原谅我啥都不懂就好奇, 发现个好玩的东西

String shuru="";
BufferedReader stdin=new BufferedReader(new InputStreamReader(System.in));
System.out.print("请输入内容：");
shuru=stdin.readLine();
System.out.println("你刚才输入的是"+shuru);

public static void readFileByLines(String str) {
File file = new File(str);
BufferedReader reader = null;
try {
System.out.println("以行为单位读取文件内容，一次读一行");
reader = new BufferedReader(new FileReader(file));
String tempString = null;
int line = 1;
//一次读一行，读入null时文件结束
while ((tempString = reader.readLine()) != null) {
//把当前行号显示出来
System.out.println("line " + line + ": " + tempString);
line++;
}
reader.close();
}
catch (IOException e) {
e.printStackTrace();
}
finally {
if (reader != null) {
try {
reader.close();
}
catch (IOException e1) {
}
}
}
}