Scheduled Apex Class in Salesforce

Hello friends, we will discuss How Scheduled Apex Class in Salesforce. further, we will discuss how to schedule a class that runs daily.

Schedule Apex classes to run at specific times by implementing the Schedulable interface first, then specifying the schedule through either the Schedule Apex page in Salesforce’s user interface or the System.schedule method.

Also check this : Relationship Query in Apex Salesforce

Key Highlights :

1. Schedulable Apex class should by implementing the Schedulable interface.
2. Can Schedule by Salesforce directly.

Process :

Run Every 30 Minute :

ScheduledApexJob obj = new ScheduledApexJob();
 
String sch1 = '0 0 * * * ?';
System.schedule('Schedule Job1', sch1, obj);
 
String sch2 = '0 30 * * * ?';
System.schedule('Schedule Job2', sch2, obj);

Run Daily on a particular Time: Below code schedule, a class and class will run daily 5 AM.

ScheduledApexJob obj = new ScheduledApexJob();
 
String sch1 = '0 0 5* * * ?';
System.schedule('Schedule Job1', sch1, obj);

Runs only once for a particular date-time: Below code schedule a class for after 2 and run only once.

ScheduledApexJob obj = new ScheduledApexJob();

Datetime next = System.now().addhours(2);
String sch1 = next.second() + ' ' + next.minute() + ' ' + next.hour() + ' ' +
              next.day() + ' ' + next.month() + ' ? ' + next.year();

Integer randomNumber = Integer.valueof((Math.random() * 1000000));

System.schedule('Run after 2 hours '+randomNumber, cron, obj);

You can also create crone expression by this website http://www.cronmaker.com/

Reference :

1. Apex Scheduler