Java I/O - 如何重定向标准错误到文件

import java.io.FileOutputStream;
import java.io.PrintStream;

public class Main {
  public static void main(String[] args) throws Exception {
    System.setErr(new PrintStream(new FileOutputStream("system_err.txt")));

    String nullString = null;
    nullString = nullString.toUpperCase();
  }
}