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Telnyx Java API Library

Maven Central javadoc

The Telnyx Java SDK provides convenient access to the Telnyx REST API from applications written in Java.

It is generated with Stainless.

Javadocs are available on javadoc.io.

Installation ​

Gradle ​

implementation("com.telnyx.sdk:telnyx-java:5.0.0")

Maven ​

<dependency>
  <groupId>com.telnyx.sdk</groupId>
  <artifactId>telnyx-java</artifactId>
  <version>5.0.0</version>
</dependency>

Requirements ​

This library requires Java 8 or later.

Usage ​

import com.telnyx.sdk.client.TelnyxClient;
import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClient;
import com.telnyx.sdk.models.calls.CallDialParams;
import com.telnyx.sdk.models.calls.CallDialResponse;

// Configures using the `telnyx.apiKey` and `telnyx.baseUrl` system properties
// Or configures using the `TELNYX_API_KEY` and `TELNYX_BASE_URL` environment variables
TelnyxClient client = TelnyxOkHttpClient.fromEnv();

CallDialParams params = CallDialParams.builder()
    .connectionId("conn12345")
    .from("+15557654321")
    .to("+15551234567")
    .webhookUrl("https://your-webhook.url/events")
    .build();
CallDialResponse response = client.calls().dial(params);

Client configuration ​

Configure the client using system properties or environment variables:

import com.telnyx.sdk.client.TelnyxClient;
import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClient;

// Configures using the `telnyx.apiKey` and `telnyx.baseUrl` system properties
// Or configures using the `TELNYX_API_KEY` and `TELNYX_BASE_URL` environment variables
TelnyxClient client = TelnyxOkHttpClient.fromEnv();

Or manually:

import com.telnyx.sdk.client.TelnyxClient;
import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClient;

TelnyxClient client = TelnyxOkHttpClient.builder()
    .apiKey("My API Key")
    .build();

Or using a combination of the two approaches:

import com.telnyx.sdk.client.TelnyxClient;
import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClient;

TelnyxClient client = TelnyxOkHttpClient.builder()
    // Configures using the `telnyx.apiKey` and `telnyx.baseUrl` system properties
    // Or configures using the `TELNYX_API_KEY` and `TELNYX_BASE_URL` environment variables
    .fromEnv()
    .apiKey("My API Key")
    .build();

See this table for the available options:

SetterSystem propertyEnvironment variableRequiredDefault value
apiKeytelnyx.apiKeyTELNYX_API_KEYtrue-
baseUrltelnyx.baseUrlTELNYX_BASE_URLtrue"https://api.telnyx.com/v2"

System properties take precedence over environment variables.

[!TIP] Don't create more than one client in the same application. Each client has a connection pool and thread pools, which are more efficient to share between requests.

Modifying configuration ​

To temporarily use a modified client configuration, while reusing the same connection and thread pools, call withOptions() on any client or service:

import com.telnyx.sdk.client.TelnyxClient;

TelnyxClient clientWithOptions = client.withOptions(optionsBuilder -> {
    optionsBuilder.baseUrl("https://example.com");
    optionsBuilder.maxRetries(42);
});

The withOptions() method does not affect the original client or service.

Requests and responses ​

To send a request to the Telnyx API, build an instance of some Params class and pass it to the corresponding client method. When the response is received, it will be deserialized into an instance of a Java class.

For example, client.calls().dial(...) should be called with an instance of CallDialParams, and it will return an instance of CallDialResponse.

Immutability ​

Each class in the SDK has an associated builder or factory method for constructing it.

Each class is immutable once constructed. If the class has an associated builder, then it has a toBuilder() method, which can be used to convert it back to a builder for making a modified copy.

Because each class is immutable, builder modification will never affect already built class instances.

