No Persistence provider for EntityManager named persistence

Question

Hello I need help to solve this problem. When trying to run my java web application on intellij i get the following message:

javax.persistence.PersistenceException: No Persistence provider for EntityManager named persistence

-- src
|-- main
|   |-- java
|   |   `-- service
|   |     `-- dao
|   |         `-- mapping
|   |             |-- 
|   |             |-- 
|   |             `--
|   `-- resources
|       `-- META-INF
|           `-- persistence.xml

here is my persistence.xml file in resources/META-INF/

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0">
<persistence-unit name="persistence">
       <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>
    <mapping-file>Dao/mapping/user.xml</mapping-file>
    <class>Dao.mapping.UserEntity</class>
    <properties>
        <property name="toplink.jdbc.url" value="jdbc:mysql://localhost:3306/test"/>
    <property name="toplink.jdbc.driver" value="com.mysql.jdbc.Driver"/>
    <property name="hibernate.connection.url" value="jdbc:mysql://localhost:3306/test"/>
    <property name="hibernate.connection.driver_class" value="com.mysql.jdbc.Driver"/>
    <property name="openjpa.ConnectionURL" value="jdbc:mysql://localhost:3306/test"/>
    <property name="openjpa.ConnectionDriverName" value="com.mysql.jdbc.Driver"/>
    <property name="eclipselink.jdbc.url" value="jdbc:mysql://localhost:3306/test"/>
    <property name="eclipselink.jdbc.driver" value="com.mysql.jdbc.Driver"/>
</properties>
</persistence-unit>

my gradle build

group 'com.test'
version '1.0-SNAPSHOT'

apply plugin: 'java'
apply plugin: 'war'

sourceCompatibility = 1.5

repositories {
mavenCentral()
}

dependencies {
testCompile group: 'junit', name: 'junit', version: '4.11'
compile group: 'org.hibernate', name: 'hibernate-core', version:          '5.2.4.Final'
compile group: 'mysql', name: 'mysql-connector-java', version: '6.0.5'
compile group: 'org.apache.tomcat', name: 'tomcat-catalina', version: '9.0.0.M13'

compile group: 'org.hibernate', name: 'hibernate-validator', version: '5.3.3.Final'
compile group: 'org.hibernate.javax.persistence', name: 'hibernate-jpa-2.1-api', version: '1.0.0.Final-redhat-1'

}

thank you .

Answer 1

One option is that the error is caused by the referenced entity not existing.

You have "Dao.mapping.UserEntity" in the persistence.xml, but the directory suggests it should be "service.dao.mapping.UserEntity".

A complete stacktrace could help solve the problem.