Class “model.Address” is listed in the persistence.xml file but not mapped

问题

I have created a JPA project. In that Eclipse displays the following error on the entity class.

Class "model.Address" is listed in the persistence.xml file but not mapped

How am I supposed to map the entity class in persistance.xml?

Here is the model.Address entity:

package model;

import java.io.Serializable;

import javax.persistence.*;

@Entity
public class Address implements Serializable {

    @Id
    @GeneratedValue(strategy = GenerationType.SEQUENCE)
    private long id;
    private String city;
    private String country;
    private String province;
    private String postalCode;
    private String street;

    // Getters/setters omitted for brevity.
}

Here is the persistence.xml:

<?xml version="1.0" encoding="UTF-8" ?>
<persistence 
    xmlns="http://java.sun.com/xml/ns/persistence"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/persistence http://java.sun.com/xml/ns/persistence/persistence_2_0.xsd"
    version="2.0" 
>
    <provider>org.eclipse.persistance.example.jpa.20.employee.annotations</provider>

    <persistence-unit name="employee" transaction-type="RESOURCE_LOCAL">
        <class>model.Employee</class>
        <class>model.Address</class>

        <properties>
            <property name="javax.persistence.jdbc.driver" value="oracle.jdbc.OracleDriver" />
            <property name="javax.persistence.jdbc.url" value="jdbc:oracle:thin:@localhost:1521:orcl" />
            <property name="javax.persistence.jdbc.user" value="scott" />
            <property name="javax.persistence.jdbc.password" value="tiger" />
        </properties>
    </persistence-unit>
</persistence>

回答1:

This is an Eclipse quirk. I recently had exactly this problem when I created a new JPA project with the JPA library configuration disabled, but didn't manually configure the JPA libraries before I created the entities by the Eclipse New JPA Entity wizard. After creating the entities I configured the JPA libraries in project's Build Path (just by adding target Java EE server runtime in Libraries), but the validation error still remains. I could solve it in at least one of following ways:

1. Rightclick persistence.xml file, JPA Tools -> Synchronize Class List.
2. Or, rightclick project, Validate.
3. Or, close/reopen project.

This is consistently reproducible. I was using Eclipse Indigo SR1. When I create the entities after configuring the JPA libraries, this validation error doesn't occur.

回答2:

Right click on jpa project

then

回答3:

I think you have the wrong JPA provider class. It has to be:

<provider>org.eclipse.persistence.jpa.PersistenceProvider</provider>

(the one you've set doesn't seem to be a class at all, let alone a provider class)

回答4:

Make sure your class is annotated with @Entity (from javax.persistence.Entity)

I realise that's not the OP's problem, but I got caught by that and Google sent me here.

回答5:

You need to create a persistence file and a ORM mapping file for JPA, refer the mapping file from persistence file.

<persistence-unit name="persistenceUnit"
    transaction-type="RESOURCE_LOCAL">
    <provider>org.datanucleus.api.jpa.PersistenceProviderImpl</provider>
    <mapping-file>META-INF/hbase-orm.xml</mapping-file>
    <class>com.xxx.logcollector.entity.DefaultLogableEntity</class>
    <properties>
        <property name="datanucleus.jpa.addClassTransformer" value="false" />
        <property name="datanucleus.managedRuntime" value="false" />

....

Create ORM mapping file

<entity-mappings xmlns="http://java.sun.com/xml/ns/persistence/orm"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://java.sun.com/xml/ns/persistence/orm http://java.sun.com/xml/ns/persistence/orm_1_0.xsd"
    version="1.0">
    <entity class="com.xxx.cne.logcollector.entity.DefaultLogableEntity"
        name="DefaultLogableEntity">
        <table name="RAW_LOG_COLLECTION" />
        <attributes>
            <id name="clientHostIP">
                <column name="ANALYTICS:CLIENT_IP" />
            </id>
            <basic name="requestDateTime">
                <column name="ANALYTICS:REQUEST_DATETIME" />
            </basic>

...

Create entity manager in spring

<bean id="entityManagerFactory"
    class="org.springframework.orm.jpa.LocalEntityManagerFactoryBean">
    <property name="persistenceUnitName" value="persistenceUnit"></property>

回答6:

If eclipse is used , go to Window>Preference>Validation and uncheck Suspend all validators option .Clean the project and problem get solved.

回答7:

Any of the above didnt work.

For anyone who is searching for the "Class xxxx is mapped, but is not included in any persistence unit" error in Eclipse or RAD:

1. Right-click on the project and choose properties.
2. Select JPA
3. Select the radio button "Discover annotated classes automatically"
4. OK and wait for the project to finish building.

These steps worked for me.

回答8:

It should be written like:

@Entity
**@Table(name="Address",schema="ABCD")** `

...or it could be written like :

@Entity
public class Address {

} 

回答9:

i got similar error and when eclipse artifacts folder ".settings" is missed . After i generate eclipse artifacts using "maven-eclipse-plugin" , the error is gone

来源：https://stackoverflow.com/questions/2242637/class-model-address-is-listed-in-the-persistence-xml-file-but-not-mapped