Asynchronous execution ​

The default client is synchronous. To switch to asynchronous execution, call the async() method:

import com.telnyx.sdk.client.TelnyxClient;
import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClient;
import com.telnyx.sdk.models.calls.CallDialParams;
import com.telnyx.sdk.models.calls.CallDialResponse;
import java.util.concurrent.CompletableFuture;

// Configures using the `telnyx.apiKey` and `telnyx.baseUrl` system properties
// Or configures using the `TELNYX_API_KEY` and `TELNYX_BASE_URL` environment variables
TelnyxClient client = TelnyxOkHttpClient.fromEnv();

CallDialParams params = CallDialParams.builder()
    .connectionId("conn12345")
    .from("+15557654321")
    .to("+15551234567")
    .webhookUrl("https://your-webhook.url/events")
    .build();
CompletableFuture<CallDialResponse> response = client.async().calls().dial(params);

Or create an asynchronous client from the beginning:

import com.telnyx.sdk.client.TelnyxClientAsync;
import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClientAsync;
import com.telnyx.sdk.models.calls.CallDialParams;
import com.telnyx.sdk.models.calls.CallDialResponse;
import java.util.concurrent.CompletableFuture;

// Configures using the `telnyx.apiKey` and `telnyx.baseUrl` system properties
// Or configures using the `TELNYX_API_KEY` and `TELNYX_BASE_URL` environment variables
TelnyxClientAsync client = TelnyxOkHttpClientAsync.fromEnv();

CallDialParams params = CallDialParams.builder()
    .connectionId("conn12345")
    .from("+15557654321")
    .to("+15551234567")
    .webhookUrl("https://your-webhook.url/events")
    .build();
CompletableFuture<CallDialResponse> response = client.calls().dial(params);

The asynchronous client supports the same options as the synchronous one, except most methods return CompletableFutures.

File uploads ​

The SDK defines methods that accept files.

To upload a file, pass a Path:

import com.telnyx.sdk.models.ai.audio.AudioTranscribeParams;
import com.telnyx.sdk.models.ai.audio.AudioTranscribeResponse;
import java.nio.file.Paths;

AudioTranscribeParams params = AudioTranscribeParams.builder()
    .model(AudioTranscribeParams.Model.DISTIL_WHISPER_DISTIL_LARGE_V2)
    .file(Paths.get("/path/to/file"))
    .build();
AudioTranscribeResponse response = client.ai().audio().transcribe(params);

Or an arbitrary InputStream:

import com.telnyx.sdk.models.ai.audio.AudioTranscribeParams;
import com.telnyx.sdk.models.ai.audio.AudioTranscribeResponse;
import java.net.URL;

AudioTranscribeParams params = AudioTranscribeParams.builder()
    .model(AudioTranscribeParams.Model.DISTIL_WHISPER_DISTIL_LARGE_V2)
    .file(new URL("https://example.com//path/to/file").openStream())
    .build();
AudioTranscribeResponse response = client.ai().audio().transcribe(params);

Or a byte[] array:

import com.telnyx.sdk.models.ai.audio.AudioTranscribeParams;
import com.telnyx.sdk.models.ai.audio.AudioTranscribeResponse;

AudioTranscribeParams params = AudioTranscribeParams.builder()
    .model(AudioTranscribeParams.Model.DISTIL_WHISPER_DISTIL_LARGE_V2)
    .file("content".getBytes())
    .build();
AudioTranscribeResponse response = client.ai().audio().transcribe(params);

Note that when passing a non-Path its filename is unknown so it will not be included in the request. To manually set a filename, pass a MultipartField:

import com.telnyx.sdk.core.MultipartField;
import com.telnyx.sdk.models.ai.audio.AudioTranscribeParams;
import com.telnyx.sdk.models.ai.audio.AudioTranscribeResponse;
import java.io.InputStream;
import java.net.URL;

AudioTranscribeParams params = AudioTranscribeParams.builder()
    .model(AudioTranscribeParams.Model.DISTIL_WHISPER_DISTIL_LARGE_V2)
    .file(MultipartField.<InputStream>builder()
        .value(new URL("https://example.com//path/to/file").openStream())
        .filename("/path/to/file")
        .build())
    .build();
AudioTranscribeResponse response = client.ai().audio().transcribe(params);

Binary responses ​

The SDK defines methods that return binary responses, which are used for API responses that shouldn't necessarily be parsed, like non-JSON data.

