Java Code Examples for com.google.cloud.datastore.QueryResults#getCursorAfter()

The following examples show how to use com.google.cloud.datastore.QueryResults#getCursorAfter() . You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.

Example 1

Source File: DatastoreDao.java From getting-started-java with Apache License 2.0

7 votes

@Override
public Result<Book> listBooks(String startCursorString) {
  Cursor startCursor = null;
  if (startCursorString != null && !startCursorString.equals("")) {
    startCursor = Cursor.fromUrlSafe(startCursorString);    // Where we left off
  }
  Query<Entity> query = Query.newEntityQueryBuilder()       // Build the Query
      .setKind("Book5")                                     // We only care about Books
      .setLimit(10)                                         // Only show 10 at a time
      .setStartCursor(startCursor)                          // Where we left off
      .setOrderBy(OrderBy.asc(Book.TITLE))                  // Use default Index "title"
      .build();
  QueryResults<Entity> resultList = datastore.run(query);   // Run the query
  List<Book> resultBooks = entitiesToBooks(resultList);     // Retrieve and convert Entities
  Cursor cursor = resultList.getCursorAfter();              // Where to start next time
  if (cursor != null && resultBooks.size() == 10) {         // Are we paging? Save Cursor
    String cursorString = cursor.toUrlSafe();               // Cursors are WebSafe
    return new Result<>(resultBooks, cursorString);
  } else {
    return new Result<>(resultBooks);
  }
}

Example 2

Source File: DatastoreDao.java From getting-started-java with Apache License 2.0

6 votes

@Override
public Result<Book> listBooksByUser(String userId, String startCursorString) {
  Cursor startCursor = null;
  if (startCursorString != null && !startCursorString.equals("")) {
    startCursor = Cursor.fromUrlSafe(startCursorString);    // Where we left off
  }
  Query<Entity> query = Query.newEntityQueryBuilder()          // Build the Query
      .setKind("Book5")                                        // We only care about Books
      .setFilter(PropertyFilter.eq(Book.CREATED_BY_ID, userId))// Only for this user
      .setLimit(10)                                            // Only show 10 at a time
      .setStartCursor(startCursor)                             // Where we left off
      // a custom datastore index is required since you are filtering by one property
      // but ordering by another
      .setOrderBy(OrderBy.asc(Book.TITLE))
      .build();
  QueryResults<Entity> resultList = datastore.run(query);   // Run the Query
  List<Book> resultBooks = entitiesToBooks(resultList);     // Retrieve and convert Entities
  Cursor cursor = resultList.getCursorAfter();              // Where to start next time
  if (cursor != null && resultBooks.size() == 10) {         // Are we paging? Save Cursor
    String cursorString = cursor.toUrlSafe();               // Cursors are WebSafe
    return new Result<>(resultBooks, cursorString);
  } else {
    return new Result<>(resultBooks);
  }
}

Example 3

Source File: DatastoreDao.java From getting-started-java with Apache License 2.0

6 votes

@Override
public Result<Book> listBooks(String startCursorString) {
  Cursor startCursor = null;
  if (startCursorString != null && !startCursorString.equals("")) {
    startCursor = Cursor.fromUrlSafe(startCursorString);    // Where we left off
  }
  Query<Entity> query = Query.newEntityQueryBuilder()       // Build the Query
      .setKind("Book2")                                     // We only care about Books
      .setLimit(10)                                         // Only show 10 at a time
      .setStartCursor(startCursor)                          // Where we left off
      .setOrderBy(OrderBy.asc(Book.TITLE))                  // Use default Index "title"
      .build();
  QueryResults<Entity> resultList = datastore.run(query);   // Run the query
  List<Book> resultBooks = entitiesToBooks(resultList);     // Retrieve and convert Entities
  Cursor cursor = resultList.getCursorAfter();              // Where to start next time
  if (cursor != null && resultBooks.size() == 10) {         // Are we paging? Save Cursor
    String cursorString = cursor.toUrlSafe();               // Cursors are WebSafe
    return new Result<>(resultBooks, cursorString);
  } else {
    return new Result<>(resultBooks);
  }
}

Example 4

Source File: DatastoreDao.java From getting-started-java with Apache License 2.0

6 votes

@Override
public Result<Book> listBooks(String startCursorString) {
  Cursor startCursor = null;
  if (startCursorString != null && !startCursorString.equals("")) {
    startCursor = Cursor.fromUrlSafe(startCursorString);    // Where we left off
  }
  Query<Entity> query = Query.newEntityQueryBuilder()       // Build the Query
      .setKind("Book3")                                     // We only care about Books
      .setLimit(10)                                         // Only show 10 at a time
      .setStartCursor(startCursor)                          // Where we left off
      .setOrderBy(OrderBy.asc(Book.TITLE))                  // Use default Index "title"
      .build();
  QueryResults<Entity> resultList = datastore.run(query);   // Run the query
  List<Book> resultBooks = entitiesToBooks(resultList);     // Retrieve and convert Entities
  Cursor cursor = resultList.getCursorAfter();              // Where to start next time
  if (cursor != null && resultBooks.size() == 10) {         // Are we paging? Save Cursor
    String cursorString = cursor.toUrlSafe();               // Cursors are WebSafe
    return new Result<>(resultBooks, cursorString);
  } else {
    return new Result<>(resultBooks);
  }
}

