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Java读取输入字符串的方法有多种:标准输入流System.inScanner类BufferedReader类

How to read input string in java

Java 读取输入的字符串

方法

Java 提供多种方法来从用户读取字符串:

  • 标准输入流
  • Scanner 类
  • BufferedReader 类

标准输入流

System.in 字段表示标准输入流。使用 nextLine() 方法可以读取一行文本:

import java.io.InputStreamReader;

public class Main {
    public static void main(String[] args) {
        InputStreamReader reader = new InputStreamReader(System.in);
        String input = reader.readLine();
        System.out.println(input);
    }
}

Scanner 类

Scanner 类提供了更方便的方法来读取输入:

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);
        String input = scanner.nextLine();
        System.out.println(input);
    }
}

Scanner 类还支持读取其他数据类型,比如整数和浮点数。

BufferedReader 类

BufferedReader 类是一种底层读取器,提供了更高级别的功能:

import java.io.BufferedReader;
import java.io.InputStreamReader;

public class Main {
    public static void main(String[] args) {
        BufferedReader reader = new BufferedReader(new InputStreamReader(System.in));
        String input = reader.readLine();
        System.out.println(input);
    }
}

readLine() 方法会读取整行文本,包括换行符。可以使用 trim() 方法删除开头的和结尾的空格。

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