private static Constructor getConstructor(PersistentClass persistentClass) {
    if (persistentClass == null || !persistentClass.hasPojoRepresentation()) {
      return null;
    }

    try {
      return ReflectHelper.getDefaultConstructor(persistentClass.getMappedClass());
    } catch (Throwable t) {
      return null;
    }
  }
  public EntityMetamodel(
      PersistentClass persistentClass,
      AbstractEntityPersister persister,
      SessionFactoryImplementor sessionFactory) {
    this.sessionFactory = sessionFactory;
    this.persister = persister;

    name = persistentClass.getEntityName();
    rootName = persistentClass.getRootClass().getEntityName();
    entityType = sessionFactory.getTypeResolver().getTypeFactory().manyToOne(name);

    identifierAttribute =
        PropertyFactory.buildIdentifierAttribute(
            persistentClass, sessionFactory.getIdentifierGenerator(rootName));

    versioned = persistentClass.isVersioned();

    instrumentationMetadata =
        persistentClass.hasPojoRepresentation()
            ? Environment.getBytecodeProvider()
                .getEntityInstrumentationMetadata(persistentClass.getMappedClass())
            : new NonPojoInstrumentationMetadata(persistentClass.getEntityName());

    boolean hasLazy = false;

    propertySpan = persistentClass.getPropertyClosureSpan();
    properties = new NonIdentifierAttribute[propertySpan];
    List<Integer> naturalIdNumbers = new ArrayList<Integer>();
    // temporary ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    propertyNames = new String[propertySpan];
    propertyTypes = new Type[propertySpan];
    propertyUpdateability = new boolean[propertySpan];
    propertyInsertability = new boolean[propertySpan];
    nonlazyPropertyUpdateability = new boolean[propertySpan];
    propertyCheckability = new boolean[propertySpan];
    propertyNullability = new boolean[propertySpan];
    propertyVersionability = new boolean[propertySpan];
    propertyLaziness = new boolean[propertySpan];
    cascadeStyles = new CascadeStyle[propertySpan];
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    // generated value strategies
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
    this.inMemoryValueGenerationStrategies = new InMemoryValueGenerationStrategy[propertySpan];
    this.inDatabaseValueGenerationStrategies = new InDatabaseValueGenerationStrategy[propertySpan];

    boolean foundPreInsertGeneratedValues = false;
    boolean foundPreUpdateGeneratedValues = false;
    boolean foundPostInsertGeneratedValues = false;
    boolean foundPostUpdateGeneratedValues = false;
    // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

    Iterator iter = persistentClass.getPropertyClosureIterator();
    int i = 0;
    int tempVersionProperty = NO_VERSION_INDX;
    boolean foundCascade = false;
    boolean foundCollection = false;
    boolean foundMutable = false;
    boolean foundNonIdentifierPropertyNamedId = false;
    boolean foundInsertGeneratedValue = false;
    boolean foundUpdateGeneratedValue = false;
    boolean foundUpdateableNaturalIdProperty = false;

    while (iter.hasNext()) {
      Property prop = (Property) iter.next();

      if (prop == persistentClass.getVersion()) {
        tempVersionProperty = i;
        properties[i] =
            PropertyFactory.buildVersionProperty(
                persister, sessionFactory, i, prop, instrumentationMetadata.isInstrumented());
      } else {
        properties[i] =
            PropertyFactory.buildEntityBasedAttribute(
                persister, sessionFactory, i, prop, instrumentationMetadata.isInstrumented());
      }

      if (prop.isNaturalIdentifier()) {
        naturalIdNumbers.add(i);
        if (prop.isUpdateable()) {
          foundUpdateableNaturalIdProperty = true;
        }
      }

      if ("id".equals(prop.getName())) {
        foundNonIdentifierPropertyNamedId = true;
      }

      // temporary ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      boolean lazy = prop.isLazy() && instrumentationMetadata.isInstrumented();
      if (lazy) hasLazy = true;
      propertyLaziness[i] = lazy;

      propertyNames[i] = properties[i].getName();
      propertyTypes[i] = properties[i].getType();
      propertyNullability[i] = properties[i].isNullable();
      propertyUpdateability[i] = properties[i].isUpdateable();
      propertyInsertability[i] = properties[i].isInsertable();
      propertyVersionability[i] = properties[i].isVersionable();
      nonlazyPropertyUpdateability[i] = properties[i].isUpdateable() && !lazy;
      propertyCheckability[i] =
          propertyUpdateability[i]
              || (propertyTypes[i].isAssociationType()
                  && ((AssociationType) propertyTypes[i]).isAlwaysDirtyChecked());

      cascadeStyles[i] = properties[i].getCascadeStyle();
      // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

      // generated value strategies
      // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
      GenerationStrategyPair pair = buildGenerationStrategyPair(sessionFactory, prop);
      inMemoryValueGenerationStrategies[i] = pair.getInMemoryStrategy();
      inDatabaseValueGenerationStrategies[i] = pair.getInDatabaseStrategy();

