Spring Integration

[Siddharth Bhargava]

Hi Team,

I have a requirement that I need to poll a particular location in windows or unix for the existence of a file and as and when a file comes then report the same with a success. If the file does not come within the stipulated time duration say 30 mins. then the program would return an error "Particular file was not found during the time interval".

I searched the net and figured out that we would be using Spring integration for the same. I am new to Spring integration.

Please if someone could guide me on how to solve my problem stmt.

Thanks and Regards,
Sid.

[Tim Cooke]

There are many many ways for you to solve your problem, none of which "require" you to use Spring. You can of course if you wanted to but it wouldn't necessarily help.

You don't even need Java. I could probably write a bash or Python script in an afternoon that would do this (others more savvy with scripting could probably do it in 10 minutes).

[Siddharth Bhargava]

Tim Cooke wrote:There are many many ways for you to solve your problem, none of which "require" you to use Spring. You can of course if you wanted to but it wouldn't necessarily help.

You don't even need Java. I could probably write a bash or Python script in an afternoon that would do this (others more savvy with scripting could probably do it in 10 minutes).

Thanks Tim but I would like to use Spring only. Would I need to use Spring integration for the same ? Please do let me know as to how to go about it.

[Tim Cooke]

Siddharth Bhargava wrote:I would like to use Spring only

Why?

[Tim Cooke]

I'll elaborate a little... What part of the problem are you hoping to solve with Spring?

"Spring integration" is not a thing. Those articles you found on the "net" were probably just talking about adding Spring into your application.

[Jayesh A Lalwani]

I would just implement this as a Quartz job that polls the location at schedule intervals. I'm not very familiar with Spring Integration. I don't know if it provides a better way

[Siddharth Bhargava]

Jayesh A Lalwani wrote:I would just implement this as a Quartz job that polls the location at schedule intervals. I'm not very familiar with Spring Integration. I don't know if it provides a better way

I understand that there might be many ways but we are using Spring and I found out that Spring integration is the way to go so wanted some inputs on the same as I am new in it.

[Tim Cooke]

Siddharth Bhargava wrote:... we are using Spring ...

Would I be assuming correctly if I took from this that you are writing a new feature for an existing application that uses Spring?

Regardless, I have a number of quesitons:

Polling: How often?

Report success: How? UI output? Return value? Log message? DB call? Remote call?

Report error: How? UI? Return value? Log? DB? Remote? Exception? System exit?

I still maintain that "Spring Integration" is not a thing. The Spring framework has a number of features that solve, or make easier, a number of problems but unfortunately in this instance I do not know what particular problem you are hoping to solve with it so cannot suggest how you would use it. To say you want to solve your problem with "Spring integration" just doesn't make sense as a sentence. Perhaps you can point us to the websites that you have found? That might at least help me understand what you think it will do for your application.

Unless of course you're talking about this Spring-Integration project?? In which case you are about to massively over engineer your application for no good reason and I would recommend you leave it alone and go with something much simpler.

[Siddharth Bhargava]

Tim Cooke wrote:

Siddharth Bhargava wrote:... we are using Spring ...

Would I be assuming correctly if I took from this that you are writing a new feature for an existing application that uses Spring?

Regardless, I have a number of quesitons:

Polling: How often?

Report success: How? UI output? Return value? Log message? DB call? Remote call?

Report error: How? UI? Return value? Log? DB? Remote? Exception? System exit?

I still maintain that "Spring Integration" is not a thing. The Spring framework has a number of features that solve, or make easier, a number of problems but unfortunately in this instance I do not know what particular problem you are hoping to solve with it so cannot suggest how you would use it. To say you want to solve your problem with "Spring integration" just doesn't make sense as a sentence. Perhaps you can point us to the websites that you have found? That might at least help me understand what you think it will do for your application.

Unless of course you're talking about this Spring-Integration project?? In which case you are about to massively over engineer your application for no good reason and I would recommend you leave it alone and go with something much simpler.

Hi Tim,

You are correct. I am indeed writing a new feature for an existing application that uses Spring.

Here are the answers to your queries:

Polling: How often?

: Well this is configurable. Currently its value is 5 seconds.

<int:poller id="poller" fixed-delay="5000" /> 

Report success: How? UI output? Return value? Log message? DB call? Remote call?

: Success would reported by Logging (Log message).

Report error: How? UI? Return value? Log? DB? Remote? Exception? System exit?

: Error would also be reported by Logging (Log message).

I understand that "Spring integration" is not a thing. Again I would like to re-iterate that I would like to solve my problem using "Spring Integration" as it fits into my requirements and would solve my problem in a much easier and cleaner way. Also its my requirement and my organisation has asked me to do using "Spring integration". I would like to solve my whole issue using "Spring Integration"which is - to poll a given location (in say an interval of 5 sec.) for a file (with a given pattern) and then do some processing on the file - say copy the file to another location. Following are some of the URLs (websites) which I have searched for the same:

http://java.dzone.com/articles/getting-started-spring-0
https://thinkbiganalytics.com/ingestion-with-spring-integration/
http://java-success.blogspot.in/2013/01/spring-integration-polling-for-file-and.html
http://www.javacodegeeks.com/2013/05/spring-integration-file-polling-and-tests.html
http://stackoverflow.com/questions/14171283/spring-integration-file-reading-the-file-by-inbound-channel-adapter-before-it
http://docs.spring.io/spring-integration/docs/4.0.0.RELEASE/reference/html/files.html


Waiting for your reply and thoughts.

Thanks and Regards,
Sid.

[Jesus Angeles]

Hi Siddharth,

Indeed, Spring Integration will give you a clean solution for that part of your system (polling for files).

