/* * Copyright 2014-2015 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.codesamples.document; import java.text.SimpleDateFormat; import java.util.Date; import java.util.Iterator; import com.amazonaws.auth.profile.ProfileCredentialsProvider; import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient; import com.amazonaws.services.dynamodbv2.document.DynamoDB; import com.amazonaws.services.dynamodbv2.document.Item; import com.amazonaws.services.dynamodbv2.document.ItemCollection; import com.amazonaws.services.dynamodbv2.document.Page; import com.amazonaws.services.dynamodbv2.document.QueryOutcome; import com.amazonaws.services.dynamodbv2.document.Table; import com.amazonaws.services.dynamodbv2.document.spec.QuerySpec; import com.amazonaws.services.dynamodbv2.document.utils.ValueMap; public class DocumentAPIQuery { static DynamoDB dynamoDB = new DynamoDB(new AmazonDynamoDBClient(new ProfileCredentialsProvider())); static String tableName = "Reply"; public static void main(String[] args) throws Exception { String forumName = "Amazon DynamoDB"; String threadSubject = "DynamoDB Thread 1"; findRepliesForAThread(forumName, threadSubject); findRepliesForAThreadSpecifyOptionalLimit(forumName, threadSubject); findRepliesInLast15DaysWithConfig(forumName, threadSubject); findRepliesPostedWithinTimePeriod(forumName, threadSubject); findRepliesUsingAFilterExpression(forumName, threadSubject); } private static void findRepliesForAThread(String forumName, String threadSubject) { Table table = dynamoDB.getTable(tableName); String replyId = forumName + "#" + threadSubject; QuerySpec spec = new QuerySpec() .withKeyConditionExpression("Id = :v_id") .withValueMap(new ValueMap() .withString(":v_id", replyId)); ItemCollection<QueryOutcome> items = table.query(spec); System.out.println("\nfindRepliesForAThread results:"); Iterator<Item> iterator = items.iterator(); while (iterator.hasNext()) { System.out.println(iterator.next().toJSONPretty()); } } private static void findRepliesForAThreadSpecifyOptionalLimit(String forumName, String threadSubject) { Table table = dynamoDB.getTable(tableName); String replyId = forumName + "#" + threadSubject; QuerySpec spec = new QuerySpec() .withKeyConditionExpression("Id = :v_id") .withValueMap(new ValueMap() .withString(":v_id", replyId)) .withMaxPageSize(1); ItemCollection<QueryOutcome> items = table.query(spec); System.out.println("\nfindRepliesForAThreadSpecifyOptionalLimit results:"); // Process each page of results int pageNum = 0; for (Page<Item, QueryOutcome> page : items.pages()) { System.out.println("\nPage: " + ++pageNum); // Process each item on the current page Iterator<Item> item = page.iterator(); while (item.hasNext()) { System.out.println(item.next().toJSONPretty()); } } } private static void findRepliesInLast15DaysWithConfig(String forumName, String threadSubject) { Table table = dynamoDB.getTable(tableName); long twoWeeksAgoMilli = (new Date()).getTime() - (15L*24L*60L*60L*1000L); Date twoWeeksAgo = new Date(); twoWeeksAgo.setTime(twoWeeksAgoMilli); SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"); String twoWeeksAgoStr = df.format(twoWeeksAgo); String replyId = forumName + "#" + threadSubject; QuerySpec spec = new QuerySpec() .withProjectionExpression("Message, ReplyDateTime, PostedBy") .withKeyConditionExpression("Id = :v_id and ReplyDateTime <= :v_reply_dt_tm") .withValueMap(new ValueMap() .withString(":v_id", replyId) .withString(":v_reply_dt_tm", twoWeeksAgoStr)); ItemCollection<QueryOutcome> items = table.query(spec); System.out.println("\nfindRepliesInLast15DaysWithConfig results:"); Iterator<Item> iterator = items.iterator(); while (iterator.hasNext()) { System.out.println(iterator.next().toJSONPretty()); } } private static void findRepliesPostedWithinTimePeriod(String forumName, String threadSubject) { Table table = dynamoDB.getTable(tableName); long startDateMilli = (new Date()).getTime() - (15L*24L*60L*60L*1000L); long endDateMilli = (new Date()).getTime() - (5L*24L*60L*60L*1000L); java.text.SimpleDateFormat df = new java.text.SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'"); String startDate = df.format(startDateMilli); String endDate = df.format(endDateMilli); String replyId = forumName + "#" + threadSubject; QuerySpec spec = new QuerySpec() .withProjectionExpression("Message, ReplyDateTime, PostedBy") .withKeyConditionExpression("Id = :v_id and ReplyDateTime between :v_start_dt and :v_end_dt") .withValueMap(new ValueMap() .withString(":v_id", replyId) .withString(":v_start_dt", startDate) .withString(":v_end_dt", endDate)); ItemCollection<QueryOutcome> items = table.query(spec); System.out.println("\nfindRepliesPostedWithinTimePeriod results:"); Iterator<Item> iterator = items.iterator(); while (iterator.hasNext()) { System.out.println(iterator.next().toJSONPretty()); } } private static void findRepliesUsingAFilterExpression(String forumName, String threadSubject) { Table table = dynamoDB.getTable(tableName); String replyId = forumName + "#" + threadSubject; QuerySpec spec = new QuerySpec() .withProjectionExpression("Message, ReplyDateTime, PostedBy") .withKeyConditionExpression("Id = :v_id") .withFilterExpression("PostedBy = :v_postedby") .withValueMap(new ValueMap() .withString(":v_id", replyId) .withString(":v_postedby", "User B")); ItemCollection<QueryOutcome> items = table.query(spec); System.out.println("\nfindRepliesUsingAFilterExpression results:"); Iterator<Item> iterator = items.iterator(); while (iterator.hasNext()) { System.out.println(iterator.next().toJSONPretty()); } } }