entityManager sempre null

Programação Java
,
#1

Erro é porque o entityManager é sempre nulo.

Erro https://gist.github.com/anonymous/8bd13cfaecd896be3b2748f6cb103e76

persistence.xml

<?xml version="1.0" encoding="UTF-8"?>
<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">

    <persistence-unit name="desif" transaction-type="JTA">

        <provider>org.hibernate.jpa.HibernatePersistenceProvider</provider>

         <jta-data-source>java:/desif-ds</jta-data-source>

        <!-- -->
        <class>br.com.netsoft.desif.modelo.desif.ConfiguracaoEntity</class>

        <properties>
            <!-- Configurações específicas do Hibernate -->
            <property name="jboss.entity.validater.jndi.name" value="java:/em" />
            <property name="jboss.entity.manager.factory.jndi.name"
                value="java:/emf/desif" />
            <property name="hibernate.dialect" value="org.hibernate.dialect.PostgreSQLDialect" />
            <property name="hibernate.hbm2ddl.auto" value="update" />
            <property name="hibernate.show_sql" value="true" />
            <property name="hibernate.format_sql" value="true" />
            <property name="show_sql" value="true" />
        </properties>

    </persistence-unit>
</persistence>
#2

Quando inicio o servidor entendo que ele conectar no servidor, pois ele mostra isto no console.

00:13:35,418 INFO  [org.hibernate.tool.hbm2ddl.TableMetadata] (ServerService Thread Pool -- 50) HHH000261: Table found: public.fr_usuario_grupo
00:13:35,418 INFO  [org.hibernate.tool.hbm2ddl.TableMetadata] (ServerService Thread Pool -- 50) HHH000037: Columns: [statusdoregistroid, ip_movimentacao, ts_movimentacao, ugg_id, sis_id, nr_versao, grp_codigo, grp_id, ds_situacao, cd_login_movimentacao, tp_operacao, st_registro, usr_codigo, id]
00:13:35,418 INFO  [org.hibernate.tool.hbm2ddl.TableMetadata] (ServerService Thread Pool -- 50) HHH000108: Foreign keys: [fk_cjrbyne6hfk0miajfgduk5rfr, fr_usuario_grupo_fk2, fr_usuario_grupo_fk, fr_usuario_grupo_fk1]
#3

A maneira como você esta configurando esta errada, pra configurar o banco de dados com spring da para usar annotation(via classes) ou xml, da forma que você configurou funcionaria normalmente no java ee, segue um exemplo de como configurar o banco com xml no spring tirado da própria documentação do framework:

<?xml version="1.0" encoding="UTF-8"?> 

<!-- this is the service object that we want to make transactional -->
<bean id="fooService" class="x.y.service.DefaultFooService"/>

<!-- the transactional advice (what 'happens'; see the <aop:advisor/> bean below) -->
<tx:advice id="txAdvice" transaction-manager="txManager">
    <!-- the transactional semantics... -->
    <tx:attributes>
        <!-- all methods starting with 'get' are read-only -->
        <tx:method name="get*" read-only="true"/>
        <!-- other methods use the default transaction settings (see below) -->
        <tx:method name="*"/>
    </tx:attributes>
</tx:advice>

<!-- ensure that the above transactional advice runs for any execution
    of an operation defined by the FooService interface -->
<aop:config>
    <aop:pointcut id="fooServiceOperation" expression="execution(* x.y.service.FooService.*(..))"/>
    <aop:advisor advice-ref="txAdvice" pointcut-ref="fooServiceOperation"/>
</aop:config>

<!-- don't forget the DataSource -->
<bean id="dataSource" class="org.apache.commons.dbcp.BasicDataSource" destroy-method="close">
    <property name="driverClassName" value="oracle.jdbc.driver.OracleDriver"/>
    <property name="url" value="jdbc:oracle:thin:@rj-t42:1521:elvis"/>
    <property name="username" value="scott"/>
    <property name="password" value="tiger"/>
</bean>

<!-- similarly, don't forget the PlatformTransactionManager -->
<bean id="txManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
    <property name="dataSource" ref="dataSource"/>
</bean>

<!-- other <bean/> definitions here -->

Segue o link também:
https://docs.spring.io/spring/docs/current/spring-framework-reference/data-access.html#spring-data-tier