These methods return HttpResponse:

import com.telnyx.sdk.core.http.HttpResponse;
import com.telnyx.sdk.models.documents.DocumentDownloadParams;

HttpResponse response = client.documents().download("6a09cdc3-8948-47f0-aa62-74ac943d6c58");

To save the response content to a file, use the Files.copy(...) method:

import com.telnyx.sdk.core.http.HttpResponse;
import java.nio.file.Files;
import java.nio.file.Paths;
import java.nio.file.StandardCopyOption;

try (HttpResponse response = client.documents().download(params)) {
    Files.copy(
        response.body(),
        Paths.get(path),
        StandardCopyOption.REPLACE_EXISTING
    );
} catch (Exception e) {
    System.out.println("Something went wrong!");
    throw new RuntimeException(e);
}

Or transfer the response content to any OutputStream:

import com.telnyx.sdk.core.http.HttpResponse;
import java.nio.file.Files;
import java.nio.file.Paths;

try (HttpResponse response = client.documents().download(params)) {
    response.body().transferTo(Files.newOutputStream(Paths.get(path)));
} catch (Exception e) {
    System.out.println("Something went wrong!");
    throw new RuntimeException(e);
}

Raw responses ​

The SDK defines methods that deserialize responses into instances of Java classes. However, these methods don't provide access to the response headers, status code, or the raw response body.

To access this data, prefix any HTTP method call on a client or service with withRawResponse():

import com.telnyx.sdk.core.http.Headers;
import com.telnyx.sdk.core.http.HttpResponseFor;
import com.telnyx.sdk.models.numberorders.NumberOrderCreateParams;
import com.telnyx.sdk.models.numberorders.NumberOrderCreateResponse;

NumberOrderCreateParams params = NumberOrderCreateParams.builder()
    .addPhoneNumber(NumberOrderCreateParams.PhoneNumber.builder()
        .phoneNumber("+15558675309")
        .build())
    .build();
HttpResponseFor<NumberOrderCreateResponse> numberOrder = client.numberOrders().withRawResponse().create(params);

int statusCode = numberOrder.statusCode();
Headers headers = numberOrder.headers();

You can still deserialize the response into an instance of a Java class if needed:

import com.telnyx.sdk.models.numberorders.NumberOrderCreateResponse;

NumberOrderCreateResponse parsedNumberOrder = numberOrder.parse();

Error handling ​

The SDK throws custom unchecked exception types:

Logging ​

The SDK uses the standard OkHttp logging interceptor.

Enable logging by setting the TELNYX_LOG environment variable to info:

$ export TELNYX_LOG=info

Or to debug for more verbose logging:

$ export TELNYX_LOG=debug

ProGuard and R8 ​

Although the SDK uses reflection, it is still usable with ProGuard and R8 because telnyx-java-core is published with a configuration file containing keep rules.

ProGuard and R8 should automatically detect and use the published rules, but you can also manually copy the keep rules if necessary.

Jackson ​

The SDK depends on Jackson for JSON serialization/deserialization. It is compatible with version 2.13.4 or higher, but depends on version 2.18.2 by default.

The SDK throws an exception if it detects an incompatible Jackson version at runtime (e.g. if the default version was overridden in your Maven or Gradle config).

If the SDK threw an exception, but you're certain the version is compatible, then disable the version check using the checkJacksonVersionCompatibility on TelnyxOkHttpClient or TelnyxOkHttpClientAsync.

[!CAUTION] We make no guarantee that the SDK works correctly when the Jackson version check is disabled.

Network options ​

Retries ​

The SDK automatically retries 2 times by default, with a short exponential backoff between requests.

Only the following error types are retried:

  • Connection errors (for example, due to a network connectivity problem)
  • 408 Request Timeout
  • 409 Conflict
  • 429 Rate Limit
  • 5xx Internal

The API may also explicitly instruct the SDK to retry or not retry a request.

To set a custom number of retries, configure the client using the maxRetries method:

import com.telnyx.sdk.client.TelnyxClient;
import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClient;

TelnyxClient client = TelnyxOkHttpClient.builder()
    .fromEnv()
    .maxRetries(4)
    .build();

Timeouts ​

Requests time out after 1 minute by default.

