Question

我一直在尝试将数组写入文件。我知道如何将整数或字符串写入文件但是让数组混淆了我。我现在正在使用它：

public static void write (String file, int[]x) throws IOException{
    BufferedWriter outputWriter = null;
    outputWriter = new BufferedWriter(new FileWriter(filename));
    outputWriter.write("hi");// Here I know i cant just write x[0] or anything. Do i need 
                             //to loop in order to write the array?
    outputWriter.newLine();
    outputWriter.flush();  
    outputWriter.close();  



}

Answer 1

您可以使用ObjectOutputStream类将对象写入基础流。

outputStream = new ObjectOutputStream(new FileOutputStream(filename));
outputStream.writeObject(x);

然后阅读Object回来 -

inputStream = new ObjectInputStream(new FileInputStream(filename));
x = (int[])inputStream.readObject()

Answer 2

像其他人说的那样，你可以循环遍历数组并逐个打印出元素。使输出显示为数字而不是＆＃34;字母和符号＆＃34;你看到了，你需要将每个元素转换为字符串。所以你的代码就是这样的：

public static void write (String filename, int[]x) throws IOException{
  BufferedWriter outputWriter = null;
  outputWriter = new BufferedWriter(new FileWriter(filename));
  for (int i = 0; i < x.length; i++) {
    // Maybe:
    outputWriter.write(x[i]+"");
    // Or:
    outputWriter.write(Integer.toString(x[i]);
    outputWriter.newLine();
  }
  outputWriter.flush();  
  outputWriter.close();  
}

如果您只想打印出像[1, 2, 3, ....]这样的数组，可以用这一个衬里替换循环：

outputWriter.write(Arrays.toString(x));

Answer 3

如果你对Apache commons lib

没问题

outputWriter.write(ArrayUtils.join(array, ","));

Answer 4

只需循环遍历数组中的元素。

例如：

for(int i=0; numOfElements > i; i++)
{
outputWriter.write(array[i]);
}
//finish up down here

Answer 5

如果结果是供人阅读并且数组的元素具有正确的toString()定义...

outputString.write(Arrays.toString(array));

Answer 6

private static void saveArrayToFile(String fileName, int[] array) throws IOException {
        Files.write(Paths.get(fileName), Collections.singleton(Arrays.toString(array)), Charset.forName("UTF-8"));
}

如何将数组写入Java文件

6 个答案: