DynamoDB support for Java source code

public static void main(String[] args)
    {
        final String USAGE = "\n" +
            "Usage:\n" +
            "    CreateTable <table>\n\n" +
            "Where:\n" +
            "    table - the table to create.\n\n" +
            "Example:\n" +
            "    CreateTable HelloTable\n";

        if (args.length < 1) {
            System.out.println(USAGE);
            System.exit(1);
        }

        /* Read the name from command args */
        String table_name = "Customer Table";

        System.out.format(
            "Creating table \"%s\" with a simple primary key: \"Name\".\n",
            table_name);

        CreateTableRequest request = new CreateTableRequest()
            .withAttributeDefinitions(new AttributeDefinition(
                     "Name", ScalarAttributeType.S))
            .withKeySchema(new KeySchemaElement("Name", KeyType.HASH))
            .withProvisionedThroughput(new ProvisionedThroughput(
                     new Long(10), new Long(10)))
            .withTableName(table_name);

        final AmazonDynamoDB ddb = AmazonDynamoDBClientBuilder.defaultClient();

        try {
            CreateTableResult result = ddb.createTable(request);
            System.out.println(result.getTableDescription().getTableName());
        } catch (AmazonServiceException e) {
            System.err.println(e.getErrorMessage());
            System.exit(1);
        }
        System.out.println("Done!");
    }

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

        AmazonDynamoDB dynamoDBClient = AmazonDynamoDBClientBuilder
            .standard()
            .withRegion(Regions.US_EAST_2)
            .withCredentials(new DefaultAWSCredentialsProviderChain())
            .build();
		int maxItemCount = 100;
		for (Integer i = 1; i <= maxItemCount; i++) {
            System.out.println("Processing item " + i + " of " + maxItemCount);

            // Write a new item
            Map<String, AttributeValue> item = new HashMap<>();
            item.put("Id", new AttributeValue().withN(i.toString()));
            item.put("Message", new AttributeValue().withS("New item!"));
            dynamoDBClient.putItem(tableName, item);
	}
}

public static void main(String[] args)
    {
        final String USAGE = "\n" +
            "Usage:\n" +
            "    DeleteTable <table>\n\n" +
            "Where:\n" +
            "    table - the table to delete.\n\n" +
            "Example:\n" +
            "    DeleteTable Greetings\n\n" +
            "**Warning** This program will actually delete the table\n" +
            "            that you specify!\n";

        if (args.length < 1) {
            System.out.println(USAGE);
            System.exit(1);
        }

        String table_name = "CustomerTable";

        System.out.format("Deleting table %s...\n", table_name);

        final AmazonDynamoDB ddb = AmazonDynamoDBClientBuilder.defaultClient();

        try {
            ddb.deleteTable(table_name);
        } catch (AmazonServiceException e) {
            System.err.println(e.getErrorMessage());
            System.exit(1);
        }
        System.out.println("Done!");
    }

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

        AmazonDynamoDB dynamoDBClient = AmazonDynamoDBClientBuilder
            .standard()
            .withRegion(Regions.US_EAST_2)
            .withCredentials(new DefaultAWSCredentialsProviderChain())
            .build();
	
		 Map<String, AttributeValue> key = new HashMap<>();
            key.put("Id", new AttributeValue().withN(i.toString()));
            Map<String, AttributeValueUpdate> attributeUpdates = new HashMap<>();
            attributeUpdates.put("Message", new AttributeValueUpdate()
                .withAction(AttributeAction.PUT)
                .withValue(new AttributeValue()
                    .withS("This item has changed")));
            dynamoDBClient.updateItem(tableName, key, attributeUpdates);

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

        AmazonDynamoDB dynamoDBClient = AmazonDynamoDBClientBuilder
            .standard()
            .withRegion(Regions.US_EAST_2)
            .withCredentials(new DefaultAWSCredentialsProviderChain())
            .build();
		String tableName = "TestTableForStreams";
		// Print the stream settings for the table
		DescribeTableResult describeTableResult = dynamoDBClient.describeTable(tableName);
        String streamArn = describeTableResult.getTable().getLatestStreamArn();
        System.out.println("Current stream ARN for " + tableName + ": " +
            describeTableResult.getTable().getLatestStreamArn());

public void likeMysfit(String mysfitId) {

        Mysfit mysfitToUpdate = mapper.load(Mysfit.class, mysfitId);
        Integer likes = mysfitToUpdate.getLikes() + 1;
        mysfitToUpdate.setLikes(likes);
        mapper.save(mysfitToUpdate);

    }

public Mysfits queryMysfits(String filter, String value) {

        HashMap<String, AttributeValue> attribValue = new HashMap<String, AttributeValue>();
        attribValue.put(":"+value,  new AttributeValue().withS(value));

        DynamoDBQueryExpression<Mysfit> queryExpression = new DynamoDBQueryExpression<Mysfit>()
                .withIndexName(filter+"Index")
                .withKeyConditionExpression(filter + "= :" + value)
                .withExpressionAttributeValues(attribValue)
                .withConsistentRead(false);

        List<Mysfit> mysfits = mapper.query(Mysfit.class, queryExpression);
        Mysfits allMysfits = new Mysfits(mysfits);

        return allMysfits;
    }

public static void putItemInTable(DynamoDbClient ddb,
                                      String tableName,
                                      String key,
                                      String keyVal,
                                      String albumTitle,
                                      String albumTitleValue,
                                      String awards,
                                      String awardVal,
                                      String songTitle,
                                      String songTitleVal){

