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how to run Camel Main so it will keep running, and also use Spring Context XML DSL?

I'm upgrading an old system that was a batch job that used Camel Main to continue running, so that it can basically loop and query a database every few seconds. It also uses Spring for configuration, but doesn't use Spring Boot. It was on Camel 2.x and I'm having to upgrade it to Camel 3.14. The Main class has changed in that time. In addition to being moved to a different package, it has lost the method it was using to add the Spring context, which was setApplicationContextUri("app-context"). There is a configure() method on Main now, but I still don't see a way of adding a Spring context to Main.
Looking at javadocs for the new Main, I see there are methods in MainSupport that reference CamelContext, but they seem to be about creating a blank CamelContext. There is also an autoconfigure(CamelContext) which takes in CamelContext, but it's protected, so I don't see how to call it. I guess without extending Main, which I don't see any use cases or examples for.
Alternatively, if there's a way to do this without using Main, I'm open to that as well.
The Spring and CamelContext are mainly used to set up beans like dataSources and Properties. The Route is defined in the same class that contains the java main() method that is called from the script used to start the whole process (this is the old version):
package com.foo.email.ffdb.listener;
import java.util.Properties;
import javax.annotation.Resource;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.spring.Main;
import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;
import org.springframework.beans.factory.annotation.Autowired;
import com.foo.email.ffdb.util.FireFrgtConstants;
public class EmailDBListener extends RouteBuilder {
private static Logger log = LogManager.getLogger(EmailDBListener.class.getName());
private static String routeId = FireFrgtConstants.EMAIL_ROUTE_ID;
#Autowired
private EmailDBProcessor emaiDBProcessor;
#Resource
private Properties emailProperties;
public static void main(String[] args) throws Exception {
System.out.println("STARTING EMAILDBLISTENER");
log.debug("Starting Email Batch ");
Main main = new Main();
main.setApplicationContextUri("app-context.xml");
main.run();
log.info("Email Batch Started:");
}
#Override
public void configure() throws Exception {
log.debug("configure() ");
from(configureSqlTimer())
.routeId(routeId)
.to("sqlComponent:{{SQL.READ_EMAIL_REQUESTS}}")
.bean("fireForgetServiceMapper", "readEmailRequests")
.process(emaiDBProcessor);
}
private String configureSqlTimer() {
log.debug("configureSqlTimer() ");
String pollingTime = emailProperties.getProperty(FireFrgtConstants.POLLING_TIME);
String sqlTimer = "timer://pollFireFrgtTable?period=" + pollingTime + "s";
return sqlTimer;
}
}

I just had the wrong Main. There is one in camel-main, and another in camel-spring-main. I just needed to use the camel-spring-main, and it started running and staying alive.
Except for a transaction problem I am creating another question for...
But the main program is running

