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Ektorp dependency crashing Spring boot application

I`m making a web application. The back-end is in Java, and I use Spring. For the database I use CouchDb and I want to use Ektorp, but here comes the problem. It crashes when I add the Ektorp dependency. It compiles, but when I try to run, I get the errors from below.
Exception in thread "main" java.lang.IllegalArgumentException: Cannot instantiate interface org.springframework.context.ApplicationListener : org.springframework.boot.context.logging.ClasspathLoggingApplicationListener
at org.springframework.boot.SpringApplication.createSpringFactoriesInstances(SpringApplication.java:450)
at org.springframework.boot.SpringApplication.getSpringFactoriesInstances(SpringApplication.java:429)
at org.springframework.boot.SpringApplication.getSpringFactoriesInstances(SpringApplication.java:420)
at org.springframework.boot.SpringApplication.<init>(SpringApplication.java:270)
at org.springframework.boot.SpringApplication.<init>(SpringApplication.java:249)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1260)
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1248)
at QEasyApplication.main(QEasyApplication.java:18)
Caused by: java.lang.NoClassDefFoundError: org/springframework/context/event/GenericApplicationListener
at java.base/java.lang.ClassLoader.defineClass1(Native Method)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1016)
at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:174)
at java.base/jdk.internal.loader.BuiltinClassLoader.defineClass(BuiltinClassLoader.java:802)
at java.base/jdk.internal.loader.BuiltinClassLoader.findClassOnClassPathOrNull(BuiltinClassLoader.java:700)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClassOrNull(BuiltinClassLoader.java:623)
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:581)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
at java.base/java.lang.Class.forName0(Native Method)
at java.base/java.lang.Class.forName(Class.java:398)
at org.springframework.util.ClassUtils.forName(ClassUtils.java:275)
at org.springframework.boot.SpringApplication.createSpringFactoriesInstances(SpringApplication.java:442)
... 7 more
Caused by: java.lang.ClassNotFoundException: org.springframework.context.event.GenericApplicationListener
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:583)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:178)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:521)
... 20 more
Process finished with exit code 1
I tried changing to different versions of Ektorp or spring boot but nothing worked. Down below is my Maven pom file. What could be the problem?
<?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>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-dependencies</artifactId>
<version>2.1.3.RELEASE</version>
<type>pom</type>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
<version>2.1.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-thymeleaf</artifactId>
<version>2.1.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-logging</artifactId>
<version>2.1.3.RELEASE</version>
</dependency>
<dependency>
<groupId>org.ektorp</groupId>
<artifactId>org.ektorp.spring</artifactId>
<version>1.4.4</version>
</dependency>
</dependencies>
</project>

Well it seems that org.springframework.context.event.GenericApplicationListener is not on your classpath. It resides in spring-context.
You state, in other words your pom.xml states, that someone should provide spring-boot-dependencies for you? I think you confused the provided and the import Maven scopes:
provided – "you expect the JDK or a container to provide the dependency at runtime"
import – "It indicates the dependency to be replaced with the effective list of dependencies in the specified POM's section."
So two possibilities:
switch the runtime scope of spring-boot-dependencies to import
even better, let Spring Boot manage as many dependencies as possible for you and put the following parent pom in place, to leverage the full potential of Spring Boot:
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.1.3.RELEASE</version>
</parent>

Spring boot app with Netfilx Eureka fails to start after being packaged into a fat jar

