java - java读取文件时内容被删除

Question

我正在编写一个代码来检查一个数字是否是质数，如果是，则将其打印到文件中，但是当我打开InputStream时，它会自动删除文件中的内容! 这是我的代码

import java.util.Scanner;
import java.io.*;
@SuppressWarnings("all")
public class PrimeList {
public static void main(String[]args) throws NumberFormatException, IOException {
    String name = "C:\\Text\\primelist.txt";
    File file = new File(name);
    try {
        OutputStreamWriter wr = new OutputStreamWriter(new FileOutputStream(file));
        BigInteger bi = BigInteger.valueOf(5);
        BigInteger zero = BigInteger.ZERO;
        BigInteger two = BigInteger.valueOf(2);
        while(true) {
            BufferedReader read = new BufferedReader(new InputStreamReader(new FileInputStream(file)));
            while(true) {
                BigInteger prime = BigInteger.valueOf(Long.parseLong(read.readLine()));

谁能告诉我如何解决这个问题？

Answer 1

因为你正在这样做

BufferedReader 读取 = new BufferedReader(new InputStreamReader(new FileInputStream(file)));

每次调用该方法时都会创建新的 FileInputStream(file)