如何在JAVA编程中实现从键盘输入？

在书上还只看到有console输入，不过事先要编写一个程序，貌似要用到try、catch语法，不过那些个东西我一点都看不懂，不知道还有没有简单点的方法实现从键盘输入

9 个解决方案

#1





import java.util.Arrays;

import java.util.Scanner;


public class F {


    public static void main(String[] agrs) {

        /*接收数据*/

        System.out.println("数组的大小？");

        Scanner r = new Scanner(System.in);

        int n = r.nextInt();

        System.out.println("输入数组：");

        int[] num = new int[n];

        for (int i = 0; i < n; i++) {

            num[i] = r.nextInt();

        }

        /*排序*/

        Arrays.sort(num);

        /*输出*/

        for (int i : num) {

            System.out.println(i);

        }

    }

}

这是一个简单的例子~实现从键盘键入一个整型数组并排序输出~~
看看吧~~
具体参见相关API~~~~~~

#2

你要实现仅仅是键盘输入还是键盘的监听？

#3

Scanner，I/O流都可以

#4

import java.util.Scanner;

#5

该回复于2011-03-07 13:39:01被版主删除

#6

Scanner r = new Scanner(System.in);
int n = r.nextInt();

#7

可以个Scanner类如1楼写的测试代码。也可以自己写一个控制台输入类。

import java.io.BufferedReader;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.IOException;

/**
A class to read strings and numbers from an input stream.
This class is suitable for beginning Java programmers.
It constructs the necessary buffered reader,
handles I/O exceptions, and converts strings to numbers.
*/

public class ConsoleReader
{  /**
   Constructs a console reader from an input stream
   such as System.in
   @param inStream an input stream
*/
//such as system.in this is the inputstream
public ConsoleReader(InputStream inStream)
{  reader = new BufferedReader
      (new InputStreamReader(inStream));
}

/**
   Reads a line of input and converts it into an integer.
   The input line must contain nothing but an integer.
   Not even added white space is allowed.
   @return the integer that the user typed
*/
public int readInt()
{  String inputString = readLine();
   int n = Integer.parseInt(inputString);
   return n;
}

/**
   Reads a line of input and converts it into a floating-
   point number. The input line must contain nothing but
   a nunber. Not even added white space is allowed.
   @return the number that the user typed
*/
public double readDouble()
{  String inputString = readLine();
   double x = Double.parseDouble(inputString);
   return x;
}

/**
   Reads a line of input. In the (unlikely) event
   of an IOException, the program terminates.
   @return the line of input that the user typed, null
   at the end of input
*/
public String readLine()
{  String inputLine = "";

   try
   {  inputLine = reader.readLine();
   }
   catch(IOException e)
   {  System.out.println(e);
      System.exit(1);
   }

   return inputLine;
}

private BufferedReader reader;
}

#8

这些东西嘛简单啊你问的情况基本是控制台输入
百度上有例子的如果是做页面什么数据都是键盘输入了啊

#9

至于你说要try  catch 块  那个是因为有些东西会产生异常  需要去捕捉异常或是抛出
你只要把你需要执行的代码放在他们之间就可以了   至于异常信息可以在catch块你输出
   当然  也可以在方法名后直接抛出异常  丢给上级自动处理或继续抛出

#1





import java.util.Arrays;

import java.util.Scanner;


public class F {


    public static void main(String[] agrs) {

        /*接收数据*/

        System.out.println("数组的大小？");

        Scanner r = new Scanner(System.in);

        int n = r.nextInt();

        System.out.println("输入数组：");

        int[] num = new int[n];

        for (int i = 0; i < n; i++) {

            num[i] = r.nextInt();

        }

        /*排序*/

        Arrays.sort(num);

        /*输出*/

        for (int i : num) {

            System.out.println(i);

        }

    }

}