How to I convert an arraylist into an array, and implement this method?

PlayList

import java.io.File; import java.io.FileNotFoundException; import java.text.DecimalFormat; import java.util.ArrayList; import java.util.Scanner; /** * @author */ public class PlayList implements MyTunesPlayListInterface {

private String name;

private Song playing;

/**

* Creates a new array list

*/

private ArrayList songList;

public PlayList(String name){

this.name= name;

this.playing = null;

songList = new ArrayList();

}

/**

* @return returns the name

*/

public String getName(){

return name;

}

/**

* @return returns the song playing

*/

public Song getPlaying(){

return playing;

}

/**

* @param songList name of array list

* @return returns the list of the songs

*/

public ArrayList getsongList(ArrayList songList){

return songList;

}

/**

* @param name sets the name of the song

*/

public void setName(String name){

this.name = name;

}

/**

* @param name adds a song to the play list

*/

public void addSong(Song name){

songList.add(name);

}

/**

* @param i is an integer for the index

* @return removes the song and returns null

*/

public Song removeSong(int i ){

if( i = songList.size()){

return null;

}

return songList.remove(i);

}

/**

* @return returns the number of songs within the play list

*/

public int getNumSongs(){

return songList.size();

}

/**

* @return returns the total play time of the songs

*/

public int getTotalPlayTime(){

int totalPlayT = 0;

for(int s = 0; s

Song s1 = songList.get(s);

s1.getPlayTime();

totalPlayT = totalPlayT + songList.get(s).getPlayTime();

}

return totalPlayT;

}

/**

* @param i is an integer for the index

* @return returns null and gets song for the play list

*/

public Song getSong(int i){

if( i = songList.size()){

return null;

}

return songList.get(i);

}

/**

* @param i is an integer for the index

* @return returns the song that is playing

*/

public void playSong(int i){

if(i >= 0 && i

songList.get(i).play();

playing = songList.get(i);

}else if(i

}else{

Song cSong = this.songList.get(i);

cSong.play();

this.playing = cSong;

}

}

/**

* @return returns various song information, such as the average, longest and shortest play time

*/

public String getInfo(){

String getInfo= "";

if( !songList.isEmpty()){

DecimalFormat df = new DecimalFormat("0.00");

double average = (double)getTotalPlayTime() / songList.size();

Song shortest = songList.get(0);

for(int i = 0; i

Song s2 = songList.get(i);

if(s2.getPlayTime()

shortest = s2;

}

}

Song longest = songList.get(0);

for(int p = 0; p

Song s3 = songList.get(p);

if(s3.getPlayTime() >= longest.getPlayTime()){

longest = s3;

}

}

int totalPlayT = 0;

for(int s = 0; s

Song s1 = songList.get(s);

s1.getPlayTime();

totalPlayT = totalPlayT + songList.get(s).getPlayTime();

}

getInfo += "The average play time is: " + df.format(average)+ " " + "seconds ";

getInfo += "The shortest song is: " + shortest + " ";

getInfo += "The longest song is: " + longest + " ";

getInfo += "Total play time: " + totalPlayT + " " + "seconds ";

} else {

getInfo += "There are no songs. ";

}

return getInfo;

}

/* (non-Javadoc)

* @see java.lang.Object#toString()

*/

public String toString(){

String getInfo = "";

getInfo += "------------------ ";

getInfo += this.getName() + " (" + songList.size() + " songs) ";

getInfo += "------------------ ";

if(!songList.isEmpty()){

for( Song s: songList){

getInfo += "(" + songList.indexOf(s) + ")" + s.toString() + " ";

}

getInfo += "------------------ ";

}else{

getInfo += "There are no songs. ";

getInfo += "------------------ ";

}

return getInfo;

}

@Override

public void loadFromFile(File file) {

songList = new ArrayList();

if(file.exists()) {

try {

Scanner scan = new Scanner(file);

while(scan.hasNextLine()) {

String songName = scan.nextLine().trim();

String artist = scan.nextLine().trim();

String inputTime = scan.nextLine();

int semi = inputTime.indexOf(':');

String min = inputTime.substring(0,semi);

String sec = inputTime.substring(semi+1);

int playTime = (Integer.parseInt(min)*60)+ Integer.parseInt(sec);

String songFile = scan.nextLine().trim();

Song song1 = new Song(songName, artist, playTime, songFile);

System.out.println(song1);

addSong(song1);

}

scan.close();

} catch(FileNotFoundException e) {

System.err.println("Could not read album file: " + e.getMessage());

}

} else {

System.err.println("Album not found:: " + file);

}

}

@Override

public void playSong(Song song) {

// TODO Auto-generated method stub

}

@Override

public void stop() {

// TODO Auto-generated method stub

}

@Override

public Song[] getSongArray() {

// TODO Auto-generated method stub

Song[] copy = new Song[songList.size()];

for(int i =0; i

copy[i]= songList.get(i);

}

return songList.toArray(new Song[0]);

}

@Override

public int moveUp(int index) {

// TODO Auto-generated method stub

return 0;

}

@Override

public int moveDown(int index) {

// TODO Auto-generated method stub

return 0;

