/*
* 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.datamodeling;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.List;
import java.util.Set;
import java.util.TimeZone;
import com.amazonaws.auth.profile.ProfileCredentialsProvider;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBAttribute;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBHashKey;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBMapper;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBQueryExpression;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBRangeKey;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBScanExpression;
import com.amazonaws.services.dynamodbv2.datamodeling.DynamoDBTable;
import com.amazonaws.services.dynamodbv2.model.AttributeValue;
import com.amazonaws.services.dynamodbv2.model.ComparisonOperator;
import com.amazonaws.services.dynamodbv2.model.Condition;
public class ObjectPersistenceQueryScanExample {
static AmazonDynamoDBClient client = new AmazonDynamoDBClient(new ProfileCredentialsProvider());
public static void main(String[] args) throws Exception {
try {
DynamoDBMapper mapper = new DynamoDBMapper(client);
// Get a book - Id=101
GetBook(mapper, 101);
// Sample forum and thread to test queries.
String forumName = "Amazon DynamoDB";
String threadSubject = "DynamoDB Thread 1";
// Sample queries.
FindRepliesInLast15Days(mapper, forumName, threadSubject);
FindRepliesPostedWithinTimePeriod(mapper, forumName, threadSubject);
// Scan a table and find book items priced less than specified value.
FindBooksPricedLessThanSpecifiedValue(mapper, "20");
// Scan a table with multiple threads and find bicycle items with a specified bicycle type
int numberOfThreads = 16;
FindBicyclesOfSpecificTypeWithMultipleThreads(mapper, numberOfThreads, "Road");
System.out.println("Example complete!");
} catch (Throwable t) {
System.err.println("Error running the ObjectPersistenceQueryScanExample: " + t);
t.printStackTrace();
}
}
private static void GetBook(DynamoDBMapper mapper, int id) throws Exception {
System.out.println("GetBook: Get book Id='101' ");
System.out.println("Book table has no range key attribute, so you Get (but no query).");
Book book = mapper.load(Book.class, 101);
System.out.format("Id = %s Title = %s, ISBN = %s %n", book.getId(), book.getTitle(), book.getISBN() );
}
private static void FindRepliesInLast15Days(DynamoDBMapper mapper,
String forumName,
String threadSubject) throws Exception {
System.out.println("FindRepliesInLast15Days: Replies within last 15 days.");
String hashKey = forumName + "#" + threadSubject;
long twoWeeksAgoMilli = (new Date()).getTime() - (15L*24L*60L*60L*1000L);
Date twoWeeksAgo = new Date();
twoWeeksAgo.setTime(twoWeeksAgoMilli);
SimpleDateFormat dateFormatter = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
dateFormatter.setTimeZone(TimeZone.getTimeZone("UTC"));
String twoWeeksAgoStr = dateFormatter.format(twoWeeksAgo);
Condition rangeKeyCondition = new Condition()
.withComparisonOperator(ComparisonOperator.GT.toString())
.withAttributeValueList(new AttributeValue().withS(twoWeeksAgoStr.toString()));
Reply replyKey = new Reply();
replyKey.setId(hashKey);
DynamoDBQueryExpression<Reply> queryExpression = new DynamoDBQueryExpression<Reply>()
.withHashKeyValues(replyKey)
.withRangeKeyCondition("ReplyDateTime", rangeKeyCondition);
List<Reply> latestReplies = mapper.query(Reply.class, queryExpression);
for (Reply reply : latestReplies) {
System.out.format("Id=%s, Message=%s, PostedBy=%s %n, ReplyDateTime=%s %n",
reply.getId(), reply.getMessage(), reply.getPostedBy(), reply.getReplyDateTime() );
}
}
private static void FindRepliesPostedWithinTimePeriod(
DynamoDBMapper mapper,
String forumName,
String threadSubject) throws Exception {
String hashKey = forumName + "#" + threadSubject;
System.out.println("FindRepliesPostedWithinTimePeriod: Find replies for thread Message = 'DynamoDB Thread 2' posted within a period.");
long startDateMilli = (new Date()).getTime() - (14L*24L*60L*60L*1000L); // Two weeks ago.
long endDateMilli = (new Date()).getTime() - (7L*24L*60L*60L*1000L); // One week ago.
