in src/main/java/org/apache/nifi/processor/util/StandardValidators.java [93:110]
public ValidationResult validate(final String subject, final String value, final ValidationContext context) {
if (context.isExpressionLanguageSupported(subject) && context.isExpressionLanguagePresent(value)) {
return new ValidationResult.Builder().subject(subject).input(value).explanation("Expression Language Present").valid(true).build();
}
String reason = null;
try {
final int intVal = Integer.parseInt(value);
if (intVal <= 0) {
reason = "not a positive value";
}
} catch (final NumberFormatException e) {
reason = "not a valid integer";
}
return new ValidationResult.Builder().subject(subject).input(value).explanation(reason).valid(reason == null).build();
}