看代碼：
import?java.io.BufferedReader;import?java.io.InputStreamReader;
import?java.io.PrintWriter;
public?class?Demo?{
//?獲得系統換行符
private?static?final?String?LINE_SEP?=?System.getProperty("line.separator");
public?static?void?main(String[]?args)?throws?Exception?{
try?(BufferedReader?in?=?new?BufferedReader(
new?InputStreamReader(System.in)))?{
String?line;
StringBuilder?sBuilder?=?new?StringBuilder();
while?(true)?{
line?=?in.readLine();?//?讀入壹行字符串
if?(line?==?null?||?"exit".equals(line))?{
break;
}
sBuilder.append(line).append(LINE_SEP);
}
//?將?sBuilder?中的數據寫入?log.txt
try?(PrintWriter?writer?=?new?PrintWriter("log.txt"))?{
writer.print(sBuilder.toString());
}
}
}
}
編譯運行：