Ejemplo: creación, actualización, eliminación y enumeración de tablas mediante la API de documentos de AWS SDK for Java

En el siguiente ejemplo de código se utiliza la API de documentos del AWS SDK for Java para crear, actualizar y eliminar una tabla de Amazon DynamoDB (ExampleTable). Durante la actualización de la tabla, se aumentan los valores de desempeño provisionado. Además, en el ejemplo se enumeran todas las tablas de la cuenta y se obtiene la descripción de una de ellas en particular. Para step-by-step obtener instrucciones sobre cómo ejecutar el siguiente ejemplo, consulteEjemplos de código Java.

package com.amazonaws.codesamples.document;

import java.util.ArrayList;
import java.util.Iterator;

import com.amazonaws.services.dynamodbv2.AmazonDynamoDB;
import com.amazonaws.services.dynamodbv2.AmazonDynamoDBClientBuilder;
import com.amazonaws.services.dynamodbv2.document.DynamoDB;
import com.amazonaws.services.dynamodbv2.document.Table;
import com.amazonaws.services.dynamodbv2.document.TableCollection;
import com.amazonaws.services.dynamodbv2.model.AttributeDefinition;
import com.amazonaws.services.dynamodbv2.model.CreateTableRequest;
import com.amazonaws.services.dynamodbv2.model.KeySchemaElement;
import com.amazonaws.services.dynamodbv2.model.KeyType;
import com.amazonaws.services.dynamodbv2.model.ListTablesResult;
import com.amazonaws.services.dynamodbv2.model.ProvisionedThroughput;
import com.amazonaws.services.dynamodbv2.model.TableDescription;

public class DocumentAPITableExample {

    static AmazonDynamoDB client = AmazonDynamoDBClientBuilder.standard().build();
    static DynamoDB dynamoDB = new DynamoDB(client);

    static String tableName = "ExampleTable";

    public static void main(String[] args) throws Exception {

        createExampleTable();
        listMyTables();
        getTableInformation();
        updateExampleTable();

        deleteExampleTable();
    }

    static void createExampleTable() {

        try {

            List<AttributeDefinition> attributeDefinitions = new ArrayList<AttributeDefinition>();
            attributeDefinitions.add(new AttributeDefinition().withAttributeName("Id").withAttributeType("N"));

            List<KeySchemaElement> keySchema = new ArrayList<KeySchemaElement>();
            keySchema.add(new KeySchemaElement().withAttributeName("Id").withKeyType(KeyType.HASH)); // Partition
                                                                                                     // key

            CreateTableRequest request = new CreateTableRequest().withTableName(tableName).withKeySchema(keySchema)
                    .withAttributeDefinitions(attributeDefinitions).withProvisionedThroughput(
                            new ProvisionedThroughput().withReadCapacityUnits(5L).withWriteCapacityUnits(6L));

            System.out.println("Issuing CreateTable request for " + tableName);
            Table table = dynamoDB.createTable(request);

            System.out.println("Waiting for " + tableName + " to be created...this may take a while...");
            table.waitForActive();

            getTableInformation();

        } catch (Exception e) {
            System.err.println("CreateTable request failed for " + tableName);
            System.err.println(e.getMessage());
        }

    }

    static void listMyTables() {

        TableCollection<ListTablesResult> tables = dynamoDB.listTables();
        Iterator<Table> iterator = tables.iterator();

        System.out.println("Listing table names");

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

    static void getTableInformation() {

        System.out.println("Describing " + tableName);

        TableDescription tableDescription = dynamoDB.getTable(tableName).describe();
        System.out.format(
                "Name: %s:\n" + "Status: %s \n" + "Provisioned Throughput (read capacity units/sec): %d \n"
                        + "Provisioned Throughput (write capacity units/sec): %d \n",
                tableDescription.getTableName(), tableDescription.getTableStatus(),
                tableDescription.getProvisionedThroughput().getReadCapacityUnits(),
                tableDescription.getProvisionedThroughput().getWriteCapacityUnits());
    }

    static void updateExampleTable() {

        Table table = dynamoDB.getTable(tableName);
        System.out.println("Modifying provisioned throughput for " + tableName);

        try {
            table.updateTable(new ProvisionedThroughput().withReadCapacityUnits(6L).withWriteCapacityUnits(7L));

            table.waitForActive();
        } catch (Exception e) {
            System.err.println("UpdateTable request failed for " + tableName);
            System.err.println(e.getMessage());
        }
    }

    static void deleteExampleTable() {

        Table table = dynamoDB.getTable(tableName);
        try {
            System.out.println("Issuing DeleteTable request for " + tableName);
            table.delete();

            System.out.println("Waiting for " + tableName + " to be deleted...this may take a while...");

            table.waitForDelete();
        } catch (Exception e) {
            System.err.println("DeleteTable request failed for " + tableName);
            System.err.println(e.getMessage());
        }
    }

}