      if (pair.getInMemoryStrategy() != null) {
        final GenerationTiming timing = pair.getInMemoryStrategy().getGenerationTiming();
        if (timing != GenerationTiming.NEVER) {
          final ValueGenerator generator = pair.getInMemoryStrategy().getValueGenerator();
          if (generator != null) {
            // we have some level of generation indicated
            if (timing == GenerationTiming.INSERT) {
              foundPreInsertGeneratedValues = true;
            } else if (timing == GenerationTiming.ALWAYS) {
              foundPreInsertGeneratedValues = true;
              foundPreUpdateGeneratedValues = true;
            }
          }
        }
      }
      if (pair.getInDatabaseStrategy() != null) {
        final GenerationTiming timing = pair.getInDatabaseStrategy().getGenerationTiming();
        if (timing == GenerationTiming.INSERT) {
          foundPostInsertGeneratedValues = true;
        } else if (timing == GenerationTiming.ALWAYS) {
          foundPostInsertGeneratedValues = true;
          foundPostUpdateGeneratedValues = true;
        }
      }
      // ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

      if (properties[i].isLazy()) {
        hasLazy = true;
      }

      if (properties[i].getCascadeStyle() != CascadeStyles.NONE) {
        foundCascade = true;
      }

      if (indicatesCollection(properties[i].getType())) {
        foundCollection = true;
      }

      if (propertyTypes[i].isMutable() && propertyCheckability[i]) {
        foundMutable = true;
      }

      mapPropertyToIndex(prop, i);
      i++;
    }

    if (naturalIdNumbers.size() == 0) {
      naturalIdPropertyNumbers = null;
      hasImmutableNaturalId = false;
      hasCacheableNaturalId = false;
    } else {
      naturalIdPropertyNumbers = ArrayHelper.toIntArray(naturalIdNumbers);
      hasImmutableNaturalId = !foundUpdateableNaturalIdProperty;
      hasCacheableNaturalId = persistentClass.getNaturalIdCacheRegionName() != null;
    }

    this.hasPreInsertGeneratedValues = foundPreInsertGeneratedValues;
    this.hasPreUpdateGeneratedValues = foundPreUpdateGeneratedValues;
    this.hasInsertGeneratedValues = foundPostInsertGeneratedValues;
    this.hasUpdateGeneratedValues = foundPostUpdateGeneratedValues;

    hasCascades = foundCascade;
    hasNonIdentifierPropertyNamedId = foundNonIdentifierPropertyNamedId;
    versionPropertyIndex = tempVersionProperty;
    hasLazyProperties = hasLazy;
    if (hasLazyProperties) LOG.lazyPropertyFetchingAvailable(name);

    lazy =
        persistentClass.isLazy()
            && (
            // TODO: this disables laziness even in non-pojo entity modes:
            !persistentClass.hasPojoRepresentation()
                || !ReflectHelper.isFinalClass(persistentClass.getProxyInterface()));
    mutable = persistentClass.isMutable();
    if (persistentClass.isAbstract() == null) {
      // legacy behavior (with no abstract attribute specified)
      isAbstract =
          persistentClass.hasPojoRepresentation()
              && ReflectHelper.isAbstractClass(persistentClass.getMappedClass());
    } else {
      isAbstract = persistentClass.isAbstract().booleanValue();
      if (!isAbstract
          && persistentClass.hasPojoRepresentation()
          && ReflectHelper.isAbstractClass(persistentClass.getMappedClass())) {
        LOG.entityMappedAsNonAbstract(name);
      }
    }
    selectBeforeUpdate = persistentClass.hasSelectBeforeUpdate();
    dynamicUpdate = persistentClass.useDynamicUpdate();
    dynamicInsert = persistentClass.useDynamicInsert();

    polymorphic = persistentClass.isPolymorphic();
    explicitPolymorphism = persistentClass.isExplicitPolymorphism();
    inherited = persistentClass.isInherited();
    superclass = inherited ? persistentClass.getSuperclass().getEntityName() : null;
    hasSubclasses = persistentClass.hasSubclasses();

    optimisticLockStyle = persistentClass.getOptimisticLockStyle();
    final boolean isAllOrDirty =
        optimisticLockStyle == OptimisticLockStyle.ALL
            || optimisticLockStyle == OptimisticLockStyle.DIRTY;
    if (isAllOrDirty && !dynamicUpdate) {
      throw new MappingException(
          "optimistic-lock=all|dirty requires dynamic-update=\"true\": " + name);
    }
    if (versionPropertyIndex != NO_VERSION_INDX && isAllOrDirty) {
      throw new MappingException(
          "version and optimistic-lock=all|dirty are not a valid combination : " + name);
    }

    hasCollections = foundCollection;
    hasMutableProperties = foundMutable;

    iter = persistentClass.getSubclassIterator();
    while (iter.hasNext()) {
      subclassEntityNames.add(((PersistentClass) iter.next()).getEntityName());
    }
    subclassEntityNames.add(name);

    if (persistentClass.hasPojoRepresentation()) {
      entityNameByInheritenceClassMap.put(
          persistentClass.getMappedClass(), persistentClass.getEntityName());
      iter = persistentClass.getSubclassIterator();
      while (iter.hasNext()) {
        final PersistentClass pc = (PersistentClass) iter.next();
        entityNameByInheritenceClassMap.put(pc.getMappedClass(), pc.getEntityName());
      }
    }

    entityMode = persistentClass.hasPojoRepresentation() ? EntityMode.POJO : EntityMode.MAP;
    final EntityTuplizerFactory entityTuplizerFactory =
        sessionFactory.getSettings().getEntityTuplizerFactory();
    final String tuplizerClassName = persistentClass.getTuplizerImplClassName(entityMode);
    if (tuplizerClassName == null) {
      entityTuplizer =
          entityTuplizerFactory.constructDefaultTuplizer(entityMode, this, persistentClass);
    } else {
      entityTuplizer =
          entityTuplizerFactory.constructTuplizer(tuplizerClassName, this, persistentClass);
    }
  }