I have situation where I need to perform certain tasks in case my springboot applications fails to start. Basically I want to release various resources. I tried using #PreDestroy annotation but it did not work as application was not started yet. Is there any way out by which we can perform few actions in case springboot application fails to start
Spring app heavily using threadpool context when start the program , so when the main program fail spring can not manage the standard beans related to spring. you can only start new thread using implements Runnable in main class and no access to spring resources as well , just simple getclassloader().getresourceasstream is available there .
However you can write independence java Agent using -javaagent to do some operation on release resource ,see java.lang.instrument.Instrumentation;
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Mine is a Spring boot application, but doesnt uses any web-feature. It's just used as a command-line app that will be triggered by a CRON in a scheduled interval and then it performs the job and die (is not ever running web app)
In this Job, I would need to make a REST call and would need to use WebClient for the same. Below is my dependency i use to bring in the WebClient
implementation 'org.springframework.boot:spring-boot-starter-webflux'
But this dependency keeps my app running and doesnt allow the job to die once the job is done. I tried excluding netty from the above dependency, but that is resulting in the below error
Caused by: org.springframework.context.ApplicationContextException: Unable to start ReactiveWebApplicationContext due to missing ReactiveWebServerFactory bean.
How to use WebClient and at the same time not to use any Web features ?
Note: I tried giving spring.main.web-application-type=none in my property file and it is helping me to exclude web-feature. But is that the only way ?
It’s not the only way but I think it’s certainly the easiest.
You could manually configure the type of application context that’s used and exclude some auto-configuration classes, but setting the web-application-type property or configuring it programmatically on SpringApplication or SpringApplicationBuilder will achieve the same result with less code and configuration.
Just looking for some information if others have solved this pattern. I want to use Spring Integration and Spring Batch together. Both of these are SpringBoot applications and ideally I'd like to keep them and their respective configuration separated, so they are both their own executable jar. I'm having problems executing them in their own process space and I believe I want, unless someone can convince me otherwise, each to run like they are their own Spring Boot app and initialize themselves with their own profiles and properties. What I'm having trouble with though is the invocation of the job in my SpringBatch project from my SpringIntegration project. At first I couldn't get the properties loaded from the batch project, so I realized I need to pass the spring.active.profiles as a Job Parameter and that seemed to solve that. But there are other things in the Spring Boot Batch application that aren't loading correctly like the schema-platform.sql file and the database isn't getting initialized, etc.
On this initial launch of the job I might want the response to go back to Spring Integration for some messaging on Job Status. There might be times when I want to run a job without Spring Integration kicking off the job, but still take advantage of sending statuses back to the Spring Integration project providing its listening on a channel or something.
I've reviewed quite a few Spring samples and have yet to find my exact scenario, most are with the two dependencies in the same project, so maybe I'm doing something that's not possible, but I'm sure I'm just missing a little something in the Spring configuration.
My questions/issues are:
I don't want the Spring Integration project to know anything about the SpringBatch configuration other than the job its kicking off. I have found a good way to do that reference to the Job Bean without getting my entire batch configuration loading.
Should I keep these two projects separated or would it be better to combine them since I have two-way communication between both.
How should the Job be launch from the integration project. We're using the spring-batch-integration project with JobLaunchRequest and JobLauncher. This seems to run it in the same process as the Spring Integration project and I'm missing a lot of my SpringBootBatch projects initialization
Should I be using a CommandLineRunner instead to force it to another process.
Is SpringApplication.run(BatchConfiguration.class) the answer?
Looking for some general project configuration setup to meet these requirements.
Spring Cloud Data Flow in combination with Spring Cloud Task does exactly what you're asking. It launches Spring Cloud Task applications (which can contain batch jobs) as new processes on the platform you choose. I'd encourage you to check out that project here: http://cloud.spring.io/spring-cloud-dataflow/
I want to run few tasks asynchronously in a web application. My question is which Spring implementation of task executors i should use in a Container managed environment.
I refereed to this chapter in Spring documentation and found few options.
One option I considered is WorkManagerTaskExecutor. This is very simple and works seamlessly with the IBM Websepher server which I'm currently using but this is very specific to IBM Websphere and Oracle Weblogic servers. I don't want to tie my code specifically to one particular implementation as in some test and local regions we are using Jetty container & this implementation creates problems to run the code in Jetty.
Other options like SimpleThreadPoolTaskExecutor does not seem to be best fit to leverage thread pooling in container managed environment and I don't want to create new thread myself.
Could you pleas suggest how do I go about this. Any pointers to a sample implementation will be great help.
