【转】java键盘输入

 初学者学Java时,有时就要接收从键盘输入。大家很容易想到C语言中的scanf()和C++中的cin().可Java中用什么呢?去网上一查好多人说用System.in误导了好多人,包括曾经的我,还有人说下一个插件安装下。本人认为,实现它其实最简单的莫属一个类,Java本身就提供的,这个类就是Scanner.先举个例子如下:

  import java.util.Scanner;

  /**

  * 测试从键盘读取用户的输入,关键类为Scanner

  * @author Administrator

  *

  */

  public class TestInput {

  public static void main(String[] args) {

  Scanner s = new Scanner(System.in);

  System.out.println("请输入你的姓名:");

  String name = s.nextLine();

  System.out.println("请输入你的年龄:");

  int age = s.nextInt();

  System.out.println("请输入你的工资:");

  float salary = s.nextFloat();

  System.out.println("你的信息如下:");

  System.out.println("姓名:"+name+"\n"+"年龄:"+age+"\n"+"工资:"+salary);

  }

  }

  说明:Scanner的对象的方法nextLine()接收字符和字符串类型的输入;nextInt()接收int类型的;nextFloat()接收float类型的,相信后面的就不用一一列举了吧。

  方法2:

  BufferedReader reader=new BufferedReader(new InputStreamReader(System.in));

  System.out.print("Please input a number:");

  String str=reader.readLine();  //获取字符串

  System.out.println("The number you input is:"+str);

  或

  InputStreamReader reader = new InputStreamReader(System.in);

  BufferedReader input = new BufferedReader(reader);

  System.out.print("Enter your age: ");

  String text = input.readLine();

  int age = new Integer(text).intValue();

  System.out.println("You are " + age + " years old, now,");

  int year = 2003 - age;

  System.out.println("so you were probably born in " + year);

  需要抛出io异常。

  import java.io.*;

  - @5 n0 _4 H: c( y: Hclass JavaIO_02N {' U- \9 P1 S, C2 m- R3 p& t

  public static void main(String param[])

  # u   P+ ]+ a2 L6 O! V {: B7 A6 r3 ^   [4 ~

  String nn1="";//定义一个String整型对象nn1: b5 T) n6 E9 f4 @9 p

  BufferedReader distream = new BufferedReader(new InputStreamReader(System.in));

  , p1 J   D/ B, @1 L" q6 P' a     System.out.println("键入一个整数");   r& m/ H2 s' Q   h" T( |+ j

  nn1=distream.readLine();//进行输入,并把输入的数存入nn1中/ l, u4 y3 e5 R   \

  ) J+ D7 n$ u; z% v3 Z7 g# S* w0 l     int n1=Integer.parseInt(nn1);( z4 l# |( L/ q

  if(n1%2==0)

  . C6 b9 U$ D* F( y! K System.out.println(n1+"是一个偶数");

  3 ?! ^" c% C9 ], i- G9 L9 }/ b        else( u- G, Z( Z* {   V# _; _0 O

  System.out.println(n1+"是一个奇数"); 2 _; b) N, Q2 \4 W9 D: y$ t! E5 ~# J

  }% c! z' y( d6 d/ v# {. _7 Q

  }

  1 F: w6 M1 H) |8 j) O: e' C4 e

  & v" }5 S9 }& Y& l8 B

  " f9 G8 K, H+ A6 P% ajava不可能出现语句在任何方法,类之外的

  /* * Created on 2005-4-5

  * * TODO To change the template for this generated file go to

  * Window - Preferences - Java - Code Style - Code Templates

  */

  import java.io.BufferedReader;

  import java.io.IOException;

  import java.io.InputStreamReader;

  /**

  * @author Zhangql

  *

  * TODO To change the template for this generated type comment go to

  * Window - Preferences - Java - Code Style - Code Templates

  */

  public class EnterConsole

  {

  public static void main(String[] args) throws IOException

  {

  EnterConsole enterConsole = new EnterConsole();

  enterConsole.printConsoleChar();

  }

  /**

  * 从控制对接收一行字符串,然后输出到控制台

  * @throws IOException

  */

  public void printConsoleLine() throws IOException

  {

  BufferedReader br = new BufferedReader(new InputStreamReader(System.in));

  String str = null;

  System.out.println("Enter your value:");

  str = br.readLine();

  System.out.println("your value is :"+str);

  }

  /**

  * 从控制台接收一个字符

  * 然后打印到控制台上

  * @throws IOException

  */

  public void printConsoleChar() throws IOException

  {

  System.out.print("Enter a Char:");

  char i = (char) System.in.read();

  System.out.println("your char is :"+i);

  }

  }

posted @ 2011-10-08 15:58  springMVC3.1例子  阅读(239)  评论(0编辑  收藏  举报