【java】扫描流Scanner接收输入示例

多用Scanner少用InputStream

多用BufferedReader少用Reader

多用PrintStream少用OutputStream

多用PrintWriter少用Writer

 package Scanner;

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

 public class TestScanner {
     public static void main(String[] args) throws FileNotFoundException {
         /*
         Scanner scanner = new Scanner(System.in);
         System.out.println("请输入一个整数：");
         int i = scanner.nextInt();
         System.out.println(i);
         */

         /*
         System.out.println("请输入日期：");//正则匹配
         if (scanner.hasNext("\\d{4}-\\d{2}-\\d{2}"))
             System.out.println(scanner.next());
         else
             System.out.println("输入的不是日期时间。");
         scanner.close();
         */

         Scanner scan=new Scanner(new FileInputStream(new File("D:"+File.separator+"test.txt")));
         scan.useDelimiter("\n");
         while(scan.hasNext())
             System.out.println(scan.next());
         scan.close();
     }
 }