SimpleDateFormat dateFormatter = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'");
dateFormatter.setTimeZone(TimeZone.getTimeZone("UTC"));
String startDate = dateFormatter.format(startDateMilli);
String endDate = dateFormatter.format(endDateMilli);
Condition rangeKeyCondition = new Condition()
.withComparisonOperator(ComparisonOperator.BETWEEN.toString())
.withAttributeValueList(new AttributeValue().withS(startDate),
new AttributeValue().withS(endDate));
Reply replyKey = new Reply();
replyKey.setId(hashKey);
DynamoDBQueryExpression<Reply> queryExpression = new DynamoDBQueryExpression<Reply>()
.withHashKeyValues(replyKey)
.withRangeKeyCondition("ReplyDateTime", rangeKeyCondition);
List<Reply> betweenReplies = mapper.query(Reply.class, queryExpression);
for (Reply reply : betweenReplies) {
System.out.format("Id=%s, Message=%s, PostedBy=%s %n, PostedDateTime=%s %n",
reply.getId(), reply.getMessage(), reply.getPostedBy(), reply.getReplyDateTime() );
}
}
private static void FindBooksPricedLessThanSpecifiedValue(
DynamoDBMapper mapper,
String value) throws Exception {
System.out.println("FindBooksPricedLessThanSpecifiedValue: Scan ProductCatalog.");
DynamoDBScanExpression scanExpression = new DynamoDBScanExpression();
scanExpression.addFilterCondition("Price",
new Condition()
.withComparisonOperator(ComparisonOperator.LT)
.withAttributeValueList(new AttributeValue().withN(value)));
scanExpression.addFilterCondition("ProductCategory",
new Condition()
.withComparisonOperator(ComparisonOperator.EQ)
.withAttributeValueList(new AttributeValue().withS("Book")));
List<Book> scanResult = mapper.scan(Book.class, scanExpression);
for (Book book : scanResult) {
System.out.println(book);
}
}
private static void FindBicyclesOfSpecificTypeWithMultipleThreads(
DynamoDBMapper mapper,
int numberOfThreads,
String bicycleType) throws Exception {
System.out.println("FindBicyclesOfSpecificTypeWithMultipleThreads: Scan ProductCatalog With Multiple Threads.");
DynamoDBScanExpression scanExpression = new DynamoDBScanExpression();
scanExpression.addFilterCondition("ProductCategory",
new Condition()
.withComparisonOperator(ComparisonOperator.EQ)
.withAttributeValueList(new AttributeValue().withS("Bicycle")));
scanExpression.addFilterCondition("BicycleType",
new Condition()
.withComparisonOperator(ComparisonOperator.EQ)
.withAttributeValueList(new AttributeValue().withS(bicycleType)));
List<Bicycle> scanResult = mapper.parallelScan(Bicycle.class, scanExpression, numberOfThreads);
for (Bicycle bicycle : scanResult) {
System.out.println(bicycle);
}
}
@DynamoDBTable(tableName="ProductCatalog")
public static class Book {
private int id;
private String title;
private String ISBN;
private int price;
private int pageCount;
private String productCategory;
private boolean inPublication;
@DynamoDBHashKey(attributeName="Id")
public int getId() { return id; }
public void setId(int id) { this.id = id; }
@DynamoDBAttribute(attributeName="Title")
public String getTitle() { return title; }
public void setTitle(String title) { this.title = title; }
@DynamoDBAttribute(attributeName="ISBN")
public String getISBN() { return ISBN; }
public void setISBN(String ISBN) { this.ISBN = ISBN; }
@DynamoDBAttribute(attributeName="Price")
public int getPrice() { return price; }
public void setPrice(int price) { this.price = price; }
@DynamoDBAttribute(attributeName="PageCount")
public int getPageCount() { return pageCount; }
public void setPageCount(int pageCount) { this.pageCount = pageCount;}
@DynamoDBAttribute(attributeName="ProductCategory")
public String getProductCategory() { return productCategory; }
public void setProductCategory(String productCategory) { this.productCategory = productCategory; }
@DynamoDBAttribute(attributeName="InPublication")
public boolean getInPublication() { return inPublication; }
public void setInPublication(boolean inPublication) { this.inPublication = inPublication; }
@Override
public String toString() {
return "Book [ISBN=" + ISBN + ", price=" + price
+ ", product category=" + productCategory + ", id=" + id
+ ", title=" + title + "]";
}
}
@DynamoDBTable(tableName="ProductCatalog")
public static class Bicycle {
private int id;
private String title;
private String description;
private String bicycleType;
private String brand;
private int price;
private String gender;
private Set<String> color;
private String productCategory;
@DynamoDBHashKey(attributeName="Id")
public int getId() { return id; }
public void setId(int id) { this.id = id; }
@DynamoDBAttribute(attributeName="Title")
public String getTitle() { return title; }
