从键盘获取输入System.in、InputStream、InputStreamReader、BufferReader

package com.zeph.systemin;

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

public class TestSystemIn {
public static void main(String[] args) {
InputStream is = System.in;
InputStreamReader isr = new InputStreamReader(is);
BufferedReader br = new BufferedReader(isr);
try {
String str = null;
while (!(str = br.readLine()).equals("")) {
System.out.println(str);
}
} catch (IOException e) {
e.printStackTrace();
}
try {
br.close();
isr.close();
is.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}