Annotation processor 'org.hibernate.jpamodelgen.JPAMetaModelEntityProcessor' not found

I’m using Gradle Buildship Plugin 3.0 on a OpenJdk 11 project under Eclipse. I can’t generate metamodels. This is my build.gradle

buildscript {
    repositories {
        mavenCentral()
    }
    dependencies {
        classpath("org.springframework.boot:spring-boot-gradle-plugin:2+")
    }
}

apply plugin: 'java'
apply plugin: 'eclipse'
apply plugin: 'idea'
apply plugin: 'org.springframework.boot'
apply plugin: 'io.spring.dependency-management'

bootJar {
    baseName = 'petmenu'
    version =  '0.1.0'
}

repositories {
    mavenCentral()
}

sourceCompatibility = 11
targetCompatibility = 11

dependencies {
    compile("org.springframework.boot:spring-boot-starter-web")

    compile 'org.springframework.boot:spring-boot-starter-data-jpa'

    implementation 'org.mariadb.jdbc:mariadb-java-client'

    testCompile('org.springframework.boot:spring-boot-starter-test')
    
    compile("org.springframework.boot:spring-boot-starter-thymeleaf")
 	
	annotationProcessor('org.hibernate:hibernate-jpamodelgen')
}

sourceSets.main.java.srcDirs += "${buildDir}/generated"

compileJava {
  options.annotationProcessorGeneratedSourcesDirectory = file("${buildDir}/generated")
}

Can you tell me what’s the problem?
I would even know if there’s a real-time support channel, like an irc or gitter room.
Thanks in advance.