JAVA | 49 - IO 高级应用 | 扫描流

键盘输入

import java.util.Scanner;

public class Main {
public static void main(String[] args) throws Exception{
boolean flag = true;
while (flag){
Scanner scanner = new Scanner(System.in);
if(scanner.hasNextInt()){
System.out.println(Integer.parseInt(scanner.next()));
flag = false;
}else {
System.out.println("Error");
}
}
}
}

文件输入

import java.io.File;
import java.io.FileInputStream;
import java.util.Scanner;

public class Main {
public static void main(String[] args) throws Exception{
File file = new File("/Users/yuzhen/File/testA.txt");
Scanner scanner = new Scanner(new FileInputStream(file));
scanner.useDelimiter("\n"); // 设置读取的分隔符
while (scanner.hasNext()){
System.out.println(scanner.next());
}
}
}