Frequently problem solutions in Chrl Cron Service Framework Summary
Frequently problem solutions in Chrl Cron Service Framework Summary
Chrl Cron Service is a Java framework for processing timing tasks.It is based on the CRON expression syntax, which can easily set the execution time and cycle of tasks.However, some common problems are encountered when using the Chrl Cron Service framework.This article will summarize these common problems and provide corresponding solutions, and provide some Java code examples to illustrate how to solve these problems.
1. CRON expression grammar error
In Chrl Cron Service, the execution time of the task is defined by the CRON expression.If the CRON expression is wrong, the task may not be performed as expected.The method of solving this problem is to check the syntax of CRON expression and correct the error.The following is an example that demonstrates how to create a task once a day.
import ch.ralscha.extdirectspring.annotation.ExtDirectMethod;
import org.springframework.stereotype.Service;
import org.springframework.scheduling.annotation.Scheduled;
@Service
public class MyTaskService {
@Scheduled(cron = "0 0 0 * * ?")
\tpublic void myTask() {
\ t // code for executing tasks
\t}
}
2. Timing task execution fails
Sometimes the task may not be executed at the scheduled time.This may be caused by some external factors, such as excessive system loads, or problems in the task itself.The method of solving this problem is to check the use of the system resources and the correctness of the task code.You can also use a log to track the execution of the task in order to find the problem.The following is an example that demonstrates how to create a task that performs every one hour and records the task execution.
import ch.ralscha.extdirectspring.annotation.ExtDirectMethod;
import org.springframework.stereotype.Service;
import org.springframework.scheduling.annotation.Scheduled;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@Service
public class MyTaskService {
private static final Logger LOGGER = LoggerFactory.getLogger(MyTaskService.class);
@Scheduled(cron = "0 0 * * * ?")
\tpublic void myTask() {
\ tlogger.info ("Task starts to execute");
\ t // code for executing tasks
\ tlogger.info ("task execution complete");
\t}
}
3. Equal execution task
In some cases, multiple tasks may need to be performed at the same time, and Chrl Cron Service defaults to do not support task concurrent execution.The method of solving this problem is to use different threads to perform each task to achieve concurrent execution.The following is an example that demonstrates how to create multiple tasks concurrent execution.
import ch.ralscha.extdirectspring.annotation.ExtDirectMethod;
import org.springframework.stereotype.Service;
import org.springframework.scheduling.annotation.Async;
import org.springframework.scheduling.annotation.Scheduled;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
@Service
public class MyTaskService {
private static final Logger LOGGER = LoggerFactory.getLogger(MyTaskService.class);
@Scheduled(cron = "0 0 * * * ?")
@Async
\tpublic void task1() {
\ tlogger.info ("Mission 1 Start Execution");
\ t // Code of executing task 1
\ tlogger.info ("Mission 1 executes");
\t}
@Scheduled(cron = "0 30 * * * ?")
@Async
\tpublic void task2() {
\ tlogger.info ("Task 2 Start Execution");
\ t // The code of executing task 2
\ tlogger.info ("Mission 2 executes");
\t}
}
These are solutions to some common problems in the Chrl Cron Service framework, as well as the corresponding Java code examples.By following these solutions, you can better use the Chrl Cron Service framework to handle timing tasks.