JOOQ is not generating classes

I have a problem with JOOQ framework (3.13.4) along with Spring Boot and Java 8.
The problem is that I'm trying to generate domain classes using java code way (instead of using codegen plugin with maven which had some troubles with custom naming strategy provider). So as first let me show You the #Configuration class which contains (at least I believe that it contains) all of the necessary beans:
import com.ormtester.common.base.Measurer;
import com.ormtester.common.utils.enums.OrmType;
import com.ormtester.datasources.config.RouteableDataSource;
import org.jooq.SQLDialect;
import org.jooq.codegen.GenerationTool;
import org.jooq.impl.DataSourceConnectionProvider;
import org.jooq.impl.DefaultConfiguration;
import org.jooq.impl.DefaultDSLContext;
import org.jooq.impl.DefaultExecuteListenerProvider;
import org.jooq.util.xml.jaxb.Schema;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;
import org.jooq.meta.jaxb.*;
import org.springframework.transaction.annotation.EnableTransactionManagement;
import javax.annotation.PostConstruct;
import java.util.Properties;
#Configuration
#EnableTransactionManagement
public class JooqConfigurator {
private Properties moduleProperties;
private RouteableDataSource routeableDataSource;
public JooqConfigurator(RouteableDataSource routeableDataSource) {
this.routeableDataSource = routeableDataSource;
try {
moduleProperties = new Properties();
moduleProperties.load(JooqConfigurator.class.getClassLoader()
.getResourceAsStream("jooq.properties"));
} catch (Exception ignore) {}
}
#Bean
public DataSourceConnectionProvider connectionProvider() {
return new DataSourceConnectionProvider(routeableDataSource);
}
#Bean
public ExceptionTranslator exceptionTransformer() {
return new ExceptionTranslator();
}
#Bean
public DefaultConfiguration configuration() {
DefaultConfiguration jooqConfiguration = new DefaultConfiguration();
jooqConfiguration.set(connectionProvider());
jooqConfiguration.set(new DefaultExecuteListenerProvider(exceptionTransformer()));
jooqConfiguration.set(SQLDialect.DEFAULT);
return jooqConfiguration;
}
#Bean
public DefaultDSLContext dsl() {
return new DefaultDSLContext(configuration());
}
#PostConstruct
public void generateCode() {
try {
GenerationTool.generate(new org.jooq.meta.jaxb.Configuration()
.withJdbc(new Jdbc()
.withDriver("com.mysql.cj.jdbc.Driver")
.withUrl("jdbc:mysql://localhost:3306/ormtester?useJDBCCompliantTimezoneShift=true&useLegacyDatetimeCode=false&serverTimezone=UTC")
.withUser("root")
.withPassword("root123"))
.withGenerator(new Generator()
.withName("org.jooq.codegen.JavaGenerator")
.withStrategy(new CustomStrategyProvider())
.withDatabase(new Database()
.withName("org.jooq.meta.mysql.MySQLDatabase")
.withIncludes(".*")
.withExcludes("")
.withSchemata(new SchemaMappingType().withInputSchema("ormtester").withOutputSchema("ormtester"))
.withInputCatalog("ormtester")
.withOutputCatalog("ormtester"))
.withTarget(new Target()
.withPackageName("com.ormtester.jooq.domain")
.withDirectory("jooq/src/main/java"))));
} catch (Exception e) {
System.out.println(e.getLocalizedMessage());
}
}
}
RouteableDataSource is a type that extends AbstractRoutingDataSource because in this case I need to have a possibility to change datasource at runtime. This thing is working well in the other regions of the project (or in another words with tools like Hibernate or MyBatis).
As You can see there is a #PostConstruct method which is used for generating domain classes and the problem is that this method doesn't generate any error or something but the classes are also not generated. I've tried to run it using PostgreSQL and Oracle database (of course changing the driver, database name etc.) and the situation is looking exactly the same.
One interesting thing is that when I'm running this code and package com.ormtester.jooq.domain is present - during the method execution domain package is getting removed.
I'd also like to mention that JOOQ autoconfiguration is disabled by excluding JooqAutoConfiguration class through the #SpringBootApplication annotation located at the project's main (starter) class.
IDE is running in administrator's mode and - what can be also interesting - if I will set the breakpoint in the getJavaClassName() method in my custom naming strategy provided (CustomStrategyProvider which extends DefaultGeneratorStrategy class, the breakpoint is reached everytime this method is used.
So does anyone faced the same problem and/or simply can tell me if I'm doing something wrong or something is missing in the code snippet that I've provieded here? I have this problem since about 4 days and now I'm running out of the ideas what can be wrong. I went through the tons of topics on many forums and nothing helped me, including the tutorials on the author's page (which in my opinion simply lacks of important informations).
I'll be really grateful for every help - thanks in advance!

Code generation is a build task, not a runtime task. I can't think of a reasonable scenario where generating code only at runtime would make sense.
The problem is that I'm trying to generate domain classes using java code way (instead of using codegen plugin with maven which had some troubles with custom naming strategy provider)
You have to create a separate maven module (or project) where you build the custom naming strategy, and then add that as a dependency to the jOOQ code generation plugin. This works the same way as with the JPADatabase, where entities have to be placed in a separate maven module.

Purpose of Service Interface Class in Spring Boot

My question is regarding the use of the interface class. I am fairly new to Spring so please bear with me if this is overly simple.
First of all, what is the point of having an IBoxService interface here when you could just declare the find all in BoxService. Secondly, in the controller how is IBoxService being used. Meaning, we are calling IBoxService.findAll(). But, how is this being tied to the BoxService class. What if multiple service classes implemented IBoxService? Is this a java thing or a Spring injection thing. Thanks.
package com.xyz.service;
import com.xyz.model.Box;
import java.util.Set;
public interface IBoxService {
Set<Box> findAll();
}
package com.xyz.service;
import com.xyz.model.Box;
import com.xyz.repository.BoxRepository;
import java.util.Set;
import org.springframework.stereotype.Service;
import lombok.AllArgsConstructor;
import lombok.extern.slf4j.Slf4j;
import org.springframework.transaction.annotation.Transactional;
import org.springframework.beans.factory.annotation.Autowired;
#Service
#AllArgsConstructor
#Slf4j
#Transactional
public class BoxService implements IBoxService {
#Autowired
private BoxRepository boxRepo;
#Override
public Set<City> findAll() {
return (Set<City>) repository.findAll();
}
}
package com.xyz.controller;
import com.xyz.model.Box;
import com.xyz.service.IBoxService;
import java.util.Set;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.*;
#RestController
#RequestMapping("/api/box")
public class BoxController {
#Autowired
private IBoxService boxService;
#GetMapping
public ResponseEntity<Set<Boxes>> allBoxes() {
return (Set<Box>) boxService.findAll();
}
}

There are various reasons why Service layer interfaces are created. The first and most important reason is testability. You can create mocks of service interface and test your code easily, if you cannot create mocks using a mocking library then you can create test stubs.
One more reason is, we can achieve loose coupling between Controller and Service layer. Suppose you want to entirely change the implementation of service, you can create new service implementation and inject that implementation by injecting new bean by qualifier name

Please understand basic Java and use of interface . Spring boot is just abstraction over Java hence all the basic concepts applies as it is.
Coming back to your questions IBoxService is a interface which allows to inject required implementation of it at controller level. As of now only implementation of IBoxServic is BoxService hence it is getting injected automatically. In case you have multiple implementations you need to use qualifier annotation to specify kind of implementation you need to inject. Or you can create object bu yourself using class names
Consider below:
IBoxService is implemented by two classes BoxService and TiffinBoxService
Now in controller you can inject implementation which you want. Which allow us to achieve principle of interface which is hide internal details.
User which is controller in this case doesn't need to know which class is being use internally as we are using reference of interface.
List interface is best example which has ArrayList and LinkedList as implementation classes.
Hope it is useful !!

