Ajuda com integração Spring + JPA

Front-end
#1

Bom dia amigos, estou encontrando dificuldades em integrar o Spring com o JPA, está gerando o clássico erro de NullPointException, e não consigo identificar, uma vez que revisei toda a configuração do applicationContext.xml.

Segue abaixo o conteúdo do arquivo e em seguida a classe:

<bean id="transactionManager" class="org.springframework.orm.jpa.JpaTransactionManager">
        <property name="entityManagerFactory" ref="entityManagerFactory">
        </property>
        <property name="dataSource" ref="dataSource">
        </property>
    </bean>
    <tx:annotation-driven transaction-manager="transactionManager"/>
    
    <bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
        <property name="driverClassName" value="com.mysql.jdbc.Driver">
        </property>
        <property name="url" value="jdbc:mysql://192.168.0.98:3306/noticia">
        </property>
        <property name="username" value="root">
        </property>
        <property name="password" value="root">
        </property>
    </bean>
    
    <bean id="entityManagerFactory" class="org.springframework.orm.jpa.LocalContainerEntityManagerFactoryBean">
        <property name="persistenceUnitName" value="noticia">
        </property>
        <property name="dataSource" ref="dataSource">
        </property>
        <property name="jpaDialect">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaDialect">
            </bean>
        </property>
        <property name="jpaVendorAdapter">
            <bean class="org.springframework.orm.jpa.vendor.HibernateJpaVendorAdapter">
                <property name="database" value="MYSQL">
                </property>
                <property name="showSql" value="true">
                </property>
                <property name="generateDdl" value="true">
                </property>
            </bean>
        </property>
    </bean>
    
    <bean id="loginDao" class="br.persistence.LoginDAO">
        <constructor-arg ref="entityManagerFactory">
        </constructor-arg>
    </bean>

Classe LoginDAO:

package br.persistence;

import javax.persistence.EntityManager;
import javax.persistence.EntityManagerFactory;
import javax.persistence.NoResultException;
import javax.persistence.Query;
import br.entity.Usuario;

public class LoginDAO {

    private EntityManager entityManager;
    private EntityManagerFactory entityManagerFactory;

    public LoginDAO() {
    }

    public LoginDAO(EntityManagerFactory entityManagerFactory) {
        this.entityManagerFactory = entityManagerFactory;
        this.entityManager = this.entityManagerFactory.createEntityManager();
    }

    public Boolean validaLogin(String login, String senha) {
        Query query = this.entityManager.createQuery("SELECT u FROM Usuario u WHERE u.login = :login AND u.senha = :senha");
        query.setParameter("login", login);
        query.setParameter("senha", senha);
        Usuario user = null;
        try {
            user = (Usuario) query.getSingleResult();
        } catch (NoResultException e) {
            e.printStackTrace();
        }
        return (user != null);
    }

    public EntityManager getEntityManager() {
        return entityManager;
    }

    public void setEntityManager(EntityManager entityManager) {
        this.entityManager = entityManager;
    }

    public EntityManagerFactory getEntityManagerFactory() {
        return entityManagerFactory;
    }

    public void setEntityManagerFactory(EntityManagerFactory entityManagerFactory) {
        this.entityManagerFactory = entityManagerFactory;
    }
}

O erro acontece na chamada do método validaLogin.

Agradeço a ajuda.

#2