DynamoDB Java tutorial http://docs.aws.amazon.com/amazondynamodb/latest/gettingstartedguide/GettingStarted.Java.html

Dynamo.java

package com.chocksaway.util;

import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClient;
import com.amazonaws.services.dynamodbv2.document.*;
import com.amazonaws.services.dynamodbv2.document.spec.QuerySpec;
import com.amazonaws.services.dynamodbv2.document.spec.ScanSpec;
import com.amazonaws.services.dynamodbv2.document.utils.NameMap;
import com.amazonaws.services.dynamodbv2.document.utils.ValueMap;
import com.amazonaws.services.dynamodbv2.model.*;
import com.fasterxml.jackson.core.JsonFactory;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;
import com.fasterxml.jackson.databind.node.ObjectNode;

import java.io.File;
import java.io.IOException;
import java.util.Arrays;
import java.util.HashMap;
import java.util.Iterator;

/**
 * Author milesd on 30/07/2016.
 *
 * Dynamo DB tutorial http://docs.aws.amazon.com/amazondynamodb/latest/gettingstartedguide/GettingStarted.Java.html
 */
public class Dynamo {
    /**
     * Create Movies table
     *
     * @param client
     */
    private void createTable(DynamoDB client) {
        try {
            final String tableName = "Movies";
            System.out.println("Attempting to create table; please wait...");
            Table table = client.createTable(tableName,
                    Arrays.asList(
                            new KeySchemaElement("year", KeyType.HASH),  //Partition key
                            new KeySchemaElement("title", KeyType.RANGE)), //Sort key
                    Arrays.asList(
                            new AttributeDefinition("year", ScalarAttributeType.N),
                            new AttributeDefinition("title", ScalarAttributeType.S)),
                    new ProvisionedThroughput(10L, 10L));
            table.waitForActive();
            System.out.println("Success.  Table status: " + table.getDescription().getTableStatus());

        } catch (Exception e) {
            System.err.println("Unable to create table: ");
            System.err.println(e.getMessage());
        }
    }

    /**
     * List dynamodb tables
     *
     * @param client
     */
    private void listTables(DynamoDB client) {
        TableCollection<ListTablesResult> tables = client.listTables();
        Iterator<Table> iterator = tables.iterator();

        while (iterator.hasNext()) {
            Table table = iterator.next();
            System.out.println(table.getTableName());
        }
    }

    /**
     * Load moviedata.json
     *
     * @param dynamoDB
     */
    private void loadData(DynamoDB dynamoDB) {
        Table table = dynamoDB.getTable("Movies");

        JsonParser parser = null;
        JsonNode rootNode = null;
        try {
            parser = new JsonFactory()
                    .createParser(new File("moviedata.json"));
            rootNode = new ObjectMapper().readTree(parser);
        } catch (IOException e) {
            e.printStackTrace();
        }

        Iterator<JsonNode> iter = rootNode.iterator();

        ObjectNode currentNode;

        while (iter.hasNext()) {
            currentNode = (ObjectNode) iter.next();

            int year = currentNode.path("year").asInt();
            String title = currentNode.path("title").asText();

            try {
                table.putItem(new Item()
                        .withPrimaryKey("year", year, "title", title)
                        .withJSON("info", currentNode.path("info").toString()));
                System.out.println("PutItem succeeded: " + year + " " + title);

            } catch (Exception e) {
                System.err.println("Unable to add movie: " + year + " " + title);
                System.err.println(e.getMessage());
                break;
            }
        }
        try {
            parser.close();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

    /**
     * Query Movies table
     *
     * @param dynamoDB
     */
    private void queryTable(DynamoDB dynamoDB) {
        Table table = dynamoDB.getTable("Movies");
        HashMap<String, String> nameMap = new HashMap<String, String>();
        nameMap.put("#yr", "year");

        HashMap<String, Object> valueMap = new HashMap<String, Object>();
        valueMap.put(":yyyy", 1985);

        QuerySpec querySpec = new QuerySpec()
                .withKeyConditionExpression("#yr = :yyyy")
                .withNameMap(nameMap)
                .withValueMap(valueMap);

        ItemCollection<QueryOutcome> items = null;
        Iterator<Item> iterator = null;
        Item item = null;

        try {
            System.out.println("Movies from 1985");
            items = table.query(querySpec);

            iterator = items.iterator();
            while (iterator.hasNext()) {
                item = iterator.next();
                System.out.println(item.getNumber("year") + ": "
                        + item.getString("title"));
            }
        } catch (Exception e) {
            System.err.println("Unable to query movies from 1985");
            System.err.println(e.getMessage());
        }
    }

    /**
     * Scan Movies table
     *
     * @param dynamoDB
     */
    private void scanTable(DynamoDB dynamoDB) {
        Table table = dynamoDB.getTable("Movies");

        ScanSpec scanSpec = new ScanSpec()
                .withProjectionExpression("#yr, title, info.rating")
                .withFilterExpression("#yr between :start_yr and :end_yr")
                .withNameMap(new NameMap().with("#yr",  "year"))
                .withValueMap(new ValueMap().withNumber(":start_yr", 1983).withNumber(":end_yr", 1983));

        try {
            ItemCollection<ScanOutcome> items = table.scan(scanSpec);

            Iterator<Item> iter = items.iterator();
            while (iter.hasNext()) {
                Item item = iter.next();
                System.out.println(item.toString());
            }
        } catch (Exception e) {
            System.err.println("Unable to scan the table:");
            System.err.println(e.getMessage());
        }
    }

    /**
     * Get dynamodb client
     *
     * @return
     */
    private DynamoDB getDynamoDBClient() {
        AmazonDynamoDBClient client = new AmazonDynamoDBClient()
                .withEndpoint("http://localhost:8000");
        /**
         * set the region to local
         *
         * avoid getting default regions on localhost:
         *      aws_key_us-east-1.db
         *
         * you will see:
         *      aws_key_local.db
         */

        client.setSignerRegionOverride("local");
        return new DynamoDB(client);
    }

    public static void main(String[] args) {
        Dynamo myDynamo = new Dynamo();
        DynamoDB dynamoClient = myDynamo.getDynamoDBClient();

        myDynamo.createTable(dynamoClient);
        myDynamo.listTables(dynamoClient);
        myDynamo.loadData(dynamoClient);
        myDynamo.queryTable(dynamoClient);
        myDynamo.scanTable(dynamoClient);
    }
}