Java judges whether a string is a numeric value, and java judges a string value.

Java judges whether a string is a numeric value, and java judges a string value.

You can use a regular expression to determine whether a string is a numeric value. The simpler method is to convert the string to Float or Double, and then capture the NumberFormatException error. If there is an error, it means it is not a value. If there is no error, it means it is a value.

Public static boolean isFloat (String str) {try {Float. parseFloat (str); return true;} catch (NumberFormatException e) {return false ;}}

In the same way, you can determine whether a string is an integer.