Examples with DistinctIterable com.mongodb.client.DistinctIterable used on opensource projects

Example 1 with DistinctIterable

use of com.mongodb.client.DistinctIterable in project spring-data-mongodb by spring-projects.

the class MongoTemplate method findDistinct.

/*
	 * (non-Javadoc)
	 * @see org.springframework.data.mongodb.core.MongoOperations#findDistinct(org.springframework.data.mongodb.core.query.Query, java.lang.String, java.lang.String, java.lang.Class, java.lang.Class)
	 */
@Override
@SuppressWarnings("unchecked")
public <T> List<T> findDistinct(Query query, String field, String collectionName, Class<?> entityClass, Class<T> resultClass) {
    Assert.notNull(query, "Query must not be null!");
    Assert.notNull(field, "Field must not be null!");
    Assert.notNull(collectionName, "CollectionName must not be null!");
    Assert.notNull(entityClass, "EntityClass must not be null!");
    Assert.notNull(resultClass, "ResultClass must not be null!");
    MongoPersistentEntity<?> entity = entityClass != Object.class ? getPersistentEntity(entityClass) : null;
    DistinctQueryContext distinctQueryContext = queryOperations.distinctQueryContext(query, field);
    Document mappedQuery = distinctQueryContext.getMappedQuery(entity);
    String mappedFieldName = distinctQueryContext.getMappedFieldName(entity);
    Class<T> mongoDriverCompatibleType = distinctQueryContext.getDriverCompatibleClass(resultClass);
    MongoIterable<?> result = execute(collectionName, (collection) -> {
        if (LOGGER.isDebugEnabled()) {
            LOGGER.debug(String.format("Executing findDistinct using query %s for field: %s in collection: %s", serializeToJsonSafely(mappedQuery), field, collectionName));
        }
        QueryCursorPreparer preparer = new QueryCursorPreparer(query, entityClass);
        if (preparer.hasReadPreference()) {
            collection = collection.withReadPreference(preparer.getReadPreference());
        }
        DistinctIterable<T> iterable = collection.distinct(mappedFieldName, mappedQuery, mongoDriverCompatibleType);
        distinctQueryContext.applyCollation(entityClass, iterable::collation);
        return iterable;
    });
    if (resultClass == Object.class || mongoDriverCompatibleType != resultClass) {
        MongoConverter converter = getConverter();
        DefaultDbRefResolver dbRefResolver = new DefaultDbRefResolver(mongoDbFactory);
        result = result.map((source) -> converter.mapValueToTargetType(source, distinctQueryContext.getMostSpecificConversionTargetType(resultClass, entityClass), dbRefResolver));
    }
    try {
        return (List<T>) result.into(new ArrayList<>());
    } catch (RuntimeException e) {
        throw potentiallyConvertRuntimeException(e, exceptionTranslator);
    }
}