Package com.mgnt.lifecycle.management.backgroundrunner

This package contains infrastructure that can run user implemented Task classes in a separate thread at configured time interval.

See: Description

Interface Summary

Interface	Description
BackgroundRunnable	This is the interface that a user periodically executed Task class must implement.

Class Summary

Class	Description
BackgroundRunnableFactory	This class is part of the framework and probably will not be accessed externally
BackgroundThreadsRunner	This class is part of the framework and probably will not be accessed externally.
BaseBackgroundRunnable	This is the base class for any user defined periodic Task classes See source code example in package com.mgnt.lifecycle.management.backgroundrunner.example that demonstrates how it is done

Package com.mgnt.lifecycle.management.backgroundrunner Description

This package contains infrastructure that can run user implemented Task classes in a separate thread at configured time interval. In order to create such task user will need to create a class that extends BaseBackgroundRunnable class and override 4 methods: BaseBackgroundRunnable.initParamsForSpecificImplementation()
, BackgroundRunnable.getTaskExecutionInterval()
, BackgroundRunnable.setParamValue(com.mgnt.utils.entities.TimeInterval, java.lang.String)
and Runnable.run()
. This infrastructure is intended for use with Spring framework although it may be used in other environments as well. Before going any farther lets address a very glaring question. Why would anyone want to use this infrastructure which already looks like requiring hard work if Spring provides an annotation @Scheduled that can be used for any method and that would work just fine. Well The annotation @Scheduled takes time interval property i.e. the time between 2 sequential executions in milliseconds or as a cron expression. Neither of those formats are user friendly. Imagine that you need to run a task each 9 hours. So you parameter that you will have to provide to @Scheduled annotation would look like @Scheduled(fixedRate = 32400000). (32400000 is number of milliseconds in 9 hours) This is hardly intuitive... What if you could write @Scheduled(fixedRate = 9h)? Well, that would be great, but you can not (at least with currently available latest versions). This is what this infrastructure provides. Especially if you annotate one of your properties with annotation @Value("${task.execution.interval}") and then you will have a properties file that will have a property task.execution.interval=9h instead of task.execution.interval=32400000. So there is a trade-off here. This infrastructure definitely requires more effort from a programmer then mere method annotation with @Scheduled, but provides very intuitive and humanly readable way to define time interval properties. Internally this framework uses utility provided by this library to parse those time intervals. (For details see TextUtils.parseStringToTimeInterval(java.lang.String)) Also this infrastructure allows you to parse other time interval properties (if you class has any) with the same format.

package com.mgnt.lifecycle.management.backgroundrunner.example contains working source code that demonstrates how this infrastructure is used. Assume that you have implemented your tasks TypeOneTask and TypeTwoTask (The same classes that are used in package com.mgnt.lifecycle.management.backgroundrunner.example). If you work in Spring environment you will need to annotate those classes with annotation Component (or define them as beans in your xml configuration files) and you will need to add one more declaration in your xml configuration file:
<bean id="backgroundThreadsRunner" name="backgroundThreadsRunner" class="com.mgnt.lifecycle.management.backgroundrunner.BackgroundThreadsRunner" depends-on="typeOneTask,typeTwoTask"/> The reason is that your tasks must be instantiated before instance of BackgroundThreadsRunner is created by Spring

For the details on how to implement your tasks please refer to source code in the package com.mgnt.lifecycle.management.backgroundrunner.example the code there is concise and well commented with detailed explanation