затмение на проекте знатока предупреждение 'DTD или XML-схемы'

Description Resource    Path    Location    Type
No grammar constraints (DTD or XML schema) detected for the document.   TEST-net.kindleit.gae.example.server.MessageRepositoryTest.xml  /projecttest-gae-example/target/surefire-reports    line 1  XML Problem
No grammar constraints (DTD or XML schema) detected for the document.   appengine-web.xml   /projecttest-gae-example/src/main/webapp/WEB-INF    line 1  XML Problem
No grammar constraints (DTD or XML schema) detected for the document.   appengine-web.xml   /projecttest-gae-example/target/projecttest-gae-example-1.0-SNAPSHOT/WEB-INF    line 1  XML Problem
No grammar constraints (DTD or XML schema) detected for the document.   datastore-indexes-auto.xml  /projecttest-gae-example/WEB-INF/appengine-generated    line 1  XML Problem
No grammar constraints (DTD or XML schema) detected for the document.   jdoconfig.xml   /projecttest-gae-example/src/main/resources/META-INF    line 1  XML Problem
No grammar constraints (DTD or XML schema) detected for the document.   jdoconfig.xml   /projecttest-gae-example/target/projecttest-gae-example-1.0-SNAPSHOT/WEB-INF/classes/META-INF   line 1  XML Problem
No grammar constraints (DTD or XML schema) detected for the document.   webapp-cache.xml    /projecttest-gae-example/target/war/work    line 1  XML Problem

как решить вышеупомянутую проблему на затмении? мой проект является базирующимся знатоком. Это, потому что я пропускаю некоторые файлы даты? как включать его?

пример jdoconfig.xml

<?xml version="1.0" encoding="utf-8"?>
<jdoconfig xmlns="http://java.sun.com/xml/ns/jdo/jdoconfig"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:noNamespaceSchemaLocation="http://java.sun.com/xml/ns/jdo/jdoconfig">

    <persistence-manager-factory name="transactions-optional">
        <property name="javax.jdo.PersistenceManagerFactoryClass"
            value="org.datanucleus.store.appengine.jdo.DatastoreJDOPersistenceManagerFactory"/>
        <property name="javax.jdo.option.ConnectionURL" value="appengine"/>
        <property name="javax.jdo.option.NontransactionalRead" value="true"/>
        <property name="javax.jdo.option.NontransactionalWrite" value="true"/>
        <property name="javax.jdo.option.RetainValues" value="true"/>
        <property name="datanucleus.appengine.autoCreateDatastoreTxns" value="true"/>
    </persistence-manager-factory>
</jdoconfig>