public void setTitle(String title) { this.title = title; }
@DynamoDBAttribute(attributeName="Description")
public String getDescription() { return description; }
public void setDescription(String description) { this.description = description; }
@DynamoDBAttribute(attributeName="BicycleType")
public String getBicycleType() { return bicycleType; }
public void setBicycleType(String bicycleType) { this.bicycleType = bicycleType; }
@DynamoDBAttribute(attributeName="Brand")
public String getBrand() { return brand; }
public void setBrand(String brand) { this.brand = brand; }
@DynamoDBAttribute(attributeName="Price")
public int getPrice() { return price; }
public void setPrice(int price) { this.price = price; }
@DynamoDBAttribute(attributeName="Gender")
public String getGender() { return gender; }
public void setGender(String gender) { this.gender = gender; }
@DynamoDBAttribute(attributeName="Color")
public Set<String> getColor() { return color; }
public void setColor(Set<String> color) { this.color = color; }
@DynamoDBAttribute(attributeName="ProductCategory")
public String getProductCategory() { return productCategory; }
public void setProductCategory(String productCategory) { this.productCategory = productCategory; }
@Override
public String toString() {
return "Bicycle [Type=" + bicycleType + ", color=" + color + ", price=" + price
+ ", product category=" + productCategory + ", id=" + id
+ ", title=" + title + "]";
}
}
@DynamoDBTable(tableName="Reply")
public static class Reply {
private String id;
private String replyDateTime;
private String message;
private String postedBy;
@DynamoDBHashKey(attributeName="Id")
public String getId() { return id; }
public void setId(String id) { this.id = id; }
@DynamoDBRangeKey(attributeName="ReplyDateTime")
public String getReplyDateTime() { return replyDateTime; }
public void setReplyDateTime(String replyDateTime) { this.replyDateTime = replyDateTime; }
@DynamoDBAttribute(attributeName="Message")
public String getMessage() { return message; }
public void setMessage(String message) { this.message = message; }
@DynamoDBAttribute(attributeName="PostedBy")
public String getPostedBy() { return postedBy; }
public void setPostedBy(String postedBy) { this.postedBy = postedBy;}
}
@DynamoDBTable(tableName="Thread")
public static class Thread {
private String forumName;
private String subject;
private String message;
private String lastPostedDateTime;
private String lastPostedBy;
private Set<String> tags;
private int answered;
private int views;
private int replies;
@DynamoDBHashKey(attributeName="ForumName")
public String getForumName() { return forumName; }
public void setForumName(String forumName) { this.forumName = forumName; }
@DynamoDBRangeKey(attributeName="Subject")
public String getSubject() { return subject; }
public void setSubject(String subject) { this.subject = subject; }
@DynamoDBAttribute(attributeName="Message")
public String getMessage() { return message; }
public void setMessage(String message) { this.message = message; }
@DynamoDBAttribute(attributeName="LastPostedDateTime")
public String getLastPostedDateTime() { return lastPostedDateTime; }
public void setLastPostedDateTime(String lastPostedDateTime) { this.lastPostedDateTime = lastPostedDateTime; }
@DynamoDBAttribute(attributeName="LastPostedBy")
public String getLastPostedBy() { return lastPostedBy; }
public void setLastPostedBy(String lastPostedBy) { this.lastPostedBy = lastPostedBy;}
@DynamoDBAttribute(attributeName="Tags")
public Set<String> getTags() { return tags; }
public void setTags(Set<String> tags) { this.tags = tags; }
@DynamoDBAttribute(attributeName="Answered")
public int getAnswered() { return answered; }
public void setAnswered(int answered) { this.answered = answered; }
@DynamoDBAttribute(attributeName="Views")
public int getViews() { return views; }
public void setViews(int views) { this.views = views; }
@DynamoDBAttribute(attributeName="Replies")
public int getReplies() { return replies; }
public void setReplies(int replies) { this.replies = replies; }
}
@DynamoDBTable(tableName="Forum")
public static class Forum {
private String name;
private String category;
private int threads;
@DynamoDBHashKey(attributeName="Name")
public String getName() { return name; }
public void setName(String name) { this.name = name; }
@DynamoDBAttribute(attributeName="Category")
public String getCategory() { return category; }
public void setCategory(String category) { this.category = category; }
@DynamoDBAttribute(attributeName="Threads")
public int getThreads() { return threads; }
public void setThreads(int threads) { this.threads = threads;}
}
}
