javax.persistence.metamodel.ManagedType#getSingularAttributes ( )源码实例Demo

public <T> List<Predicate> byExample(ManagedType<T> mt, Path<T> mtPath, T mtValue, SearchParameters sp, CriteriaBuilder builder) {
    List<Predicate> predicates = newArrayList();
    for (SingularAttribute<? super T, ?> attr : mt.getSingularAttributes()) {
        if (attr.getPersistentAttributeType() == MANY_TO_ONE //
                || attr.getPersistentAttributeType() == ONE_TO_ONE //
                || attr.getPersistentAttributeType() == EMBEDDED) {
            continue;
        }

        Object attrValue = jpaUtil.getValue(mtValue, attr);
        if (attrValue != null) {
            if (attr.getJavaType() == String.class) {
                if (isNotEmpty((String) attrValue)) {
                    predicates.add(jpaUtil.stringPredicate(mtPath.get(jpaUtil.stringAttribute(mt, attr)), attrValue, sp, builder));
                }
            } else {
                predicates.add(builder.equal(mtPath.get(jpaUtil.attribute(mt, attr)), attrValue));
            }
        }
    }
    return predicates;
}
 

@SuppressWarnings("unchecked")
public <T extends Identifiable<?>, M2O extends Identifiable<?>> List<Predicate> byExampleOnXToOne(ManagedType<T> mt, Root<T> mtPath, T mtValue,
                                                                                                  SearchParameters sp, CriteriaBuilder builder) {
    List<Predicate> predicates = newArrayList();
    for (SingularAttribute<? super T, ?> attr : mt.getSingularAttributes()) {
        if (attr.getPersistentAttributeType() == MANY_TO_ONE || attr.getPersistentAttributeType() == ONE_TO_ONE) {
            M2O m2oValue = (M2O) jpaUtil.getValue(mtValue, mt.getAttribute(attr.getName()));
            Class<M2O> m2oType = (Class<M2O>) attr.getBindableJavaType();
            Path<M2O> m2oPath = (Path<M2O>) mtPath.get(attr);
            ManagedType<M2O> m2oMt = em.getMetamodel().entity(m2oType);
            if (m2oValue != null) {
                if (m2oValue.isIdSet()) { // we have an id, let's restrict only on this field
                    predicates.add(builder.equal(m2oPath.get("id"), m2oValue.getId()));
                } else {
                    predicates.addAll(byExample(m2oMt, m2oPath, m2oValue, sp, builder));
                }
            }
        }
    }
    return predicates;
}
 

public <T> List<Predicate> byExample(ManagedType<T> mt, Path<T> mtPath, T mtValue, SearchParameters sp, CriteriaBuilder builder) {
    List<Predicate> predicates = newArrayList();
    for (SingularAttribute<? super T, ?> attr : mt.getSingularAttributes()) {
        if (!isPrimaryKey(mt, attr)) {
            continue;
        }

        Object attrValue = jpaUtil.getValue(mtValue, attr);
        if (attrValue != null) {
            predicates.add(builder.equal(mtPath.get(jpaUtil.attribute(mt, attr)), attrValue));
        }
    }
    return predicates;
}
 

/**
    * Returns the property name on the given entity type which the given database column is mapped to.
    *
    * <p>
    * If no field on the given type is mapped to this field (which is common in cases of a JPA relationship without an
    * actual {@link javax.persistence.Column} annotated field to represent the foreign key) then this method will
    * return null.
    * </p>
    *
    * @param entityType the entity type on which to search for a property that is mapped to the given column
    * @param databaseColumnName the name of the database column
    *
    * @return the name of the property on the given entity type which maps to the given column, or null if no such
    *         mapping exists
    */
@SuppressWarnings({ "unchecked", "rawtypes" })
   protected String getPropertyNameFromDatabaseColumnName(ManagedType entityType, String databaseColumnName) {
	for (SingularAttributeImpl attr : (Set<SingularAttributeImpl>) entityType.getSingularAttributes()) {
		if (!attr.isAssociation()) {
			if (!(attr.getClass().isAssignableFrom(EmbeddableTypeImpl.class)) &&
                       !(attr.getMapping().getClass().isAssignableFrom(AggregateObjectMapping.class)) &&
                       attr.getMapping().getField().getName().equals(databaseColumnName)) {
				return attr.getName();
			}
		}
	}
	return null;
}