next();
if (reader.isWhiteSpace()) {
continue;
} else if (reader.isStartElement()) {
element = reader.getName().getLocalPart();
} else if (reader.isCharacters() && element.equals("lastId")) {
lastId = reader.getText();
break;
}
}
// Closes xml reader.
reader.close();
// Converts the file number to an int and returns the value.
return Integer.parseInt(lastId);
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
private static void deleteSongFromXML() {
// Gets the currentXMLFileNum.
int currentXMLFileNum = MusicPlayer.getXMLFileNum();
try {
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
Document doc = docBuilder.parse(Resources.JAR + "library.xml");
XPathFactory xPathfactory = XPathFactory.newInstance();
XPath xpath = xPathfactory.newXPath();
// Retrieves the last id assigned to a song from the xml file.
int xmlLastIdAssigned = xmlLastIdAssignedFinder();
// Finds the song node corresponding to the last assigned id.
XPathExpression expr = xpath.compile("/library/songs/song[id/text() = \"" + xmlLastIdAssigned + "\"]");
Node lastSongNode = ((NodeList) expr.evaluate(doc, XPathConstants.NODESET)).item(0);
// Loops through the songPathsToDelete array list and removes the nodes from the xml file.
Node deleteSongNode = null;
for (String songFilePath : songPathsToDelete) {
// Finds the node with the song title marked for removal.
expr = xpath.compile("/library/songs/song[location/text() = \"" + songFilePath + "\"]");
deleteSongNode = ((NodeList) expr.evaluate(doc, XPathConstants.NODESET)).item(0);
// Removes the node corresponding to the title of the song.
deleteSongNode.getParentNode().removeChild(deleteSongNode);
// Decreases the counter for the number of files in the xml file.
currentXMLFileNum--;
}
// If the last node to be deleted was the last song node,
// then the new last assigned id is found and updated in the MusicPlayer and xml file.
if (deleteSongNode == lastSongNode) {
int newLastIdAssigned = xmlNewLastIdAssignedFinder();
// Creates node to update xml last id assigned.
expr = xpath.compile("/library/musicLibrary/lastId");
Node lastId = ((NodeList) expr.evaluate(doc, XPathConstants.NODESET)).item(0);
// Updates the lastId in MusicPlayer and in the xml file.
MusicPlayer.setLastIdAssigned(newLastIdAssigned);
lastId.setTextContent(Integer.toString(newLastIdAssigned));
}
// Creates node to update xml file number.
XPathExpression fileNumExpr = xpath.compile("/library/musicLibrary/fileNum");
Node fileNum = ((NodeList) fileNumExpr.evaluate(doc, XPathConstants.NODESET)).item(0);
// Updates the fileNum in MusicPlayer and in the xml file.
MusicPlayer.setXMLFileNum(currentXMLFileNum);
fileNum.setTextContent(Integer.toString(currentXMLFileNum));
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
DOMSource source = new DOMSource(doc);
File xmlFile = new File(Resources.JAR + "library.xml");
StreamResult result = new StreamResult(xmlFile);
transformer.transform(source, result);
} catch (Exception ex) {
ex.printStackTrace();
}
}
private static int xmlNewLastIdAssignedFinder() {
try {
// Creates reader for xml file.
XMLInputFactory factory = XMLInputFactory.newInstance();
factory.setProperty("javax.xml.stream.isCoalescing", true);
FileInputStream is = new FileInputStream(new File(Resources.JAR + "library.xml"));
XMLStreamReader reader = factory.createXMLStreamReader(is, "UTF-8");
String element = null;
String location;
String currentSongId = null;
String xmlNewLastIdAssigned = null;
// Loops through xml file looking for the music directory file path.
while(reader.hasNext()) {
reader.next();
if (reader.isWhiteSpace()) {
continue;
} else if (reader.isStartElement()) {
element = reader.getName().getLocalPart();
} else if (reader.isCharacters() && element.equals("id")) {
currentSongId = reader.getText();
} else if (reader.isCharacters() && element.equals("location")) {
location = reader.getText();
// If the current location is does not correspond to one of the files to be deleted,
// then the current id is assigned as the newLastIdAssigned.
if (!songPathsToDelete.contains(location)) {
xmlNewLastIdAssigned = currentSongId;
}
} else if (reader.isEndElement() && reader.getName().getLocalPart().equals("songs")) {
break;
}
}
// Closes xml reader.
reader.close();
// Converts the file number to an int and returns the value.
return Integer.parseInt(xmlNewLastIdAssigned);
} catch (Exception e) {
e.printStackTrace();
return 0;
}
}
public static void deleteSongFromPlaylist(int selectedPlayListId, int selectedSongId) {
try {
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
Document doc = docBuilder.parse(Resources.JAR + "library.xml");
XPathFactory xPathfactory = XPathFactory.newInstance();
XPath xpath = xPathfactory.newXPath();
// Finds the node with the song id for the selected song in the selected play list for removal.
String query = "/library/playlists/playlist[@id='" + selectedPlayListId + "']/songId[text() = '" + selectedSongId + "']";
XPathExpression expr = xpath.compile(query);
Node deleteSongNode = (Node) expr.evaluate(doc, XPathConstants.NODE);
// Removes the node corresponding to the selected song.
deleteSongNode.getParentNode().removeChild(deleteSongNode);
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
DOMSource source = new DOMSource(doc);
File xmlFile = new File(Resources.JAR + "library.xml");
StreamResult result = new StreamResult(xmlFile);
transformer.transform(source, result);
} catch (Exception ex) {
ex.printStackTrace();
}
}
public static void deletePlaylistFromXML(int selectedPlayListId) {
try {
DocumentBuilderFactory docFactory = DocumentBuilderFactory.newInstance();
DocumentBuilder docBuilder = docFactory.newDocumentBuilder();
Document doc = docBuilder.parse(Resources.JAR + "library.xml");
XPathFactory xPathfactory = XPathFactory.newInstance();
XPath xpath = xPathfactory.newXPath();
// Finds the node with the play list id for removal.
String query = "/library/playlists/playlist[@id='" + selectedPlayListId + "']";
XPathExpression expr = xpath.compile(query);
Node deleteplaylistNode = (Node) expr.evaluate(doc, XPathConstants.NODE);
// Removes the node corresponding to the selected song.
deleteplaylistNode.getParentNode().removeChild(deleteplaylistNode);
TransformerFactory transformerFactory = TransformerFactory.newInstance();
Transformer transformer = transformerFactory.newTransformer();
transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "4");
transformer.setOutputProperty(OutputKeys.INDENT, "yes");
DOMSource source = new DOMSource(doc);
File xmlFile = new File(Resources.JAR + "library.xml");
StreamResult result = new StreamResult(xmlFile);
transformer.transform(source, result);
} catch (Exception ex) {
ex.printStackTrace();
}
}
}
