Java 在字体文件中写入
我需要创建一个方法,该方法给定文件名和一个整数n,然后用该名称写入字符文件,n个随机整数,每行一个。 这是我的代码,我认为它写得正确,但我传递的文件仍然是“空的”,大小为0字节。有人能帮我吗Java 在字体文件中写入,java,file,writing,Java,File,Writing,我需要创建一个方法,该方法给定文件名和一个整数n,然后用该名称写入字符文件,n个随机整数,每行一个。 这是我的代码,我认为它写得正确,但我传递的文件仍然是“空的”,大小为0字节。有人能帮我吗 public static void scriviIntero(String nomeFile, int n) { try (PrintWriter scrivi = new PrintWriter(new FileWriter(nomeFile, true))) { Random r
public static void scriviIntero(String nomeFile, int n) {
try (PrintWriter scrivi = new PrintWriter(new FileWriter(nomeFile, true))) {
Random random = new Random();
for (int i = 0; i < n; i++) {
int nuovo = random.nextInt(99999);
scrivi.println(nuovo);
}
} catch (IOException e) {
System.out.println("Errore di I/O nella funzione scriviIntero nel tentativo di scrivere sul file " + nomeFile);
}
}
publicstaticvoidscrivintero(字符串文件,int-n){
try(PrintWriter scrivi=new PrintWriter(new FileWriter(nomeFile,true))){
随机=新随机();
对于(int i=0;i
您的问题是FileWriter的初始化不正确。查看我放置的true
:
public static void main(String[] args) throws IOException {
appendRandomNumbersToFile("e:/foo.txt", 10);
appendRandomNumbersToFile("e:/foo.txt", 20);
}
public static void appendRandomNumbersToFile(String fileName, int n) throws IOException {
if (n <= 0)
throw new RuntimeException("n should be positive");
try (PrintWriter writer = new PrintWriter(new FileWriter(fileName, true))) {
Random random = new Random();
for (int i = 0; i < n; i++)
writer.println(random.nextInt());
}
}
这应该行得通。您需要检查n>0
,并确保您正在查看要写入的文件。这有什么关系?按照op的方式,它是非附加和自动刷新的。你在哪里做的。
public FileWriter(String fileName, boolean append) {}
public PrintWriter(Writer out, boolean autoFlush) {}