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

Example 1 with Query

use of com.google.appengine.api.datastore.Query in project iosched by google.

the class UpdateRunLogger method getLastRun.

public Entity getLastRun() {
    Query query = new Query(UPDATERUN_ENTITY_KIND).addSort("date", Query.SortDirection.DESCENDING);
    List<Entity> result = datastore.prepare(query).asList(FetchOptions.Builder.withLimit(1));
    if (result == null || result.isEmpty()) {
        return null;
    }
    return result.get(0);
}

Example 2 with Query

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

the class PersistentDataStore method loadMessages.

/**
 * Loads all Message 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<Message> loadMessages() throws PersistentDataStoreException {
    List<Message> messages = new ArrayList<>();
    // Retrieve all messages from the datastore.
    Query query = new Query("chat-messages");
    PreparedQuery results = datastore.prepare(query);
    for (Entity entity : results.asIterable()) {
        try {
            UUID uuid = UUID.fromString((String) entity.getProperty("uuid"));
            UUID conversationUuid = UUID.fromString((String) entity.getProperty("conv_uuid"));
            UUID authorUuid = UUID.fromString((String) entity.getProperty("author_uuid"));
            Instant creationTime = Instant.parse((String) entity.getProperty("creation_time"));
            String content = (String) entity.getProperty("content");
            Message message = new Message(uuid, conversationUuid, authorUuid, content, creationTime);
            messages.add(message);
        } catch (Exception e) {
            // database entity definition mismatches, or service mismatches.
            throw new PersistentDataStoreException(e);
        }
    }
    return messages;
}

Example 3 with Query

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

the class PersistentDataStore method loadConversations.

/**
 * Loads all Conversation 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<Conversation> loadConversations() throws PersistentDataStoreException {
    List<Conversation> conversations = new ArrayList<>();
    // Retrieve all conversations from the datastore.
    Query query = new Query("chat-conversations");
    PreparedQuery results = datastore.prepare(query);
    for (Entity entity : results.asIterable()) {
        try {
            UUID uuid = UUID.fromString((String) entity.getProperty("uuid"));
            UUID ownerUuid = UUID.fromString((String) entity.getProperty("owner_uuid"));
            String title = (String) entity.getProperty("title");
            Instant creationTime = Instant.parse((String) entity.getProperty("creation_time"));
            Conversation conversation = new Conversation(uuid, ownerUuid, title, creationTime);
            conversations.add(conversation);
        } catch (Exception e) {
            // database entity definition mismatches, or service mismatches.
            throw new PersistentDataStoreException(e);
        }
    }
    return conversations;
}

Example 4 with Query

use of com.google.appengine.api.datastore.Query in project java-docs-samples by GoogleCloudPlatform.

the class SignGuestbookServletTest method doPost_userNotLoggedIn.

@Test
public void doPost_userNotLoggedIn() throws Exception {
    servletUnderTest.doPost(mockRequest, mockResponse);
    Query query = new Query("Greeting").setAncestor(new KeyFactory.Builder("Guestbook", "default").getKey());
    PreparedQuery pq = ds.prepare(query);
    // Should only be one at this point.
    Entity greeting = pq.asSingleEntity();
    assertEquals(greeting.getProperty("content"), testPhrase);
}

Example 5 with Query

use of com.google.appengine.api.datastore.Query in project java-docs-samples by GoogleCloudPlatform.

the class GuestbookTestUtilities method cleanDatastore.

public static void cleanDatastore(DatastoreService ds, String book) {
    Query query = new Query("Greeting").setAncestor(new KeyFactory.Builder("Guestbook", book).getKey()).setKeysOnly();
    PreparedQuery pq = ds.prepare(query);
    List<Entity> entities = pq.asList(FetchOptions.Builder.withDefaults());
    ArrayList<Key> keys = new ArrayList<>(entities.size());
    for (Entity e : entities) {
        keys.add(e.getKey());
    }
    ds.delete(keys);
}