java判断字符串是否为数字的方法小结

public static boolean isNumeric(String str){ for (int i = str.length();--i>=0;){    if (!Character.isDigit(str.charAt(i))){  return false;  } } return true;}

public static boolean isNumeric(String str){   Pattern pattern = Pattern.compile("[0-9]*");   return pattern.matcher(str).matches();  } 

public static boolean isNumeric(String str){  for(int i=str.length();--i>=0;){   int chr=str.charAt(i);   if(chr<48 || chr>57)     return false;  }  return true;}