spring boot 2.1.7 with OpenJpaVendorAdapter

Iam trying to migrate Spring to spring boot application.Now getting an error related to openJpaVenderAdapter.

org.springframework.beans.factory.UnsatisfiedDependencyException: Error creating bean with name 'org.springframework.scheduling.annotation.ProxyAsyncConfiguration': Unsatisfied dependency expressed through method 'setConfigurers' parameter 0; nested exception is org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [org.springframework.orm.jpa.vendor.OpenJpaVendorAdapter] for bean with name 'openJpaVendorAdapter' defined in class path resource [conf/spring/datasource-config.xml]; nested exception is java.lang.ClassNotFoundException: org.springframework.orm.jpa.vendor.OpenJpaVendorAdapter
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:676) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.annotation.InjectionMetadata.inject(InjectionMetadata.java:90) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor.postProcessProperties(AutowiredAnnotationBeanPostProcessor.java:374) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.populateBean(AbstractAutowireCapableBeanFactory.java:1411) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:592) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:199) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:392) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.instantiateUsingFactoryMethod(AbstractAutowireCapableBeanFactory.java:1321) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBeanInstance(AbstractAutowireCapableBeanFactory.java:1160) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.doCreateBean(AbstractAutowireCapableBeanFactory.java:555) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.createBean(AbstractAutowireCapableBeanFactory.java:515) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.lambda$doGetBean$0(AbstractBeanFactory.java:320) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.DefaultSingletonBeanRegistry.getSingleton(DefaultSingletonBeanRegistry.java:222) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doGetBean(AbstractBeanFactory.java:318) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.getBean(AbstractBeanFactory.java:204) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.context.support.PostProcessorRegistrationDelegate.registerBeanPostProcessors(PostProcessorRegistrationDelegate.java:228) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.registerBeanPostProcessors(AbstractApplicationContext.java:721) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.context.support.AbstractApplicationContext.refresh(AbstractApplicationContext.java:534) ~[spring-context-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.boot.web.servlet.context.ServletWebServerApplicationContext.refresh(ServletWebServerApplicationContext.java:141) ~[spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
    at org.springframework.boot.SpringApplication.refresh(SpringApplication.java:743) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
    at org.springframework.boot.SpringApplication.refreshContext(SpringApplication.java:390) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:312) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1214) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
    at org.springframework.boot.SpringApplication.run(SpringApplication.java:1203) [spring-boot-2.1.7.RELEASE.jar:2.1.7.RELEASE]
    at com.ge.hcit.xer.app.services.api.XERServiceMain.main(XERServiceMain.java:20) [classes/:na]
Caused by: org.springframework.beans.factory.CannotLoadBeanClassException: Cannot find class [org.springframework.orm.jpa.vendor.OpenJpaVendorAdapter] for bean with name 'openJpaVendorAdapter' defined in class path resource [conf/spring/datasource-config.xml]; nested exception is java.lang.ClassNotFoundException: org.springframework.orm.jpa.vendor.OpenJpaVendorAdapter
    at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1392) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.determineTargetType(AbstractAutowireCapableBeanFactory.java:680) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractAutowireCapableBeanFactory.predictBeanType(AbstractAutowireCapableBeanFactory.java:647) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.isFactoryBean(AbstractBeanFactory.java:1518) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doGetBeanNamesForType(DefaultListableBeanFactory.java:511) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.getBeanNamesForType(DefaultListableBeanFactory.java:481) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.BeanFactoryUtils.beanNamesForTypeIncludingAncestors(BeanFactoryUtils.java:227) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.findAutowireCandidates(DefaultListableBeanFactory.java:1415) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveMultipleBeans(DefaultListableBeanFactory.java:1322) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.doResolveDependency(DefaultListableBeanFactory.java:1209) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.DefaultListableBeanFactory.resolveDependency(DefaultListableBeanFactory.java:1171) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.annotation.AutowiredAnnotationBeanPostProcessor$AutowiredMethodElement.inject(AutowiredAnnotationBeanPostProcessor.java:668) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    ... 28 common frames omitted
Caused by: java.lang.ClassNotFoundException: org.springframework.orm.jpa.vendor.OpenJpaVendorAdapter
    at java.net.URLClassLoader.findClass(URLClassLoader.java:382) ~[na:1.8.0_202]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:424) ~[na:1.8.0_202]
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:349) ~[na:1.8.0_202]
    at java.lang.ClassLoader.loadClass(ClassLoader.java:357) ~[na:1.8.0_202]
    at java.lang.Class.forName0(Native Method) ~[na:1.8.0_202]
    at java.lang.Class.forName(Class.java:348) ~[na:1.8.0_202]
    at org.springframework.util.ClassUtils.forName(ClassUtils.java:275) ~[spring-core-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanDefinition.resolveBeanClass(AbstractBeanDefinition.java:444) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.doResolveBeanClass(AbstractBeanFactory.java:1457) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    at org.springframework.beans.factory.support.AbstractBeanFactory.resolveBeanClass(AbstractBeanFactory.java:1384) ~[spring-beans-5.1.9.RELEASE.jar:5.1.9.RELEASE]
    ... 39 common frames omitted