So I have been following this Microservices with Spring Boot guide and everything seems to work as expected in the IDE(intelliJ IDEA), the Eureka Server starts and functions as expected.
However, a problem occured after I exported my Eureka server as a fat jar.
To package the Eureka server into a fat jar I used mvn clean package in the terminal which has always worked for me.
After that when I tried to run the jar using java -jar myjar.jar I got the following exception
org.springframework.context.ApplicationContextException: Unable to start web server; nested exception is org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:155) ~[spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:543) ~[spring-context-5.0.4.RELEASE.jar!/:5.0.4.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:140) ~[spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:752) [spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:388) [spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:327) [spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1246) [spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.boot.SpringApplication.run(SpringApplication.java:1234) [spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.tushinov.ServiceRegistryStarter.main(ServiceRegistryStarter.java:11) [classes!/:1.0]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(Unknown Source) ~[na:na]
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Unknown Source) ~[na:na]
at org.springframework.boot.loader.MainMethodRunner.run(MainMethodRunner.java:48) [service-registry-1.0.jar:1.0]
at org.springframework.boot.loader.Launcher.launch(Launcher.java:87) [service-registry-1.0.jar:1.0]
at org.springframework.boot.loader.Launcher.launch(Launcher.java:50) [service-registry-1.0.jar:1.0]
at org.springframework.boot.loader.JarLauncher.main(JarLauncher.java:51) [service-registry-1.0.jar:1.0]
Caused by: org.springframework.boot.web.server.WebServerException: Unable to start embedded Tomcat
at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:125) ~[spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.<init>(TomcatWebServer.java:86) ~[spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getTomcatWebServer(TomcatServletWebServerFactory.java:417) ~[spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.boot.web.embedded.tomcat.TomcatServletWebServerFactory.getWebServer(TomcatServletWebServerFactory.java:176) ~[spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.createWebServer(ServletWebServerApplicationContext.java:179) ~[spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.onRefresh(ServletWebServerApplicationContext.java:152) ~[spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
... 16 common frames omitted
Caused by: java.lang.IllegalStateException: StandardEngine[Tomcat].StandardHost[localhost].TomcatEmbeddedContext[] failed to start
at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.rethrowDeferredStartupExceptions(TomcatWebServer.java:171) ~[spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
at org.springframework.boot.web.embedded.tomcat.TomcatWebServer.initialize(TomcatWebServer.java:110) ~[spring-boot-2.0.0.RELEASE.jar!/:2.0.0.RELEASE]
... 21 common frames omitted
After looking around in Stackoverflow I came across this question but it did not manage to help me with the problem. So I decided to ask a question myself.
I have used mvn clean package for making fat jars for quite some time and never had an issue. How come this time it fails? Im guessing it has something to do with the netflix eureka server. Maybe a missing configuration or something similar.
So here is everything that I currently have:
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>
<groupId>org.tushinov</groupId>
<artifactId>service-registry</artifactId>
<version>1.0</version>
<packaging>jar</packaging>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.0.RELEASE</version>
<relativePath/>
</parent>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/org.springframework.cloud/spring-cloud-starter-netflix-eureka-server -->
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
<version>2.0.0.RELEASE</version>
</dependency>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-devtools</artifactId>
<optional>true</optional>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
</project>
application.properties
spring.application.name=eureka-server
server.port=8761
eureka.client.register-with-eureka=false
eureka.client.fetch-registry=false
and the code
package org.tushinov;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.cloud.netflix.eureka.server.EnableEurekaServer;
#SpringBootApplication
#EnableEurekaServer
public class ServiceRegistryStarter {
public static void main(String[] args) {
SpringApplication.run(ServiceRegistryStarter.class, args);
}
}
If I have missed anything please ask away in the comments for clarification.
Any help and/or suggestion are welcome and greatly appreciated!

After some time I found the answer to this problem. It was not a configuration or anything like it. It was a JDK mistmatch in intelliJ and maven. In intelliJ I was using JDK 1.8 to compile and run my application.
The thing I did not realise was that mvn uses the JAVA_HOME parameter to find which JDK it is supposed to use as opposed to intelliJ where you can specify your jdk. The JAVA_HOME parameter in my case was pointing to JDK 1.9, which, apperantly, might need more dependencies and/or configuration in order to run the Netflix Eureka server.
These resources helped me with solving the problem.

Here is pom which works for me
<?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>
<groupId>com.example.microservices</groupId>
<artifactId>naming-server</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>naming-server</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.1.RELEASE</version>
<relativePath/>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
<spring-cloud.version>Finchley.M9</spring-cloud.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-starter-netflix-eureka-server</artifactId>
</dependency>
</dependencies>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.cloud</groupId>
<artifactId>spring-cloud-dependencies</artifactId>
<version>${spring-cloud.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
</plugin>
</plugins>
</build>
<repositories>
<repository>
<id>spring-milestones</id>
<name>Spring Milestones</name>
<url>https://repo.spring.io/milestone</url>
<snapshots>
<enabled>false</enabled>
</snapshots>
</repository>
</repositories>
</project>

How can I use my own parent.pom instead of the "spring-boot-starter-parent"?

