title: Cannot find the declaration of element 'persistence'
body: <p>I have the following persistence</p>
  
  <p>There is a code snippet:</p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt;
  &lt;persistence version="2.1" xmlns="http://xmlns.jcp.org/xml/ns/persistence" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/persistence http://xmlns.jcp.org/xml/ns/persistence/persistence_2_1.xsd"&gt;
  &lt;persistence-unit name="ProcedimientosAlmacenados"&gt;
      &lt;jta-data-source&gt;java:/jdbc/DesaAppDS&lt;/jta-data-source&gt;
      &lt;properties&gt; 
          &lt;property name="hibernate.show_sql" value="false" /&gt;
          &lt;property name="hibernate.format_sql" value="true" /&gt;
          &lt;property name="hibernate.dialect" value="org.hibernate.dialect.Oracle10gDialect" /&gt;
          &lt;property name="hibernate.hbm2ddl.auto" value="validate" /&gt;
          &lt;property name="hibernate.ejb.entitymanager_factory_name" value="ProcedimientosAlmacenados" /&gt;
          &lt;property name="hibernate.transaction.jta.platform" value="org.hibernate.service.jta.platform.internal.JBossAppServerJtaPlatform" /&gt;
          &lt;property name="hibernate.connection.driver_class" value="oracle.jdbc.driver.OracleDriver"/&gt;
          &lt;property name="openjpa.TransactionMode" value="managed" /&gt;
          &lt;property name="openjpa.ConnectionFactoryMode" value="managed" /&gt;
          &lt;property name="openjpa.jdbc.DBDictionary" value="db2" /&gt;
          &lt;property name="eclipselink.jdbc.batch-writing" value="JDBC"/&gt;
      &lt;/properties&gt;
  &lt;/persistence-unit&gt;
  &lt;/persistence&gt;
  </code></pre>
  
  <p>invoke persistent follows</p>
  
  <pre><code>EntityManagerFactory enfactory = Persistence.createEntityManagerFactory("ProcedimientosAlmacenados");
      EntityManager enmanager = enfactory.createEntityManager();
  </code></pre>
  
  <p>I jump the following error</p>
  
  <pre><code>Caused by: javax.persistence.PersistenceException: Invalid persistence.xml.
  Error parsing XML (line-1 : column -1): cvc-elt.1: Cannot find the declaration of element 'persistence'.
  </code></pre>
  
  <p>Help me please!!!</p>