I have datasource-config.xml file

<bean id="openJpaVendorAdapter" class="org.springframework.orm.jpa.vendor.OpenJpaVendorAdapter">
    </bean>    
        <bean id="sybaseEntityManagerFactory"
            class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
            <property name="dataSource" ref="sybaseDataSource" />
            <property name="jpaVendorAdapter" ref="openJpaVendorAdapter" />
            <!-- <property name="persistenceUnitName" value="SybaseUnit" /> -->
            <property name="jpaProperties">
                <props>
                    <prop key="javax.persistence.query.timeout">90000</prop>
                </props>
            </property>
            <property name="persistenceUnitName" value="SybaseUnit" />
            <property name="packagesToScan" >
                <list>
                    <value>com.app.datasource.jpa.dto</value>
                </list>
            </property>
          </bean

Porm.xml file

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

        <dependency>
            <groupId>com.sybase.jdbc3.jdbc</groupId>
            <artifactId>jconn3</artifactId>
            <version>${jconn3.version}</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-test</artifactId>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>javax.ws.rs</groupId>
            <artifactId>jsr311-api</artifactId>
            <version>${jsr311-api.version}</version>
        </dependency>

        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>${junit.version}</version>
            <scope>test</scope>
        </dependency>
        <dependency>
            <groupId>com.h2database</groupId>
            <artifactId>h2</artifactId>
            <version>${h2.version}</version>
            <scope>test</scope>
        </dependency>

        <dependency>
            <groupId>org.apache.tomcat</groupId>
            <artifactId>tomcat-jdbc</artifactId>
            <version>9.0.24</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-starter-data-jpa</artifactId>
            <version>2.1.7.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework.boot</groupId>
            <artifactId>spring-boot-autoconfigure</artifactId>
            <version>2.1.7.RELEASE</version>
        </dependency>
    </dependencies>

openJpaVenderAdapter is coming from spring-orm its already available in my project

what is the exact reason for the ClassNotFoundException.did i miss anything or any maven conflict.

The OpenJPA support was removed,

See these issues.

https://github.com/spring-projects/spring-framework/issues/20584

https://github.com/spring-projects/spring-framework/issues/18997

OpenJPA is barely maintained these days and has not caught up with JPA 2.1 in three years (!) ... Even TomEE 7 - as the sole remaining OpenJPA stakeholder - recently went GA without updating OpenJPA either, recommending EclipseLink along the lines of WebSphere 8.5/9.0 instead.

Since the latest OpenJPA 2.4.1 still causes issues in a Java 8 based build, in particular with its Java 6 limited annotation processor, let's remove our dedicated OpenJPA support right away. If it ever gets updated to JPA 2.1 (which is unlikely), it will still work as a standard JPA provider.