📅  最后修改于: 2022-03-11 14:52:27.996000             🧑  作者: Mango
Scanner in = new Scanner(System.in);
String ip1 = in.nextLine();
if( ip1.matches("^\\d+\\.\\d+") )
System.out.println(ip1+"----is a decimal number");
else
System.out.println(ip1+"----is a not decimal number");