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The Amazon Web Services SDK for Java provides Java APIs for building software on AWS' cost-effective, scalable, and reliable infrastructure products. The AWS Java SDK allows developers to code against APIs for all of Amazon's infrastructure web services (Amazon S3, Amazon EC2, Amazon SQS, Amazon Relational Database Service, Amazon AutoScaling, etc).

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/*
 * Copyright 2011-2014 Amazon Technologies, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *    http://aws.amazon.com/apache2.0
 *
 * 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.dynamodb.datamodeling;

import java.util.List;

import com.amazonaws.services.dynamodb.AmazonDynamoDB;
import com.amazonaws.services.dynamodb.model.QueryRequest;
import com.amazonaws.services.dynamodb.model.QueryResult;

/**
 * Implementation of the List interface that represents the results from a query
 * in AWS DynamoDB. Paginated results are loaded on demand when the user
 * executes an operation that requires them. Some operations, such as size(),
 * must fetch the entire list, but results are lazily fetched page by page when
 * possible.
 * 
 * This is an unmodifiable list, so callers should not invoke any operations
 * that modify this list, otherwise they will throw an
 * UnsupportedOperationException.
 * 
 * @param 
 *            The type of objects held in this list.
 * @see PaginatedList
 * 
 * @deprecated Use {@link com.amazonaws.services.dynamodbv2.datamodeling.PaginatedQueryList} instead.
 */
@Deprecated
public class PaginatedQueryList extends PaginatedList {

    /** The current query request */
    private final QueryRequest queryRequest;

    /** The current results for the last executed query operation */
    private QueryResult queryResult;


    public PaginatedQueryList(DynamoDBMapper mapper, Class clazz, AmazonDynamoDB dynamo, QueryRequest queryRequest, QueryResult queryResult) {
        super(mapper, clazz, dynamo);

        this.queryRequest = queryRequest;
        this.queryResult  = queryResult;

        allResults.addAll(mapper.marshallIntoObjects(clazz, queryResult.getItems()));
    }

    @Override    
    protected boolean atEndOfResults() {
        return queryResult.getLastEvaluatedKey() == null;
    }

    @Override    
    protected synchronized List fetchNextPage() {
        queryRequest.setExclusiveStartKey(queryResult.getLastEvaluatedKey());
        queryResult = dynamo.query(DynamoDBMapper.applyUserAgent(queryRequest));
        return mapper.marshallIntoObjects(clazz, queryResult.getItems());
    }
}