}

@Override

public Song[][] getSongSquare() {

// TODO Auto-generated method stub

int songSquareDim = (int)Math.ceil(Math.sqrt(songList.size()));

Song[][] songSquare = new Song [songSquareDim][songSquareDim];

final int MAXVAL = songList.size();

for(int row = 0; row

for(int col = 0; col

songSquare[row][col]= songList.get((row +col) % (MAXVAL +1));

}

}

System.out.println("Songs" + songSquare);

return songSquare;

}

MyTunesGUIInterface

import java.io.File;

/**

* Defines the interface for a MyTunesGUI PlayList class. You may have already

* implemented some of the methods in your previous projects, but are responsible

* for implementing the additional methods outlined below. Make sure to add the

* implements keyword to the top of your PlayList class header.

*

* @author CS121 Instructors

* @version Spring 2017

*/

public interface MyTunesPlayListInterface

{

/**

* Loads songs from specified file into this PlayList. The file must have the

* following format:

*

 
* Song 1 Title
 
* Song 1 Artist
 
* Song 1 Play time (mm:ss)
 
* Song 1 File path
 
* Song 2 Title
 
* Song 2 Artist
 
* Song 2 Play time (mm:ss)
 
* Song 2 File path
 
* etc.
 
* 

* @param file The file to read the songs from.

*/

public void loadFromFile(File file);

/**

* Sets the name of this PlayList.

* @param name The name.

*/

public void setName(String name);

/**

* Returns the name of this PlayList.

* @return The name.

*/

public String getName();

/**

* Returns the song that is currently playing.

* @return The song that is currently playing.

*/

public Song getPlaying();

/**

* Adds the given song to the end of this PlayList.

* @param s The song to add.

*/

public void addSong(Song s);

/**

* Returns the song with the given index from this PlayList, or null

* if the index is invalid.

* @param index The index of the song to retrieve.

* @return The song at index or null if none exists.

*/

public Song getSong(int index);

/**

* Removes the song with the given index from this PlayList, or null

* if the index is invalid.

* @param index The index of the song to remove.

* @return The song at index or null if none exists.

*/

public Song removeSong(int index);

/**

* Returns the number of songs in this PlayList.

* @return The number of songs.

*/

public int getNumSongs();

/**

* Returns the total PlayList of all the songs in this PlayList.

* @return The total play time in seconds.

*/

public int getTotalPlayTime();

/**

* Plays the song at the specified index.

* @param index The index of the song to play.

*/

public void playSong(int index);

/**

* Added for P5.

* Plays the given song (only if the song list contains the song). If it doesn't, then

* it does nothing.

* @param the song to play.

*/

public void playSong(Song song);

/**

* Added for P5.

* Stops the currently playing song (if any) and sets playing song to null.

*/

public void stop();

/**

* Added for P5.

* Returns an array of all the songs in the playlist.

* @return An array of songs.

*/

public Song[] getSongArray();

/**

* Added for P5.

* Moves the song at the given index to the previous index in the list (index - 1). All other elements

* in the list will be shifted. If the index given is zero, it will wrap around and move the song to the

* end of the list.

*

* @param index The index of the song to move.

* @return The new index of the song (after the move). If a song at the given index does not exist,

* or could not be moved for some other reason, returns the original index.

*

*/

// Song[] copy = new Song[songList.size()];

//

// for(int i =0; i

// copy[i]= songList.get(i);

//

// }

public int moveUp(int index);

/**

* Added for P5.

* Moves the song at the given index to the next index in the list (index + 1). All other elements

* in the list will be shifted. If the given index is the last song in the list, it will wrap around

* and move the song to the beginning of the list.

* @param index The index of the song to move.

* @return The new index of the song (after the move). If a song at the given index does not exist,

* or could not be moved for some other reason, returns the original index.

*/

public int moveDown(int index);

/**

* Added for P5.

* Returns a 2 dimensional musical square. The dimension of the square is calculated based on the number of

* songs in the PlayList. If the number of songs in the list are not a square number, then the remaining slots

* are filled starting with the first song.

*

*

* For example, if the PlayList contains 7 songs, the generated array would contain songs in the following

* order.

*

*

*

 
* song0 song1 song2
 
* song3 song4 song5
 
* song6 song0 song1
 
* 

* @return - the 2 dimensional array of songs.

*/

public Song[][] getSongSquare();

}

MyTunesGUIPanel

import java.awt.BorderLayout;

import java.awt.GridLayout;

import java.awt.event.ActionEvent;

import java.awt.event.ActionListener;

import java.io.File;

import java.io.IOException;

import javax.imageio.ImageIO;

import javax.swing.BoxLayout;

import javax.swing.ImageIcon;

import javax.swing.JButton;

import javax.swing.JLabel;

import javax.swing.JList;

import javax.swing.JOptionPane;

import javax.swing.JPanel;

import javax.swing.JScrollPane;

import javax.swing.event.ListSelectionEvent;

import javax.swing.event.ListSelectionListener;

import PhotoAlbumGUIPanel.ControlListener;

import PhotoAlbumGUIPanel.PhotoListListener;

import PhotoAlbumGUIPanel.PhotoSquareListener;

public class MyTunesGUIPanel extends JPanel{

private PlayList list;

private JList songList;

private JLabel songLabel;

private JLabel statLabel;

private JButton nextButton;

private JButton upButton;

private JButton backButton;

private JButton playPauseButton;

private JButton downButton;

private JButton addButton;

private JButton remButton;

private JScrollPane scroll;

private Song[][] songSquare;

private JButton[][] songSquareButtons;

public MyTunesGUIPanel(){

setLayout(new BorderLayout());

