input
=
new
Scanner(System.in)
Scanner的构造函数要求传一个输入流对象，而System.in就是从控制台接收的输入流，传过来即可
要接收输入
的话，用Scanner有一系列的next方法，比如
int
inputInt
=
input.nextInt()
这样就可以在控制台上输入，并接收一个整数
再如
String
inputString
=
input.next()就可以从控制台接收一个字符串
还有很多next方法，一看就知道啥意思了
package com.testimport java.util.Random
import java.util.Scanner
public class RandomTest {
/**
* @param args
*/
public static void main(String[] args) {
// TODO Auto-generated method stub
System.out.println("请输入字符串：")
Scanner scan = new Scanner(System.in)
String source = scan.next()
int sourceLength = source.length()
int randomLength = 6
if(sourceLength <0){
return
}
Random rand = new Random()
StringBuilder result = new StringBuilder()
for(int i=0i<randomLength){
int randomNum = rand.nextInt(randomLength)
if(randomNum >= sourceLength){
continue
}
i++
System.out.println(randomNum)
result.append(source.charAt(randomNum))
}
System.out.println("随机的6个字符为："+result)
}
}
直接复制可以运行
import java.io.*public class InputName {
public static void main(String[] args) throws IOException {
System.out.println("请输入姓名（结束请敲两次回车键）：")
InputStreamReader keyBoard = new InputStreamReader(System. in )
BufferedReader br = new BufferedReader(keyBoard)
FileWriter writer = new FileWriter("name.txt", true)
String s
while ((s = br.readLine()) != null) {
writer.write(s)
}
writer.flush()
writer.close()
keyBoard.close()
br.close()
}
}
