How to use javax.persistence.spi

@Override
public String getProviderClassName() {
  return persistenceUnitInfo.getPersistenceProviderClassName();
}

@Override
public Object getNonJtaDataSource() {
  return persistenceUnitInfo.getNonJtaDataSource();
}

@Override
public boolean isExcludeUnlistedClasses() {
  return persistenceUnitInfo.excludeUnlistedClasses();
}

private static List<PersistenceProvider> getProviders() {
  return PersistenceProviderResolverHolder
      .getPersistenceProviderResolver()
      .getPersistenceProviders();
}

@Override
public DataSource getDataSource() {
  if (this.persistenceUnitInfo != null) {
    return (this.persistenceUnitInfo.getJtaDataSource() != null ?
        this.persistenceUnitInfo.getJtaDataSource() :
        this.persistenceUnitInfo.getNonJtaDataSource());
  }
  return (this.internalPersistenceUnitManager.getDefaultJtaDataSource() != null ?
      this.internalPersistenceUnitManager.getDefaultJtaDataSource() :
      this.internalPersistenceUnitManager.getDefaultDataSource());
}

@Override
public String getName() {
  return persistenceUnitInfo.getPersistenceUnitName();
}

  public boolean isLoaded(Object object) {
    List<PersistenceProvider> providers = Persistence.getProviders();
    for ( PersistenceProvider provider : providers ) {
      final LoadState state = provider.getProviderUtil().isLoaded( object );
      if ( state == LoadState.UNKNOWN ) continue;
      return state == LoadState.LOADED;
    }
    return true;
  }
};

@Override
public List<String> getManagedClassNames() {
  return persistenceUnitInfo.getManagedClassNames();
}

@Override
public Properties getProperties() {
  return persistenceUnitInfo.getProperties();
}

@Override
public Object getJtaDataSource() {
  return persistenceUnitInfo.getJtaDataSource();
}

@Override
public ClassLoader getClassLoader() {
  return persistenceUnitInfo.getClassLoader();
}

@Override
public List<URL> getJarFileUrls() {
  return persistenceUnitInfo.getJarFileUrls();
}

@Override
public PersistenceUnitTransactionType getTransactionType() {
  return persistenceUnitInfo.getTransactionType();
}

@Override
public List<String> getMappingFileNames() {
  return persistenceUnitInfo.getMappingFileNames();
}

@Override
public URL getPersistenceUnitRootUrl() {
  return persistenceUnitInfo.getPersistenceUnitRootUrl();
}

@Override
public ClassLoader getTempClassLoader() {
  return persistenceUnitInfo.getNewTempClassLoader();
}

@Override
public ValidationMode getValidationMode() {
  return persistenceUnitInfo.getValidationMode();
}

@Override
public SharedCacheMode getSharedCacheMode() {
  return persistenceUnitInfo.getSharedCacheMode();
}

@Override
@Nullable
public String getPersistenceUnitName() {
  if (this.persistenceUnitInfo != null) {
    return this.persistenceUnitInfo.getPersistenceUnitName();
  }
  return super.getPersistenceUnitName();
}

@Override
public Map<String, Object> getJpaPropertyMap(PersistenceUnitInfo pui) {
  return buildJpaPropertyMap(this.jpaDialect.prepareConnection &&
      pui.getTransactionType() != PersistenceUnitTransactionType.JTA);
}