Sample code to publish and listen for events with conditions

eventCondition_pom.xml

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
	xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
	<modelVersion>4.0.0</modelVersion>
	<parent>
		<groupId>org.springframework.boot</groupId>
		<artifactId>spring-boot-starter-parent</artifactId>
		<version>1.5.19.RELEASE</version>
		<relativePath/> <!-- lookup parent from repository -->
	</parent>
	<groupId>com.example</groupId>
	<artifactId>demo</artifactId>
	<version>0.0.1-SNAPSHOT</version>
	<name>demo</name>
	<description>Demo project for Spring Boot</description>

	<properties>
		<java.version>1.8</java.version>
	</properties>

	<dependencies>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter</artifactId>
		</dependency>

		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-devtools</artifactId>
			<scope>runtime</scope>
		</dependency>
		<dependency>
			<groupId>org.springframework.boot</groupId>
			<artifactId>spring-boot-starter-test</artifactId>
			<scope>test</scope>
		</dependency>
	</dependencies>

	<build>
		<plugins>
			<plugin>
				<groupId>org.springframework.boot</groupId>
				<artifactId>spring-boot-maven-plugin</artifactId>
			</plugin>
		</plugins>
	</build>

</project>

eventCondition_src_main_java_com_example_demo_DemoApplication.java

package com.example.demo;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.CommandLineRunner;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.context.ApplicationEventPublisher;

@SpringBootApplication
public class DemoApplication implements CommandLineRunner {

	@Autowired
	private ApplicationEventPublisher publisher;

	@Override
	public void run(String... args) throws Exception {
		OrderCreatedEvent event = new OrderCreatedEvent(true);
		publisher.publishEvent(event);
	}

	public static void main(String[] args) {
		SpringApplication.run(DemoApplication.class, args);
	}
}

eventCondition_src_main_java_com_example_demo_MyComponent.java

package com.example.demo;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.context.event.EventListener;
import org.springframework.stereotype.Component;

@Component
public class MyComponent {

    private static final Logger LOGGER = LoggerFactory.getLogger(MyComponent.class);

    @EventListener(condition = "#createdEvent.awesome")
    public void handleOrderCreatedEvent(OrderCreatedEvent createdEvent) {
        LOGGER.info("Awesome event handled");
    }

}

eventCondition_src_main_java_com_example_demo_OrderCreatedEvent.java

package com.example.demo;

public class OrderCreatedEvent {

    public OrderCreatedEvent(boolean awesome) {
        this.awesome = awesome;
    }

    private boolean awesome;

    public boolean isAwesome() {
        return awesome;
    }
}

eventCondition_src_test_java_com_example_demo_DemoApplicationTests.java

package com.example.demo;

import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.boot.test.mock.mockito.MockBean;
import org.springframework.context.ApplicationEventPublisher;
import org.springframework.test.context.junit4.SpringRunner;

import static org.mockito.Mockito.*;

@RunWith(SpringRunner.class)
@SpringBootTest(classes = MyComponent.class)
public class DemoApplicationTests {

	@Autowired
	private ApplicationEventPublisher publisher;
	@MockBean
	private MyComponent myComponent;

	@Test
	public void handleOrderCreatedEvent_shouldExecute_whenAwesome() {
		OrderCreatedEvent event = new OrderCreatedEvent(true);
		publisher.publishEvent(event);
		verify(myComponent).handleOrderCreatedEvent(event);
	}

	@Test
	public void handleOrderCreatedEvent_shouldNotExecute_whenNotAwesome() {
		OrderCreatedEvent event = new OrderCreatedEvent(false);
		publisher.publishEvent(event);
		verify(myComponent, times(0)).handleOrderCreatedEvent(event);
	}

}