我在更改文件中的一行時遇到問題,此代碼的用途是將文件的第一個編號更改爲自身+ 1.由於某些原因,代碼不會「噸似乎是在運作,任何幫助將不勝感激!更改文件中的第一行
public static void changenumber(String fileName)
{
ArrayList<String> list = new ArrayList<String>();
File temp = new File(fileName);
Scanner sc;
try {
sc = new Scanner(temp);
while (sc.hasNextLine())
{
list.add(sc.nextLine());
}
sc.close();
}
catch (FileNotFoundException e)
{
e.printStackTrace();
}
String first = list.get(0);
int i = Integer.parseInt(first);
i = i+1;
first = Integer.toString(i);
list.set(0, first);
writenumber(list,fileName);
}
public static void writenumber(ArrayList<String> list, String fileName)
{
PrintWriter write;
try {
write = new PrintWriter(new FileWriter(fileName, true));
for(int i = 0; i<list.size();i++)
{
write.append(list.get(i));
}
}
catch(IOException err)
{
err.printStackTrace();
}
}
您可以嘗試沖洗PrintWriter – jrtapsell