To set a custom timeout, configure the method call using the timeout method:

import com.telnyx.sdk.models.calls.CallDialResponse;

CallDialResponse response = client.calls().dial(
  params, RequestOptions.builder().timeout(Duration.ofSeconds(30)).build()
);

Or configure the default for all method calls at the client level:

import com.telnyx.sdk.client.TelnyxClient;
import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClient;
import java.time.Duration;

TelnyxClient client = TelnyxOkHttpClient.builder()
    .fromEnv()
    .timeout(Duration.ofSeconds(30))
    .build();

Proxies ​

To route requests through a proxy, configure the client using the proxy method:

import com.telnyx.sdk.client.TelnyxClient;
import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClient;
import java.net.InetSocketAddress;
import java.net.Proxy;

TelnyxClient client = TelnyxOkHttpClient.builder()
    .fromEnv()
    .proxy(new Proxy(
      Proxy.Type.HTTP, new InetSocketAddress(
        "https://example.com", 8080
      )
    ))
    .build();

HTTPS ​

[!NOTE] Most applications should not call these methods, and instead use the system defaults. The defaults include special optimizations that can be lost if the implementations are modified.

To configure how HTTPS connections are secured, configure the client using the sslSocketFactory, trustManager, and hostnameVerifier methods:

import com.telnyx.sdk.client.TelnyxClient;
import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClient;

TelnyxClient client = TelnyxOkHttpClient.builder()
    .fromEnv()
    // If `sslSocketFactory` is set, then `trustManager` must be set, and vice versa.
    .sslSocketFactory(yourSSLSocketFactory)
    .trustManager(yourTrustManager)
    .hostnameVerifier(yourHostnameVerifier)
    .build();

Custom HTTP client ​

The SDK consists of three artifacts:

This structure allows replacing the SDK's default HTTP client without pulling in unnecessary dependencies.

Customized OkHttpClient ​

[!TIP] Try the available network options before replacing the default client.

To use a customized OkHttpClient:

  1. Replace your telnyx-java dependency with telnyx-java-core
  2. Copy telnyx-java-client-okhttp's OkHttpClient class into your code and customize it
  3. Construct TelnyxClientImpl or TelnyxClientAsyncImpl, similarly to TelnyxOkHttpClient or TelnyxOkHttpClientAsync, using your customized client

Completely custom HTTP client ​

To use a completely custom HTTP client:

  1. Replace your telnyx-java dependency with telnyx-java-core
  2. Write a class that implements the HttpClient interface
  3. Construct TelnyxClientImpl or TelnyxClientAsyncImpl, similarly to TelnyxOkHttpClient or TelnyxOkHttpClientAsync, using your new client class

Undocumented API functionality ​

The SDK is typed for convenient usage of the documented API. However, it also supports working with undocumented or not yet supported parts of the API.

Parameters ​

To set undocumented parameters, call the putAdditionalHeader, putAdditionalQueryParam, or putAdditionalBodyProperty methods on any Params class:

import com.telnyx.sdk.core.JsonValue;
import com.telnyx.sdk.models.calls.CallDialParams;

CallDialParams params = CallDialParams.builder()
    .putAdditionalHeader("Secret-Header", "42")
    .putAdditionalQueryParam("secret_query_param", "42")
    .putAdditionalBodyProperty("secretProperty", JsonValue.from("42"))
    .build();

These can be accessed on the built object later using the _additionalHeaders(), _additionalQueryParams(), and _additionalBodyProperties() methods.

To set undocumented parameters on nested headers, query params, or body classes, call the putAdditionalProperty method on the nested class:

import com.telnyx.sdk.core.JsonValue;
import com.telnyx.sdk.models.calls.CallDialParams;

CallDialParams params = CallDialParams.builder()
    .answeringMachineDetectionConfig(CallDialParams.AnsweringMachineDetectionConfig.builder()
        .putAdditionalProperty("secretProperty", JsonValue.from("42"))
        .build())
    .build();

These properties can be accessed on the nested built object later using the _additionalProperties() method.