JPanel leftPanel = new JPanel();

leftPanel.setLayout(new BoxLayout(leftPanel, BoxLayout.Y_AXIS));

add(leftPanel,BorderLayout.WEST);

list = new PlayList("PlayList");

String filePath = System.getProperty("user.dir")+File.separator + "playlist.txt";

File lFile = new File(filePath);

list.loadFromFile(lFile);

System.out.println(list);

String songStats = list.getNumSongs() + " "+ "Songs " + " " + list.getTotalPlayTime() + " " + " Minutes ";

JPanel statPanel = new JPanel();

statLabel = new JLabel(songStats);

statPanel.add(statLabel);

leftPanel.add(statPanel,BorderLayout.NORTH);

songList = new JList();

songList.setListData(list.getSongArray());

songList.setSelectedIndex(0);

scroll = new JScrollPane(songList, JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED, JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);

leftPanel.add(scroll);

Song current = songList.getSelectedValue();

String currentSong = current.getTitle() + " By " + current.getArtist();

JPanel cPanel = new JPanel();

songLabel = new JLabel(currentSong);

cPanel.add(songLabel);

leftPanel.add(cPanel);

JPanel aPanel = new JPanel();

addButton = new JButton("Add Song");

remButton = new JButton("Remove Song");

aPanel.add(addButton);

aPanel.add(remButton);

leftPanel.add(aPanel);

JPanel lPanel = new JPanel();

upButton = new JButton("Up");

downButton = new JButton("Down");

upButton.addActionListener(new UpDownListener());

downButton.addActionListener(new UpDownListener());

lPanel.add(upButton);

lPanel.add(downButton);

leftPanel.add(lPanel, BorderLayout.WEST);

JPanel sPanel = new JPanel();

backButton = new JButton("

playPauseButton = new JButton("Play");

nextButton = new JButton(">");

backButton.addActionListener(new NextPrevListener());

// playPauseButton.addActionListener(new ControlListener());

nextButton.addActionListener(new NextPrevListener());

sPanel.add(backButton);

sPanel.add(playPauseButton);

sPanel.add(nextButton);

leftPanel.add(sPanel);

displaySong(songList.getSelectedValue());

songSquare = list.getSongSquare();

songSquareButtons = new JButton[songSquare.length][songSquare.length];

JPanel rightPanel = new JPanel();

rightPanel.setLayout(new GridLayout(songSquare.length, songSquare.length));

for (int row = 0; row

for (int col = 0; col

songSquareButtons[row][col] = new JButton();

songSquareButtons[row][col].addActionListener(new SongSquareListener());

rightPanel.add(songSquareButtons[row][col]);

}

}

add(rightPanel,BorderLayout.CENTER);

}

public class SongSquareListener implements ActionListener {

public void actionPerformed(ActionEvent event) {

for (int row = 0; row

for (int col = 0; col

if (event.getSource() == songSquareButtons[row][col]) {

displaySong(songSquare[row][col]);

songList.setSelectedValue(songSquare[row][col], true);

}

}

}

}

}

private class UpDownListener implements ActionListener {

@Override

public void actionPerformed(ActionEvent event) {

int index = songList.getSelectedIndex();

// JOptionPane.showInputDialog("AddSong");

if (event.getSource().equals(upButton)) {

index--;

if (index

index = list.getNumSongs() - 1;

}

songList.setSelectedIndex(index);

} else if (event.getSource().equals(downButton)) {

index++;

if (index >= list.getNumSongs()) {

index = 0;

}

songList.setSelectedIndex(index);

}

songList.setSelectedIndex(index);

}

}

private class NextPrevListener implements ActionListener {

@Override

public void actionPerformed(ActionEvent event) {

int index = songList.getSelectedIndex();

if (event.getSource().equals(backButton)) {

index--;

if (index

index = list.getNumSongs() - 1;

}

songList.setSelectedIndex(index);

} else if (event.getSource().equals(nextButton)) {

index++;

if (index >= list.getNumSongs()) {

index = 0;

}

songList.setSelectedIndex(index);

}

songList.setSelectedIndex(index);

}

}

private void displaySong(Song selectedValue) {

// TODO Auto-generated method stub

}

}

4.4 Step 2: Loading the PlayList The next task is to get the songs loaded into your JList. To do this, you will first need to provide a way to convert your ArrayList of songs into an array of songs (SongC]). 1. Implement the public Songl] getSongArray method provided in the MyTunesPlayListInterface al al ihis rn your I to i the array of s Add the songs from the playlist into your JList (as demonstrated in the PhotoAl- bumGUI lab)