Example 5

Source File: DatastoreDao.java From getting-started-java with Apache License 2.0

6 votes

@Override
public Result<Book> listBooks(String startCursorString) {
  Cursor startCursor = null;
  if (startCursorString != null && !startCursorString.equals("")) {
    startCursor = Cursor.fromUrlSafe(startCursorString);    // Where we left off
  }
  Query<Entity> query = Query.newEntityQueryBuilder()       // Build the Query
      .setKind("Book4")                                     // We only care about Books
      .setLimit(10)                                         // Only show 10 at a time
      .setStartCursor(startCursor)                          // Where we left off
      .setOrderBy(OrderBy.asc(Book.TITLE))                  // Use default Index "title"
      .build();
  QueryResults<Entity> resultList = datastore.run(query);   // Run the query
  List<Book> resultBooks = entitiesToBooks(resultList);     // Retrieve and convert Entities
  Cursor cursor = resultList.getCursorAfter();              // Where to start next time
  if (cursor != null && resultBooks.size() == 10) {         // Are we paging? Save Cursor
    String cursorString = cursor.toUrlSafe();               // Cursors are WebSafe
    return new Result<>(resultBooks, cursorString);
  } else {
    return new Result<>(resultBooks);
  }
}

Example 6

Source File: DatastoreDao.java From getting-started-java with Apache License 2.0

6 votes

@Override
public Result<Book> listBooksByUser(String userId, String startCursorString) {
  Cursor startCursor = null;
  if (startCursorString != null && !startCursorString.equals("")) {
    startCursor = Cursor.fromUrlSafe(startCursorString);    // Where we left off
  }
  Query<Entity> query = Query.newEntityQueryBuilder()          // Build the Query
      .setKind("Book4")                                        // We only care about Books
      .setFilter(PropertyFilter.eq(Book.CREATED_BY_ID, userId))// Only for this user
      .setLimit(10)                                            // Only show 10 at a time
      .setStartCursor(startCursor)                             // Where we left off
      // a custom datastore index is required since you are filtering by one property
      // but ordering by another
      .setOrderBy(OrderBy.asc(Book.TITLE))
      .build();
  QueryResults<Entity> resultList = datastore.run(query);   // Run the Query
  List<Book> resultBooks = entitiesToBooks(resultList);     // Retrieve and convert Entities
  Cursor cursor = resultList.getCursorAfter();              // Where to start next time
  if (cursor != null && resultBooks.size() == 10) {         // Are we paging? Save Cursor
    String cursorString = cursor.toUrlSafe();               // Cursors are WebSafe
    return new Result<>(resultBooks, cursorString);
  } else {
    return new Result<>(resultBooks);
  }
}

Example 7

Source File: ConceptsTest.java From java-docs-samples with Apache License 2.0

6 votes

private Cursor cursorPaging(int pageSize, Cursor pageCursor) {
  // [START datastore_cursor_paging]
  EntityQuery.Builder queryBuilder = Query.newEntityQueryBuilder().setKind("Task")
      .setLimit(pageSize);
  if (pageCursor != null) {
    queryBuilder.setStartCursor(pageCursor);
  }
  QueryResults<Entity> tasks = datastore.run(queryBuilder.build());
  while (tasks.hasNext()) {
    Entity task = tasks.next();
    // do something with the task
  }
  Cursor nextPageCursor = tasks.getCursorAfter();
  // [END datastore_cursor_paging]
  return nextPageCursor;
}

Example 8

Source File: DatastoreTemplate.java From spring-cloud-gcp with Apache License 2.0

5 votes

@Override
public <T> DatastoreResultsIterable<?> queryKeysOrEntities(Query query, Class<T> entityClass) {
	QueryResults results = getDatastoreReadWriter().run(query);
	DatastoreResultsIterable resultsIterable;
	if (results.getResultClass() == Key.class) {
		resultsIterable = new DatastoreResultsIterable(results, results.getCursorAfter());
	}
	else {
		resultsIterable = new DatastoreResultsIterable<>(convertEntitiesForRead(results, entityClass),
				results.getCursorAfter());
	}
	maybeEmitEvent(new AfterQueryEvent(resultsIterable, query));
	return resultsIterable;
}

Example 9

Source File: DatastoreTemplate.java From spring-cloud-gcp with Apache License 2.0

5 votes

@Override
public <A, T> DatastoreResultsIterable<T> queryIterable(Query<A> query, Function<A, T> entityFunc) {
	QueryResults<A> results = getDatastoreReadWriter().run(query);
	List resultsList = new ArrayList();
	//cursor is not populated until we iterate
	results.forEachRemaining(e -> {
		resultsList.add(entityFunc.apply(e));
	});
	DatastoreResultsIterable<T> resultsIterable = new DatastoreResultsIterable<>(resultsList,
			results.getCursorAfter());
	maybeEmitEvent(new AfterQueryEvent(resultsIterable, query));
	return resultsIterable;
}

Example 10

Source File: DatastoreTemplate.java From spring-cloud-gcp with Apache License 2.0

5 votes

@Override
public <T> DatastoreResultsCollection<T> findAll(Class<T> entityClass, DatastoreQueryOptions queryOptions) {
	DatastorePersistentEntity<?> persistentEntity = this.datastoreMappingContext.getPersistentEntity(entityClass);
	EntityQuery.Builder builder = Query.newEntityQueryBuilder()
			.setKind(persistentEntity.kindName());
	applyQueryOptions(builder, queryOptions, persistentEntity);
	Query query = builder.build();
	QueryResults queryResults = getDatastoreReadWriter().run(query);
	Collection<T> convertedResults = convertEntitiesForRead(queryResults, entityClass);
	maybeEmitEvent(new AfterQueryEvent(convertedResults, query));
	return new DatastoreResultsCollection<>(convertedResults,
			queryResults != null ? queryResults.getCursorAfter() : null);
}