The class Exception, and hence also all its subclasses, have a method getMessage(), which allows one to extract the string associated to the exception.
Example:
try {
...
}
catch (NumberFormatException e) {
System.out.println("Catched NumberFormatException");
System.out.println(e.getMessage());
}
catch (IOException e) {
System.out.println("Catched IOException");
System.out.println(e.getMessage());
}