Having a bit of trouble moving objects I've created into an array. So what I actually need to do is create objects than move them into an array. I'm not quite sure what I'm doing wrong.
If you think I should be using a arraylist instead of a array please say so
I made a quick example with less data fields than my actual program but its pretty well the same as my lar开发者_开发问答ger problem. Thank you for your time.
public class Music {
private static String songTitle;
private static double songLength;
private int rating;
public Music(String songTitle, double songLength, int rating) {
// TODO Auto-generated constructor stub
}
public static String getsongTitle()
{
return songTitle;
}
public static double getsongLength()
{
return songLength;
}
public static int rating()
{
return rating();
}
//constructors for music objects
Music song1 = new Music ("song name", 5.32, 10);
Music song2 = new Music ("billy",1.2, 8 );
Music song3 = new Music ("hello", 1.5, 9 );
static //Create array and make posistion 0 = song1
Music[] songDetails = new Music[3];{
songDetails[0] = song1;
}
public static void main(String[] args) {
//print first place in array
System.out.println(songDetails[0]);
}
Edit had a spelling mistake in the code and was missing the word static in the array declaration
Almost everything is OK here ;) There are many ways. Simply access songDetails from nonstatic method (and change Music fields to nonstatic, and implement Music constructor):
public class TryMusic {
Music song1 = new Music("song name", 5.32, 10);
Music song2 = new Music("billy", 1.2, 8);
Music song3 = new Music("hello", 1.5, 9);
//Create array and make posistion 0 = song1
Music[] songDetails;// = new Music[3];
{
//some initializations goes here
//...
//create array when you know how many songs you have
songDetails = new Music[3];
// and now fill the array. Possibly iteration? if no then simply use {} syntax
songDetails[0] = song1;
songDetails[1] = song2;
songDetails[2] = song3;
}
public void go() {
//print first place in array
System.out.println(songDetails[0]);
}
public static void main(String[] args) {
new TryMusic().go();
}
}
You may also want do it like this:
public class TryMusic {
//Create array and make posistion 0 = song1
Music[] songDetails;// = new Music[3];
{
//if you still need initialization block, but don't need field for each song
songDetails = new Music[3];
//possibly iteration? if no then simply use {} syntax instead
songDetails[0] = new Music("song name", 5.32, 10);
songDetails[1] = new Music("billy", 1.2, 8);
songDetails[2] = new Music("hello", 1.5, 9);
}
public void go() {
//print first place in array
System.out.println(songDetails[0]);
}
public static void main(String[] args) {
new TryMusic().go();
}
}
or this (more readable):
public class TryMusic {
//Create array and make posistion 0 = song1
//if simply array is enough
Music[] songDetails = { new Music("song name", 5.32, 10),
new Music("billy", 1.2, 8),
new Music("hello", 1.5, 9)
};
public void go() {
//print first place in array
System.out.println(songDetails[0]);
}
public static void main(String[] args) {
new TryMusic().go();
}
}
or (more flexible):
public class TryMusic {
//Create array and make posistion 0 = song1
List<Music> songDetails = new ArrayList(){{
add(new Music("song name", 5.32, 10));
add(new Music("song name", 5.32, 10));
add(new Music("hello", 1.5, 9));
}};
public void go() {
//print first place in array
System.out.println(songDetails.get(0));
}
public static void main(String[] args) {
new TryMusic().go();
}
}
COMMENT FOR YOUR EDIT: the array was static, but initialization was not static. You missed static keyword before initialization block:
public class TryMusic {
//Create array and make posistion 0 = song1
static Music[] songDetails = new Music[3];
static {
songDetails[0] = new Music("song name", 5.32, 10);
songDetails[1] = new Music("billy", 1.2, 8);
songDetails[2] = new Music("hello", 1.5, 9);
}
public static void main(String[] args) {
System.out.println(songDetails[0]);
}
}
and static version with list:
public class TryMusic {
//Create array and make posistion 0 = song1
static List<Music> songDetails = new ArrayList(){{
add(new Music("song name", 5.32, 10));
add(new Music("song name", 5.32, 10));
add(new Music("hello", 1.5, 9));
}};
public static void main(String[] args) {
System.out.println(songDetails.get(0));
}
}
And oh, I see it now, your Music class is broken too. Use instance fields instead of static and assign values in constructor:
public class Music {
private String songTitle;
private double songLength;
private int rating;
public Music(String songTitle, double songLength, int rating) {
this.songTitle = songTitle;
this.songLength = songLength;
this.rating = rating;
}
public String getsongTitle() {
return songTitle;
}
public double getsongLength() {
return songLength;
}
public int rating() {
return rating;
}
@Override
public String toString() {
return "Music{" + "songTitle=" + songTitle + ", songLength=" + songLength + ", rating=" + rating + '}';
}
}
A very simple way to proceed is:
//constructors for music objects
static Music song1 = new Music ("song name", 5.32, 10);
static Music song2 = new Music ("billy",1.2, 8 );
static Music song3 = new Music ("hello", 1.5, 9 );
static Music[] songDetails = { song1, song2, song3 };
...
public static void main(String[] args) {
System.out.println(songDetails[0].getsongTitle());
}
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