        HashMap<String,AttributeValue> itemValues = new HashMap<String,AttributeValue>();

        // Add all content to the table
        itemValues.put(key, AttributeValue.builder().s(keyVal).build());
        itemValues.put(songTitle, AttributeValue.builder().s(songTitleVal).build());
        itemValues.put(albumTitle, AttributeValue.builder().s(albumTitleValue).build());
        itemValues.put(awards, AttributeValue.builder().s(awardVal).build());

        PutItemRequest request = PutItemRequest.builder()
                .tableName(tableName)
                .item(itemValues)
                .build();

        try {
            ddb.putItem(request);
            System.out.println(tableName +" was successfully updated");

        } catch (ResourceNotFoundException e) {
            System.err.format("Error: The Amazon DynamoDB table \"%s\" can't be found.\n", tableName);
            System.err.println("Be sure that it exists and that you've typed its name correctly!");
            System.exit(1);
}

public static void deleteDynamoDBTable(DynamoDbClient ddb, String tableName) {

        DeleteTableRequest request = DeleteTableRequest.builder()
                .tableName(tableName)
                .build();

        try {
            ddb.deleteTable(request);

        } catch (DynamoDbException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
        System.out.println(tableName +" was successfully deleted!");
    }

public static void updateDynamoDBTable(DynamoDbClient ddb,
                                           String tableName,
                                           Long readCapacity,
                                           Long writeCapacity) {

        System.out.format(
                "Updating %s with new provisioned throughput values\n",
                tableName);
        System.out.format("Read capacity : %d\n", readCapacity);
        System.out.format("Write capacity : %d\n", writeCapacity);

        ProvisionedThroughput tableThroughput = ProvisionedThroughput.builder()
                .readCapacityUnits(readCapacity)
                .writeCapacityUnits(writeCapacity)
                .build();

        UpdateTableRequest request = UpdateTableRequest.builder()
                .provisionedThroughput(tableThroughput)
                .tableName(tableName)
                .build();

        try {
            ddb.updateTable(request);
        } catch (DynamoDbException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }

        System.out.println("Done!");
    }

public static int queryTable(DynamoDbClient ddb,
                                 String tableName,
                                 String partitionKeyName,
                                 String partitionKeyVal,
                                 String partitionAlias) {

        HashMap<String,String> attrNameAlias = new HashMap<String,String>();
        attrNameAlias.put(partitionAlias, partitionKeyName);

        // Set up mapping of the partition name with the value
        HashMap<String, AttributeValue> attrValues =
                new HashMap<String,AttributeValue>();

        attrValues.put(":"+partitionKeyName, AttributeValue.builder()
                .s(partitionKeyVal)
                .build());

        QueryRequest queryReq = QueryRequest.builder()
                .tableName(tableName)
                .keyConditionExpression(partitionAlias + " = :" + partitionKeyName)
                .expressionAttributeNames(attrNameAlias)
                .expressionAttributeValues(attrValues)
                .build();

        try {
            QueryResponse response = ddb.query(queryReq);
            return response.count();
        } catch (DynamoDbException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
       return -1;
    }

public static void putRecord(DynamoDbEnhancedClient enhancedClient) {

        try {
            DynamoDbTable<Customer> custTable = enhancedClient.table("Customer", TableSchema.fromBean(Customer.class));

            // Create an Instant
            LocalDate localDate = LocalDate.parse("2021-08-16");
            LocalDateTime localDateTime = localDate.atStartOfDay();
            Instant instant = localDateTime.toInstant(ZoneOffset.UTC);

            // Populate the Table
            Customer custRecord = new Customer();
            custRecord.setCustName("Susan red");
            custRecord.setId("id66");
            custRecord.setEmail("abc@xyz.com");
            custRecord.setRegistrationDate(instant) ;

            // Put the customer data into a DynamoDB table
            custTable.putItem(custRecord);

        } catch (DynamoDbException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
        System.out.println("done");
    }

public static String modifyItem(DynamoDbEnhancedClient enhancedClient, String keyVal, String email) {
        try {
            //Create a DynamoDbTable object
            DynamoDbTable<Customer> mappedTable = enhancedClient.table("Customer", TableSchema.fromBean(Customer.class));

            //Create a KEY object
            Key key = Key.builder()
                    .partitionValue(keyVal)
                    .build();

            // Get the item by using the key and update the email value.
            Customer customerRec = mappedTable.getItem(r->r.key(key));
            customerRec.setEmail(email);
            mappedTable.updateItem(customerRec);
            return customerRec.getEmail();

        } catch (DynamoDbException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }
        return "";
    }

public static String getItem(DynamoDbEnhancedClient enhancedClient) {
        try {
            //Create a DynamoDbTable object
            DynamoDbTable<Customer> mappedTable = enhancedClient.table("Customer", TableSchema.fromBean(Customer.class));

            //Create a KEY object
            Key key = Key.builder()
                    .partitionValue("id120")
                    .build();

            // Get the item by using the key
            Customer result = mappedTable.getItem(r->r.key(key));
            return "The email valie is "+result.getEmail();

        } catch (DynamoDbException e) {
            System.err.println(e.getMessage());
            System.exit(1);
        }

}