Cron Expression Parser

Prerequisites

• Java Development Kit 11 or higher

Building

$ ./gradlew clean build

Running

$ java -jar build/libs/cron-0.0.1.jar  "*/15 0 1,15 * 1-5 /usr/bin/find"

Assumptions

• The ? character, which in some implementations denotes no specific value is not supported.
• No semantic checks are done so e.g. non-existing February, the 30th - 0 0 31 2 * /usr/bin/find is a valid cron expression.

Missing parts

• JAN–DEC and SUN–SAT values for month and day of week fields.
• Thorough input validation.