ERROR - ConversionException - Possible Causes of ConversionException

Exception Thrown By:Cause
Eclipse API AbstractParameterValueConverter public abstract String convertToString(Object parameterValue) if a string reference or
serialization cannot be provided for the parameter.
Apache Wicket FormComponent public void validate() If input
can't be converted.
Apache Wicket Strings public static Boolean toBoolean(String s) when s is
not a valid value.
Apache Wicket Strings public static char toChar(String s) when the string is
longer or shorter than 1 character.