How to use Apache Camel aggregator

I have a very simple use case in which I want to put together a collection of stings and trying to use aggregator EIP for this. However when trying to start up the route it complains it cannot find an Aggregator Strategy:
java.lang.IllegalArgumentException: AggregationStrategy or AggregationStrategyRef must be set on Aggregate
below is how I can reproduce the issue:
import org.apache.camel.RoutesBuilder;
import org.apache.camel.builder.RouteBuilder;
import org.apache.camel.test.junit4.CamelTestSupport;
import org.junit.Test;
import java.util.Arrays;
import java.util.List;
public class AggregatorTest extends CamelTestSupport {
private static final List<String> LIST = Arrays.asList(new String[] {"one", "two", "three"});
#Override
protected RoutesBuilder createRouteBuilder() throws Exception {
return new RouteBuilder() {
#Override
public void configure() throws Exception {
from("direct:start")
.split().body()
.setHeader("cheese", constant("camembert"))
.aggregate(constant("all"))
.to("mock:end");
}
};
}
#Test
public void shouldAggregateStrings() throws Exception {
sendBody("direct:start", LIST);
}
}
Of course a very easy way to fix this would be to create an Aggregation Strategy implementation and configure my route to use it. However I would like to understand why the way is set up now does not work. According to the camel documentation on here :
By default Camel uses DefaultAggregationCollection and
UseLatestAggregationStrategy, so this simple example will just keep
the latest received exchange for the given correlation Expression
I also noticed DefaultAggregationCollection is no longer part of the camel core. So what I am missing here?

That is the old documentation. The correct documentation is at: http://camel.apache.org/aggregator2
eg the list of EIPs has links to the correct documentation: http://camel.apache.org/eip
You can find examples from those links, and as well in this little example: https://github.com/apache/camel/blob/master/examples/camel-example-aggregate/README.md
And the Camel in Action books has an EIP chapter where the aggregator is covered in much more details as well: http://camel.apache.org/books

I made a small video to demonstrate this EIP pattern using SpringBoot and Camel.
Have a look here: https://youtu.be/IdGuGGVv51Q

Play Framework Dependency Injection

I've been looking all over Google to find some useful information on how to use Guice/Spring DI in Play Framework 2.1
What I want to do is to Inject several Services in some DAO's and vice versa.
Just need some clarification on this - With play 2.1, do you have to use an # annotation within the routes file for DI?
I've looked at this guide here - https://github.com/playframework/Play20/blob/master/documentation/manual/javaGuide/main/inject/JavaInjection.md
and applied the following steps creating a Global class in app and adding the GUICE dependencies in Build.scala but keep on getting a null pointer exception when invoking on the injected object.
Has anyone been able to get DI working in Play 2.1 using Guice? I've seen examples across the internet but they all seem to be using DI within the controller.

I noticed you are using Java. Here is how I got it to work for injecting into a controller.
First, I created the following 4 classes :
MyController:
package controllers;
import play.mvc.*;
import javax.inject.Inject;
public class MyController extends Controller {
#Inject
private MyInterface myInterface;
public Result someActionMethodThatUsesMyInterface(){
return ok(myInterface.foo());
}
}
MyInterface:
package models;
public interface MyInterface {
String foo();
}
MyImplementation2Inject:
package models;
public class MyImplementation2Inject implements MyInterface {
public String foo() {
return "Hi mom!";
}
}
MyComponentModule:
package modules;
import com.google.inject.AbstractModule;
import models.MyInterface;
import models.MyImplementation2Inject;
public class ComponentModule extends AbstractModule {
#Override
protected void configure() {
bind(MyInterface.class).
to(MyImplementation2Inject.class);
}
}
Now the final part, that took me a silly long time to figure out, was to register the module. You do this by adding the following line to the end of the application.conf file, which is located in the conf directory:
play.modules.enabled += "modules.MyComponentModule"
I hope this was helpful to you. :)

I use cake pattern and my own version of Global overriding getControllerInstance
https://github.com/benjaminparker/play-inject
Cheers
Ben

Sorry, this is a late response, but here's our example
https://github.com/typesafehub/play-guice

Have you tried using some different approach to DI than Guice?
We also tried implementing a project with Guice or Spring but ended in registering our dependencies in objects that implement trait such as:
trait Registry {
def userDao: UserDao
...
}
object Registry {
var current: Registry = _
}
object Environnment {
object Dev extends Registry {
val userDao = ...
//implement your environment for develpment here
}
object Test extends Registry {
val userDao = ...
//implement your ennviroment for tests here e.g. with mock objects
}
}
Another good approach wich might fit for you is the cake pattern (just google for it).