I am new to Spring, Spring boot, and Spring boot starter.
For my different apps I use an own parent.pom for what the have in common. The parent.pom contains the version numbers as properties and dependencies that use the properties as version numbers.
When using my parent.pom maven states that I have to use the "spring-boot-starter-parent".
How can I use my own parent.pom instead of the "spring-boot-starter-parent"?
Meanwhile I changed the pom to this:
<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>
<groupId>com.websystique.springboot</groupId>
<artifactId>SpringBootRestApiExample</artifactId>
<version>1.0.0</version>
<name>SpringBootRestApiExample</name>
<parent>
<groupId>my</groupId>
<artifactId>parent</artifactId>
<version>1.0-SNAPSHOT</version>
<relativePath>../parent/pom.xml</relativePath>
</parent>
<properties>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.1.RELEASE</version>
<type>pom</type>
<scope>import</scope>
</dependency>
<!-- Add typical dependencies for a web application -->
<!-- Adds Tomcat and Spring MVC, along others -->
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-maven-plugin</artifactId>
<version>2.0.1.RELEASE</version>
</plugin>
</plugins>
</build>
</project>
But now I get this warning:
dependencies.dependency.scope' for org.springframework.boot:spring-boot-starter-parent:pom must be one of [provided, compile, runtime, test, system] but is 'import'. # line 27, column 1

You don't have to use spring-boot-starter-parent, it's just that it has an extensive dependencyManagement section that ensures all the Spring Boot dependencies you use in child projects have mutually compatible versions.
I typically declare spring-boot-starter-parent as the parent POM of my parent POM. This way, you get the best of both options.

It is also possible to import the spring-boot-starter-parent pom. So you can use your own pom as parent and you can use the dependency management from the spring boot pom.
...
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>2.0.1.RELEASE</version>
<scope>import</scope>
<type>pom</type>
</dependency>
</dependencies>
</dependencyManagement>
...

ClassNotFoundException while running a Spring Boot application

I am new to Spring boot.I am getting ClassNotFoundException :Spring Application while doing the sample example using spring 1.5.7. I googled for solution and added spring boot maven build plugin.But still the problem not resolved. Please help.
<?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>
<groupId>com.example</groupId>
<artifactId>demo</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>jar</packaging>
<name>demo</name>
<description>Demo project for Spring Boot</description>
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.5.7.RELEASE</version>
<relativePath/> <!-- lookup parent from repository -->
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-web</artifactId>
</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>
Below is my main class
package com.example.demo;
import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
#SpringBootApplication
public class DemoApplication {
public static void main(String[] args) {
SpringApplication.run(DemoApplication.class, args);
}
}
I am getting the below Exception :
Exception in thread "main" java.lang.NoClassDefFoundError: org/springframework/boot/SpringApplication
at com.example.demo.DemoApplication.main(DemoApplication.java:10)
Caused by: java.lang.ClassNotFoundException: org.springframework.boot.SpringApplication
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 1 more

The best way to create a spring boot project from scratch irrespective of build tool (maven, gradle, etc..) is to use https://start.spring.io/ search for your dependencies like (Web, actuator, etc..) and generate the project. Unzip the downloaded project and type the respective command mvn spring-boot:run in your case.

It seems to me that relevant dependencies are not downloaded from maven repo.
Try following command and check if the package compiles okay!
./mvnw clean package

SparkJava Exception java.lang.NoClassDefFoundError: org/eclipse/jetty/websocket/server/pathmap/PathSpec

For Spark-java with code (to be used with Spring Boot)
public static void main(String[] args) {
Spark.port(8080);
Spark.webSocket("/chat", ChatWebSocketHandler.class);
Spark.init();
I get exception and stop
Exception in thread "Thread-2" java.lang.NoClassDefFoundError: org/eclipse/jetty/websocket/server/pathmap/PathSpec
at spark.embeddedserver.jetty.EmbeddedJettyServer.ignite(EmbeddedJettyServer.java:105)
at spark.Service.lambda$init$0(Service.java:349)
at spark.Service$$Lambda$7/1663488386.run(Unknown Source)
at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.ClassNotFoundException: org.eclipse.jetty.websocket.server.pathmap.PathSpec
at java.net.URLClassLoader.findClass(URLClassLoader.java:381)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
... 4 more
With Maven I use
<parent>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-parent</artifactId>
<version>1.4.0.RELEASE</version>
</parent>
<properties>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding>
<java.version>1.8</java.version>
</properties>
<dependencies>
<dependency>
<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-data-mongodb</artifactId>
</dependency>
<dependency>
<groupId>com.sparkjava</groupId>
<artifactId>spark-core</artifactId>
<version>2.5</version>
</dependency>
and I see
jetty-server-9.3.11.v20160721.jar,
websocket-server-9.3.11.v20160721.jar and many others as dependencies
the same works in demo https://github.com/tipsy/spark-websocket

The problem was that Spring Boot has redefined newer Jetty version to be used.
Solved by
<properties>
...
<jetty.version>9.3.6.v20151106</jetty.version> <!-- redefine for sparkjava 2.5 vs 9.3.11.v20160721 in spring-boot-dependencies -->
</properties>