import java.io.*;public class IO2File {    public static void main(String[] args) throws IOException {        File f=new File("out.txt");        f.createNewFile();        FileOutputStream fileOutputStream = new FileOutputStream(f);        PrintStream printStream = new PrintStream(fileOutputStream);        System.setOut(printStream);        System.out.println("默认输出到控制台的这一句，输出到了文件 out.txt");    }}