As usual, it depends. If you rely on the container's thread management and want to be able to set thread pools on its admin interface or if you're application is not the only app inside the container or you use specific features like setting thread pool priorities for EJB or JMS you should add support for the WorkManagerTaskExecutor and make it configurable. If not, you can use whatever you want cause in the end threads are just threads. Since Spring is an IOC container you can do it. To use the same app everywhere I wouldn't suggest to change the XML config per app version. Rather
use profiles with configuration to set the executor type and inside your java config return the proper bean type. If you use Jetty you should have a configuration for the thread pool sizes to to be able to tune it.
use spring boot like auto configuration which usually rely on available classes on classpath (#ConditionalOnClass). If your weblogic or websphere specific classes are available or any other container specific thing like env variables you can create the WorkManagerTaskExecutor
With both of these you can deploy the same war everywhere.
We are using cucumber-jvm to write an integration test layer in our application. One of the challenges we are finding is managing the database between the tests and the web application.
A typical scenario is that we want to persist some entities in a Given step of a scenario, then perform some actions on the user interface that may, in turn, persoist more entities. At the end, we want to clean the database. Because the cucumber-jvm tests are in one jvm and the web application is running in another jvm we cannot share a transaction (at least in a way of which I am aware) so the database must be cleaned manually.
My initial thought was to use an Embedded Tomcat server running off of an embedded in-memory database (HSQLDB) in the same JVM as the cucumber-jvm test. This way we might be able to share a single spring container, and by extension a single transaction, from which all objects could be retrieved.
During my initial tests it looks like Spring gets loaded and configured twice: once when the test starts and the cucumber.xml is read, and a second time when the embedded tomcat starts and the web application reads its applicationContext.xml. These appear to be in two completely separate containers because if I try to resolve an object in one container that is specified in the other container then it doesn't resolve. If I duplicate my configuration then I get errors about duplicate beans with the same id.
Is there a way that I can tell Spring to use the same container for both my test application and the embedded tomcat?
I'm using Spring 3.2.2.GA and Embedded Tomcat 7.0.39 (latest versions of both libraries).
Am I crazy? Do I need to provide more technical details? Apologies if I use some incorrect terminology.
Thanks
p.s. If my problem seems familiar to you and you can suggest an alternative solution to the one I am trying, please let me know!
Jeff,
It is normal that spring is loaded twice. There are two places where two spring contexts are created:
In the servlet container listener org.springframework.web.context.ContextLoaderListener that is configured in web.xml. This one reads its configuration from the file set by the context-param contextConfigLocation.
In the implementation of ObjectFactory provided by cucumber-spring plugin cucumber.runtime.java.spring.SpringFactory. This one reads its configuration from cucumber.xml.
The two spring contexts are totally different and their instances are kept in two different places. As a servlet context attribute for the former and kept by the JavaBackend for the latter.
When starting the embedded tomcat, it is possible to get access to the servlet context and thus set ourself the spring context used bt tomcat with the one from cucumber. But, spring has a special class called WebApplicationContext for context used in a servlet container. The cucumber SpringFactory on other hand creates its context through ClassPathXmlApplicationContext. So unless there is a way to specify the type of application context from the xml config, we will have to provide an ObjectFactory that shoots a WebApplicationContext.
What we can do is to have two web.xml. One for the normal and one for the test. For the test, we use our version of the ContexLoader listener.
I have a web application that uses Struts2 + Spring for the resource injection, basically my DAO. Now I would like to create a thread that periodically polls the database and, if needed, send email notifications to users.
I would like to know how I can implement this in a way that this thread can use my DAO. I haven't been able to manage Spring to inject it the way I've done it. So I would like to hear suggestions and see if someone can point me to the right way.
Right now I have a thread started by a ServletContextListener, that just creates a timer and schedules an action every 5 minutes. But I can't get this action to use my DAO. I don't have any need to use this structure, I'm open to using whichever solution works.
Thanks for your help!
Edit: As axtavt suggested, I used Spring task Execution Scheduling and it works perfectly, the thing is that my task gets injected with the DAO but then I get LazyInitializationException every time I try to access a property of my fetched objects, any suggestion on how to solve that??
Perhaps the best option is to use Spring's own scheduling support, see 25. Task Execution and Scheduling (if necessary - with Quartz, see 25.6 Using the OpenSymphony Quartz Scheduler). This apporach allows you to configure your scheduled action as Spring beans, so you can wire them with other beans such as DAO.
Alternatively, you can use the following to obtain any Spring bean in web application (for example, to obtain DAO from your thread):
WebApplicationContextUtils.getWebApplicationContext(servletContext).getBean(...)