To set a documented parameter or property to an undocumented or not yet supported value, pass a JsonValue object to its setter:

import com.telnyx.sdk.core.JsonValue;
import com.telnyx.sdk.models.calls.CallDialParams;

CallDialParams params = CallDialParams.builder()
    .connectionId(JsonValue.from(42))
    .from("+15557654321")
    .to("+15551234567")
    .webhookUrl("https://your-webhook.url/events")
    .build();

The most straightforward way to create a JsonValue is using its from(...) method:

import com.telnyx.sdk.core.JsonValue;
import java.util.List;
import java.util.Map;

// Create primitive JSON values
JsonValue nullValue = JsonValue.from(null);
JsonValue booleanValue = JsonValue.from(true);
JsonValue numberValue = JsonValue.from(42);
JsonValue stringValue = JsonValue.from("Hello World!");

// Create a JSON array value equivalent to `["Hello", "World"]`
JsonValue arrayValue = JsonValue.from(List.of(
  "Hello", "World"
));

// Create a JSON object value equivalent to `{ "a": 1, "b": 2 }`
JsonValue objectValue = JsonValue.from(Map.of(
  "a", 1,
  "b", 2
));

// Create an arbitrarily nested JSON equivalent to:
// {
//   "a": [1, 2],
//   "b": [3, 4]
// }
JsonValue complexValue = JsonValue.from(Map.of(
  "a", List.of(
    1, 2
  ),
  "b", List.of(
    3, 4
  )
));

Normally a Builder class's build method will throw IllegalStateException if any required parameter or property is unset.

To forcibly omit a required parameter or property, pass JsonMissing:

import com.telnyx.sdk.core.JsonMissing;
import com.telnyx.sdk.models.calls.CallDialParams;

CallDialParams params = CallDialParams.builder()
    .from("+18005550101")
    .to("+18005550100 or sip:username@sip.telnyx.com")
    .connectionId(JsonMissing.of())
    .build();

Response properties ​

To access undocumented response properties, call the _additionalProperties() method:

import com.telnyx.sdk.core.JsonValue;
import java.util.Map;

Map<String, JsonValue> additionalProperties = client.calls().dial(params)._additionalProperties();
JsonValue secretPropertyValue = additionalProperties.get("secretProperty");

String result = secretPropertyValue.accept(new JsonValue.Visitor<>() {
    @Override
    public String visitNull() {
        return "It's null!";
    }

    @Override
    public String visitBoolean(boolean value) {
        return "It's a boolean!";
    }

    @Override
    public String visitNumber(Number value) {
        return "It's a number!";
    }

    // Other methods include `visitMissing`, `visitString`, `visitArray`, and `visitObject`
    // The default implementation of each unimplemented method delegates to `visitDefault`, which throws by default, but can also be overridden
});

To access a property's raw JSON value, which may be undocumented, call its _ prefixed method:

import com.telnyx.sdk.core.JsonField;
import java.util.Optional;

JsonField<String> connectionId = client.calls().dial(params)._connectionId();

if (connectionId.isMissing()) {
  // The property is absent from the JSON response
} else if (connectionId.isNull()) {
  // The property was set to literal null
} else {
  // Check if value was provided as a string
  // Other methods include `asNumber()`, `asBoolean()`, etc.
  Optional<String> jsonString = connectionId.asString();

  // Try to deserialize into a custom type
  MyClass myObject = connectionId.asUnknown().orElseThrow().convert(MyClass.class);
}

Response validation ​

In rare cases, the API may return a response that doesn't match the expected type. For example, the SDK may expect a property to contain a String, but the API could return something else.

By default, the SDK will not throw an exception in this case. It will throw TelnyxInvalidDataException only if you directly access the property.

