Eclipse does not recognize content of persistence.xml

Question

Im getting the following error in eclipse:

The persistence.xml file does not have recognized content.

My persistence.xml file works great in my application but eclipse keeps giving me this error. I got this after moving the file and updating my project configuration with m2eclipse. I did not change the file itself. Anyone knows how to solve this?

persistence.xml:

<?xml version="1.0" encoding="UTF-8"?>
<persistence version="2.0" 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"&gt;
    <persistence-unit name="localDB" transaction-type="RESOURCE_LOCAL">

        <provider>org.apache.openjpa.persistence.PersistenceProviderImpl</provider>
        <class>package.Users</class>
        <properties>
            <!-- enable warnings for debugging -->
            <property name="openjpa.Log" value="DefaultLevel=TRACE, Runtime=INFO, Tool=INFO, SQL=TRACE"/>
            <!-- connection properties -->
            <property name="openjpa.ConnectionURL" value="jdbc:mysql://localhost/test"/>
            <property name="openjpa.ConnectionDriverName" value="com.mysql.jdbc.Driver"/>
            <property name="openjpa.ConnectionUserName" value="root"/>
            <property name="openjpa.ConnectionPassword" value=""/>

        </properties>
    </persistence-unit>
</persistence>

Update

Looks like a bug in m2eclipse in combination with jpa.

https://bugs.eclipse.org/bugs/show_bug.cgi?id=251323

Temporarily solved by setting the option to show it as a warning instead of an error

Answer 1

Whereabouts in your project structure is the file located?

For ref, I have mine in maven-module-name/src/main/resources/META-INF/

Answer 2

Hard to say since hard to reproduce (your persistence.xml is perfectly valid) but maybe try to:

• Clean the project (both an "Project > Clean" and a Maven clean)
• Force Eclipse to validate the XML file again (right-click, and select Validate XML file).

Answer 3

I've had the same problem on a few occasions and what worked for me was to copy the contents of the file, delete it and create a new persistence.xml file and paste the contents back in.

Answer 4

I figured out what the problem is here.... the JPA Facet is assuming that the META-INF folder is directly under a source folder. If you are using a Maven project, you likely have something like src/main/resources or src/test/resources. If your persistence.xml is under these folders it will complain. If you create a new source folder (call it "jpa") and create a META-INF/persistence.xml in there, then it will find it successfully. (I also had to do a clean/close/open project)

This is certainly a pain.... and I can see many situations this won't work well.