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AWS cron expression to run a job every 2 days once

I have a requirement to schedule a job in AWS CloudWatch events to be run once in every two days. I am using the below expression but getting a error Parameter ScheduleExpression is not valid
cron(0 0 */2 * ? *)
The below is the java code,
String cronExpression = "cron(0 0 */2 * ? *)"
PutRuleRequest request = new PutRuleRequest();
request
.withName(eventName)
.withRoleArn("arn:aws:iam::****")
.withScheduleExpression(cronExpression)
.withState(RuleState.ENABLED);
PutRuleResult result = cloudwatchConfig.cloudwatch().putRule(request);

cron(0 0 1/2 * ? *)
You can verify here.

If you put your syntax into cloudwatch, it too will report the same error you are seeing in the terraform,but fix it simple
cron(0 0 1-31/2 * ? *)
The explanation for each field is here: https://docs.aws.amazon.com/AmazonCloudWatch/latest/events/ScheduledEvents.html
1-31 covers all the possible number of days in a month

How to configure cronSchedule() / cron expression in Quartz library to run same job every day at 11am, 12am, 15am, 17am etc?

I am using Quartz library to add cron timer to my application.
Sample usage is explained here, specifying run periodicity in this API is done thru so-called "cron string" (cron expression) - it is well-explained in examples here and in official docs here.
CronTrigger trigger = newTrigger()
.withIdentity("trigger1", "group1")
.withSchedule(cronSchedule("0/20 * * * * ?")) // cron string
.build();
I understand how to run a task specifying starting point + periodicity (say, at 11am every day, every Friday, etc).
But I need to run it every day at 11am, 12am, 3pm, 7pm etc - I can just enumerate exact times. How can I specify that? I need same task (job) be executed every day exactly at these many times.
It is stupid to create so many Trigger(s), each with separate cron expression. Is there a nice solution?
Here, docs say:
, - used to specify additional values. For example, “MON,WED,FRI” in
the day-of-week field means “the days Monday, Wednesday, and Friday”.
So maybe this works: "0 0 11am,12am,3pm,7pm * * ?" ?
P.S. Or all I can do is to create a separate Trigger for every hour and then add all such Triggers (with same job) to Scheduler like
myScheduler.scheduleJob(sameJob, trigger11am);
myScheduler.scheduleJob(sameJob, trigger12am);
myScheduler.scheduleJob(sameJob, trigger3pm);
myScheduler.scheduleJob(sameJob, trigger7pm);

Yes, this is the way it can be done:
// setup CronTrigger
// misfire policies (when app was down at scheduled time):
// https://www.nurkiewicz.com/2012/04/quartz-scheduler-misfire-instructions.html
Trigger trigger = TriggerBuilder
.newTrigger()
.withIdentity("triggerName", "myGroupName")
.withSchedule(
// at 11:30am, 12:30am, 03:30pm, 06:30pm, etc every day, including Sunday, Monday, days-off
CronScheduleBuilder.cronSchedule("0 30 11,12,15,18,21,23 * * ?")
// don't run missed jobs (missed when app was down)
.withMisfireHandlingInstructionDoNothing())
.build();
Here official examples at the bottom confirm it - see "Fire at 2:10pm and at 2:44pm every Wednesday".

Spring Boot : execute a job at a particular Date entered by the user

Im trying to manage scheduled tasks using spring boot. I want to execute my job only one time at a particular date ( specified by the user ).
Here is my Job :
#Component
public class JobScheduler{
#Autowired
JobController controller;
// Retrieving the Date entered by the user
controller.getDateForExecution(); // 2016/05/24 10:00 for example
#Scheduled(???)
public void performJob() throws Exception {
controller.doSomething();
}
There are multiple options for Scheduled annotation such as fixedDelay, fixedRate, initialDelay, cron ... but none of these can accept a Date.
So, how can i execute my method at the specified Date dynamically ( ie depending on the Date insered ) ?
Ps : The method can be executed more than once if the user enter two or more Dates ..

Spring has the TaskScheduler abstraction that you can use: http://docs.spring.io/spring/docs/current/spring-framework-reference/html/scheduling.html#scheduling-task-scheduler
It has a method to schedule execution of a Runnable at a certain Date:
ScheduledFuture schedule(Runnable task, Date startTime);
A little off-topic maybe: If JobController is a Spring Controller (or RestController), I would not autowire it into the JobScheduler. I would inverse it and inject the JobScheduler into the JobController.

Ok I know this is a very old questions but for future references, here's the answer:
You can use cron property, which gives much more control over the scheduling of a task. It lets us define the seconds, minutes ,and hours the task runs at but can go even further and specify even the years that a task will run in.
Below is a breakdown of the components that build a cron expression.
Seconds can have values 0-59 or the special characters , - * / .
Minutes can have values 0-59 or the special characters , - * / .
Hours can have values 0-59 or the special characters , - * / .
Day of month can have values 1-31 or the special characters , - * ? / L W C .
Month can have values 1-12, JAN-DEC or the special characters , - * / .
Day of week can have values 1-7, SUN-SAT or the special characters , - * ? / L C # .
Year can be empty, have values 1970-2099 or the special characters , - * / .
Just for some extra clarity, I have combined the breakdown into an expression consisting of the field labels.
#Scheduled(cron = "[Seconds] [Minutes] [Hours] [Day of month] [Month] [Day of week] [Year]")
For more you can follow this article: https://dzone.com/articles/running-on-time-with-springs-scheduled-tasks

How to validate CronSequenceGenerator cron expressions?

How could I validate cron expressions that are prepared for use of CronSequenceGenerator?
I mean, I cannot wait until the cron executes automatically as I'm defining like monthly intervals.
Is the following correct? How can I be sure?
monthly at midnight: `0 0 0 1 * *`
monthly at 1 am: `0 0 1 1 * *`
weekly, on sunday at midnight: `0 0 0 * * SUN`

The Spring's CronSequenceGenerator
class has a method
isValidExpression(String expression)
which takes the cron expression and returns a boolean.

I guess if you are ok with quartz api then you should use org.quartz.CronExpression.isValidExpression(String s)
Api ref http://quartz-scheduler.org/api/2.2.0/org/quartz/CronExpression.html

Actually I prefer to directly use "new CronSequenceGenerator(cronExpression)" instead of the static method isValidExpression.
Doing the new directly gives you a java.lang.IllegalArgumentExpression with a message telling you where the problem lies.
Unfortunately "isValidExpression" chokes the exception and simply returns false.

Java Scheduler Quartz Cron Trigger Time Setting

I am using Quartz for Scheduling my job in java. I have used "CronTrigger" for setting my time.
I want to fire my Job each day at 11:55 Pm in night. What should i write in the setCronExpression(" ") for having my Job Done. .??
What i thought of the Code is:---
CronTrigger trigger = new CronTrigger();
trigger.setName("runMeJob");
trigger.setCronExpression("0 55 23 * * ?");
Is the above code correct or should i do some modifications in it????

It would be: 0 55 23 1/1 * ? *
There is a nice website exactly for your case: CronMaker
CronMaker is a utility which helps you to build cron expressions.
CronMaker uses Quartz open source scheduler. Generated expressions are
based on Quartz cron format.