Examples with Query com.google.appengine.api.datastore.Query used on opensource projects

Example 66 with Query

use of com.google.appengine.api.datastore.Query in project CodeU-Spring-2018 by jwang281.

the class PersistentDataStore method loadUsers.

/**
 * Loads all User objects from the Datastore service and returns them in a List.
 *
 * @throws PersistentDataStoreException if an error was detected during the load from the
 *     Datastore service
 */
public List<User> loadUsers() throws PersistentDataStoreException {
    List<User> users = new ArrayList<>();
    // Retrieve all users from the datastore.
    Query query = new Query("chat-users");
    PreparedQuery results = datastore.prepare(query);
    for (Entity entity : results.asIterable()) {
        try {
            UUID uuid = UUID.fromString((String) entity.getProperty("uuid"));
            String userName = (String) entity.getProperty("username");
            String password = (String) entity.getProperty("password");
            Instant creationTime = Instant.parse((String) entity.getProperty("creation_time"));
            User user = new User(uuid, userName, password, creationTime);
            users.add(user);
        } catch (Exception e) {
            // database entity definition mismatches, or service mismatches.
            throw new PersistentDataStoreException(e);
        }
    }
    return users;
}

Example 67 with Query

use of com.google.appengine.api.datastore.Query in project Cached-Datastore by Emperorlou.

the class CachedDatastoreService method fetchAsList.

public List<CachedEntity> fetchAsList(String kind, Filter filter, int limit) {
    Query q = new Query(kind);
    q.setFilter(filter);
    return fetchAsList(q, limit);
}

Example 68 with Query

use of com.google.appengine.api.datastore.Query in project Cached-Datastore by Emperorlou.

the class CachedDatastoreService method fetchAsList.

public List<CachedEntity> fetchAsList(String kind, Filter filter, int limit, Cursor startEntityCursor) {
    Query q = new Query(kind);
    q.setFilter(filter);
    List<Key> keys = fetchKeys(q, limit, startEntityCursor);
    return fetchEntitiesFromKeys(keys);
}

Example 69 with Query

use of com.google.appengine.api.datastore.Query in project Cached-Datastore by Emperorlou.

the class QueryHelper method getFilteredList_Count.

public Long getFilteredList_Count(String kind, Integer limit, String fieldName, FilterOperator operator, Object equalToValue, String fieldName2, FilterOperator operator2, Object equalToValue2, String fieldName3, FilterOperator operator3, Object equalToValue3) {
    Query q = new Query(kind);
    FilterPredicate f1 = new FilterPredicate(fieldName, operator, equalToValue);
    FilterPredicate f2 = new FilterPredicate(fieldName2, operator2, equalToValue2);
    FilterPredicate f3 = new FilterPredicate(fieldName3, operator3, equalToValue3);
    Filter f = CompositeFilterOperator.and(f1, f2, f3);
    q.setFilter(f);
    return ds.countEntities(q, 5000);
}

Example 70 with Query

use of com.google.appengine.api.datastore.Query in project Cached-Datastore by Emperorlou.

the class ShardedCounterService method resetCounter.

/**
 * This method is used to reset the counter back to 0. It deletes all shards.
 *
 * @param entity
 * @param key
 */
public void resetCounter(Key entityKey, String fieldName) {
    Query query = new Query(SHARD_COUNTER_KIND);
    query.setFilter(getShardQueryFilterFor(entityKey, fieldName));
    query.setKeysOnly();
    List<Key> keys = new ArrayList<>();
    for (CachedEntity en : ds.fetchAsIterable(query)) {
        keys.add(en.getKey());
    }
    ds.delete(keys);
}