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/*
* Copyright 2014-2021 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Licensed under the Apache License, Version 2.0 (the "License").
* You may not use this file except in compliance with the License.
* A copy of the License is located at
*
* http://aws.amazon.com/apache2.0
*
* or in the "license" file accompanying this file. This file is distributed
* on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
* express or implied. See the License for the specific language governing
* permissions and limitations under the License.
*/
package com.amazonaws.services.dynamodbv2.document;
import com.amazonaws.services.dynamodbv2.document.internal.PageBasedCollection;
import com.amazonaws.services.dynamodbv2.document.internal.PageIterable;
/**
* A collection of Table's (initialized with the respective table
* names).
*
* An TableCollection object maintains a cursor pointing to its
* current pages of data. Initially the cursor is positioned before the first
* page. The next method moves the cursor to the next row, and because it
* returns false when there are no more rows in the TableCollection
* object, it can be used in a while loop to iterate through the collection.
*
* Network calls can be triggered when the collection is iterated across page
* boundaries.
*
* @param low level result type
*/
public abstract class TableCollection extends PageBasedCollection {
// Overriding these just so javadocs will show up.
/**
* Returns an {@code Iterable>} that iterates over pages of
* tables from this collection. Each call to {@code Iterator.next} on an
* {@code Iterator} returned from this {@code Iterable} results in exactly
* one call to DynamoDB to retrieve a single page of results.
*
*
* TableCollection<?> collection = ...;
* for (Page<Table> page : collection.pages()) {
* processTables(page);
* }
*
*
* The use of the internal/undocumented {@code PageIterable} class instead
* of {@code Iterable} in the public interface here is retained for
* backwards compatibility. It doesn't expose any methods beyond those
* of the {@code Iterable} interface. This method will be changed to return
* an {@code Iterable>} directly in a future release of the
* SDK.
*
* @see Page
*/
@Override
public PageIterable pages() {
return super.pages();
}
/**
* Returns the maximum number of resources to be retrieved in this
* collection; or null if there is no limit.
*/
@Override
public abstract Integer getMaxResultSize();
/**
* Returns the low-level result last retrieved (for the current page) from
* the server side; or null if there has yet no calls to the server.
*/
@Override
public R getLastLowLevelResult() {
return super.getLastLowLevelResult();
}
/**
* Used to register a listener for the event of receiving a low-level result
* from the server side.
*
* @param listener
* listener to be registered. If null, a "none" listener will be
* set.
* @return the previously registered listener. The return value is never
* null.
*/
@Override
public LowLevelResultListener registerLowLevelResultListener(
LowLevelResultListener listener) {
return super.registerLowLevelResultListener(listener);
}
}