Reading those links you gave would be very helpful.

Look for a simple file-polling example and understand it fully.

A good reference is the Spring Integration in Action book.

[Siddharth Bhargava]

Jesus Angeles wrote:Hi Siddharth,

Indeed, Spring Integration will give you a clean solution for that part of your system (polling for files).

Reading those links you gave would be very helpful.

Look for a simple file-polling example and understand it fully.

A good reference is the Spring Integration in Action book.

Hi Jesus,

Thanks for your reply. I understand that Spring Integration would give me a clean solution for my requirements.

I read the links but I am not able to follow everything what is given in them. In fact I started writing a program but I am facing many many issues in the form of exceptions which I am not able to solve. I looked for a file polling example on the net but its doesn't seem to be working.

Following is my xml configuration file:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
	xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:int="http://www.springframework.org/schema/integration"
	xmlns:int-file="http://www.springframework.org/schema/integration/file"
	xsi:schemaLocation="http://www.springframework.org/schema/beans
    http://www.springframework.org/schema/beans/spring-beans.xsd
    http://www.springframework.org/schema/integration
    http://www.springframework.org/schema/integration/spring-integration.xsd
    http://www.springframework.org/schema/integration/file
    http://www.springframework.org/schema/integration/file/spring-integration-file.xsd">

	<int-file:inbound-channel-adapter id="incomingFiles"
		directory="file:${myapp.incomingFile.path}" prevent-duplicates="true"
		filename-regex="${BMTS_SS.filenameRegex}">

		<int:poller id="poller" fixed-delay="5000" />

	</int-file:inbound-channel-adapter>

</beans>

And following is the exception which I am getting and which I am unable to solve even by searching on the net.

Exception in thread "main" org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'incomingFiles.adapter': Cannot resolve reference to bean 'incomingFiles.adapter.source' while setting bean property 'source'; nested exception is org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'incomingFiles.adapter.source': FactoryBean threw exception on object creation; nested exception is java.lang.NoClassDefFoundError: org/springframework/integration/MessagingException
	at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:328)
	at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveValueIfNecessary(BeanDefinitionValueResolver.java:107)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.applyPropertyValues(AbstractAutowireCapableBeanFactory.java:1456)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1197)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:537)
	at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:475)
	at org.springframework.beans.factory.support.AbstractBeanFactory$1.getObject(AbstractBeanFactory.java:304)
	at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:228)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:300)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
	at org.springframework.beans.factory.support.DefaultListableBeanFactory.preInstantiateSingletons(DefaultListableBeanFactory.java:681)
	at org.springframework.context.support.AbstractApplicationContext.finishBeanFactoryInitialization(AbstractApplicationContext.java:760)
	at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:482)
	at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:139)
	at org.springframework.context.support.ClassPathXmlApplicationContext.<init>(ClassPathXmlApplicationContext.java:83)
	at com.queryutility.jefferies.fileutility.App.main(App.java:28)
Caused by: org.springframework.beans.factory.BeanCreationException: Error creating bean with name 'incomingFiles.adapter.source': FactoryBean threw exception on object creation; nested exception is java.lang.NoClassDefFoundError: org/springframework/integration/MessagingException
	at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:151)
	at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.getObjectFromFactoryBean(FactoryBeanRegistrySupport.java:103)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getObjectForBeanInstance(AbstractBeanFactory.java:1514)
	at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:252)
	at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:195)
	at org.springframework.beans.factory.support.BeanDefinitionValueResolver.resolveReference(BeanDefinitionValueResolver.java:320)
	... 15 more
Caused by: java.lang.NoClassDefFoundError: org/springframework/integration/MessagingException
	at org.springframework.integration.file.FileReadingMessageSource.<init>(FileReadingMessageSource.java:77)
	at org.springframework.integration.file.FileReadingMessageSource.<init>(FileReadingMessageSource.java:96)
	at org.springframework.integration.file.config.FileReadingMessageSourceFactoryBean.initSource(FileReadingMessageSourceFactoryBean.java:128)
	at org.springframework.integration.file.config.FileReadingMessageSourceFactoryBean.getObject(FileReadingMessageSourceFactoryBean.java:98)
	at org.springframework.integration.file.config.FileReadingMessageSourceFactoryBean.getObject(FileReadingMessageSourceFactoryBean.java:36)
	at org.springframework.beans.factory.support.FactoryBeanRegistrySupport.doGetObjectFromFactoryBean(FactoryBeanRegistrySupport.java:144)
	... 20 more
Caused by: java.lang.ClassNotFoundException: org.springframework.integration.MessagingException
	at java.net.URLClassLoader$1.run(Unknown Source)
	at java.security.AccessController.doPrivileged(Native Method)
	at java.net.URLClassLoader.findClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
	at java.lang.ClassLoader.loadClass(Unknown Source)
	... 26 more

I would surely be purchasing the book "Spring Integration in Action" after some due practice in it.

Please do help me in solving my exception.

Thanks and Regards,
Sid.

[Jesus Angeles]

The error suggests a jar is missing in your classpath.

[Siddharth Bhargava]

Jesus Angeles wrote:The error suggests a jar is missing in your classpath.

I tried to search for the error in the net but I am unable to find out which jar is missing.

Its getting really frustrating.

[Jesus Angeles]

I normally use findjar.com or google to find out what jar it belongs to. Then check your classpath.

[Tim Cooke]

Sid, I still don't think you need Spring Integration to solve your problem and I have been trying to suggest to you that you can achieve the same thing in a much simpler way. You are adding significant complexity where it is not needed.

But... You are intent on using it, and I have no experience using it so I'm out. Good luck.