Regular expression intercepts a number in a string __ regular expressions

Method One:

String str= "Fsdfdsf12315f15 ha 12";

String regex= "[^0-9]";
Pattern p = pattern.compile (regEx);
Matcher m = p.matcher (str);
String Num=m.replaceall (""). Trim (). toString ();
if (Num.length () ==20)
{
System.out.println ("true");
}
Else
System.out.println ("false");


Method Two:

String str = "xxx 1.,111,111,111,111,11e,+18th";
String regex = "\\d*";
Pattern p = pattern.compile (regex);
Matcher m = p.matcher (str);

while (M.find ()) {
if (! "". Equals (M.group ()))
{
System.out.println ("true");
}else
System.out.println ("false");
}