这是我的大学任务,这是一个mp3目录。但我不知道为什么它不运行。错误是主方法中有错误。谁能帮忙?此外,如果任何人都可以让我知道如何添加一个'重新排序'功能,他的目录将不胜感激。非常感谢为什么不运行?
import java.util.ArrayList;
import java.util.Scanner;
import java.util.Random;
public class mp3catalogue
{
// An ArrayList for storing the file names of music files.
private ArrayList<String> tracks;
//public mp3catalogue();
public static void main(String[] args) {
}
{
tracks = new ArrayList<String>();
Random randomtrack = new Random();
System.out.println("Music library loaded.");
System.out.println();
}
//Next: File number to be added
public void addNumber(int filename){
int x = 0;
}
{
Scanner in = new Scanner (System.in);
System.out.print("Number of track?");
int x;
int number = x;
while (number <= 1);
String number1 = in.nextLine();
}
//Next: File name to be added
public void addFile(String filename)
{
tracks.add(filename);
Scanner in = new Scanner(System.in);
System.out.print("Name of the track?");
String name = in.nextLine();
}
//Next: Artist to be added
public void addArtist(String filename){
Scanner in1 = new Scanner(System.in);
System.out.print("Track artist?");
Scanner in;
String name1 = in.nextLine();
}
//Next: Duration to be added
public void addDuration(double filename)
{
Scanner in = new Scanner (System.in);
System.out.println("Track duration?");
String name = in.nextLine();
}
// Next: Deleting a track
public void removeFile(int index)
{
if(index >= 0 && index < tracks.size()) {
tracks.remove(index);}
}
// Next: Shuffle the tracks.
public void randomAllTracks(int index)
{
int trackNumber = getNumberOfFiles();
int index1 = Random.nextInt(trackNumber);
if(indexValid(index1))
{
}
}
// Next: Search for a track.
public static int binarySearch (int[] list, int listlength, int searchItem){
int first = 0;
int last = listlength - 1;
int mid;
boolean found = false;
while (first <= last &&!found){
}
return searchItem;
}
private int getNumberOfFiles() {
return 0;
}
private boolean indexValid(int index) {
return false;
}
}
这是什么错误? –
主要是空白的,你必须从中调用一些东西来发生。 – Konstantin
请编辑和格式化您的代码,使其符合Java标准。编码标准使您的代码更易于阅读,并且更易于理解。如果你使用了正确的格式,你可能已经注意到你已经在你的方法之外编写了代码。 –