我是 Java 新手,现在迷路了。
我有这个代码:
import java.io.BufferedReader;
import java.io.File;
import java.io.FileReader;
/**
*
* @author Darwish
*/
public class M3UReader {
/**
* @param args the command line arguments
*/
public static boolean isValidHeader(String playList)
{
boolean returnValue = false;
BufferedReader br;
try
{
br = new BufferedReader(new FileReader(new File(playList)));
String s = br.readLine(); // declares the variable "s"
if(s.startsWith("#EXTM3U")) { // checks the line for this keyword
returnValue = true; // if its found, return true
}
br.close();
}
catch (Exception e)
{
System.err.println("isValidHeader:: error with file "+ playList + ": " + e.getMessage());
}
return returnValue;
}
public static int getNumberOfTracks(String playList)
{
int numberOfTracks = 0; // sets the default value to zero "0"
try
{
BufferedReader br = new BufferedReader(new FileReader(new File(playList)));
String s;
while((s = br.readLine())!=null) // if "s" first line is not null
{
if(s.startsWith("#")==false) { // if the first line starts with "#" equals to false.
numberOfTracks++; // increments
}
}
br.close();
}
catch (Exception e)
{
numberOfTracks = -1; // chek if the file doesnt exist
System.err.println("could not open/read line from/close filename "+ playList);
}
return numberOfTracks;
}
public static int getTotalMinutes(String playList)
{
// code needed here
}
public static void main(String[] args) {
// TODO code application logic here
String filename = "files\\playlist.m3u"; // finds the file to read (filename <- variable declaration.)
boolean isHeaderValid = M3UReader.isValidHeader(filename); // declares the variabe isHeaderValid and links it with the class isValidHeader
System.out.println(filename + "header tested as "+ isHeaderValid); // outputs the results
if(isHeaderValid)
{
int numOfTracks = M3UReader.getNumberOfTracks(filename);
System.out.println(filename + " has "+ numOfTracks + " tracks ");
}
}
}
在 getTotalMinutes 方法上,我必须找到一种方法来计算从文件中读取的 int 值的总数。该文件具有以下数据:
#EXTM3U
#EXTINF:537,Banco De Gaia - Drippy F:\SortedMusic\Electronic\Banco De Gaia\Big Men Cry\01 Drippy.mp3
#EXTINF:757,Banco De Gaia - Celestine F:\SortedMusic\Electronic\Banco De Gaia\Big Men Cry\02 Celestine.mp3
#EXTINF:565,Banco De Gaia - Drunk As A Monk F:\SortedMusic\Electronic\Banco De Gaia\Big Men Cry\03 Drunk As A Monk.mp3
#EXTINF:369,Banco De Gaia - Big Men Cry F:\SortedMusic\Electronic\Banco De Gaia\Big Men Cry\04 Big Men Cry.mp3
#EXTINF: 后面的数字是音乐的长度,根据上面的数据,以秒为单位。
我不知道在 getTotalMinutes 方法上写什么代码来让程序从文件中读取分钟数,然后计算所有这些分钟数以获得总分钟数。我在网上搜索了如何做到这一点,不幸的是我找不到任何东西。所以任何帮助表示赞赏。