If you would prefer to check that the response is completely well-typed upfront, then either call validate():

import com.telnyx.sdk.models.calls.CallDialResponse;

CallDialResponse response = client.calls().dial(params).validate();

Or configure the method call to validate the response using the responseValidation method:

import com.telnyx.sdk.models.calls.CallDialResponse;

CallDialResponse response = client.calls().dial(
  params, RequestOptions.builder().responseValidation(true).build()
);

Or configure the default for all method calls at the client level:

import com.telnyx.sdk.client.TelnyxClient;
import com.telnyx.sdk.client.okhttp.TelnyxOkHttpClient;

TelnyxClient client = TelnyxOkHttpClient.builder()
    .fromEnv()
    .responseValidation(true)
    .build();

FAQ ​

Why don't you use plain enum classes? ​

Java enum classes are not trivially forwards compatible. Using them in the SDK could cause runtime exceptions if the API is updated to respond with a new enum value.

Why do you represent fields using JsonField<T> instead of just plain T? ​

Using JsonField<T> enables a few features:

Why don't you use data classes? ​

It is not backwards compatible to add new fields to a data class and we don't want to introduce a breaking change every time we add a field to a class.

Why don't you use checked exceptions? ​

Checked exceptions are widely considered a mistake in the Java programming language. In fact, they were omitted from Kotlin for this reason.

Checked exceptions:

  • Are verbose to handle
  • Encourage error handling at the wrong level of abstraction, where nothing can be done about the error
  • Are tedious to propagate due to the function coloring problem
  • Don't play well with lambdas (also due to the function coloring problem)

Semantic versioning ​

This package generally follows SemVer conventions, though certain backwards-incompatible changes may be released as minor versions:

  1. Changes to library internals which are technically public but not intended or documented for external use. (Please open a GitHub issue to let us know if you are relying on such internals.)
  2. Changes that we do not expect to impact the vast majority of users in practice.

We take backwards-compatibility seriously and work hard to ensure you can rely on a smooth upgrade experience.

We are keen for your feedback; please open an issue with questions, bugs, or suggestions.

Add Dependency ​

<dependency>
	<groupId>software.amazon.awssdk</groupId>
	<artifactId>s3</artifactId>
	<version>2.20.0</version> <!--  Or any 2.x version -->
</dependency>

Create S3 Bucket ​

import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
import software.amazon.awssdk.auth.credentials.StaticCredentialsProvider;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.s3.S3Client;
import software.amazon.awssdk.services.s3.model.CreateBucketRequest;

public class CreateBucket {

	public static void main(String[] args) {
    	String bucketName = "--your-bucket-name--";
    	Region region = Region.US_EAST_1;
    	String telnyxUrl = "https://us-central-1.telnyxcloudstorage.com";
    	String telnyxApiKey = "-- api key --";

    	// Create an S3 client
    	S3Client s3 = S3Client.builder()
            	.region(region)
            	.endpointOverride(URI.create(telnyxUrl))
                // Only perform CRC checks `when_required`
                .requestChecksumCalculation(RequestChecksumCalculation.WHEN_REQUIRED)
                .responseChecksumValidation(ResponseChecksumValidation.WHEN_REQUIRED)
            	.credentialsProvider(
                    	StaticCredentialsProvider.create(AwsBasicCredentials.create(telnyxApiKey, "does not matter")))
            	.build();

    	// create bucket
    	CreateBucketRequest createBucketRequest = CreateBucketRequest.builder()
            	.bucket(bucketName)
            	.build();

    	s3.createBucket(createBucketRequest);
    	System.out.println("Bucket created successfully: " + bucketName);

    	// Close the S3 client
    	s3.close();
	}

}

Upload an Object ​

import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
import software.amazon.awssdk.auth.credentials.StaticCredentialsProvider;
import software.amazon.awssdk.core.sync.RequestBody;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.s3.S3Client;
import software.amazon.awssdk.services.s3.model.PutObjectRequest;

import java.net.URI;
import java.nio.file.Paths;

public class UploadObjectToS3 {


	public static void main(String[] args) {
    	String bucketName = "--your-bucket-name--";
    	String keyName = "your-object-key";
    	String filePath = "--path to file for upload--";

    	Region region = Region.US_EAST_1;
    	String telnyxUrl = "https://us-central-1.telnyxcloudstorage.com";
    	String telnyxApiKey = "--your api key --";

    	// Create an S3 client
    	S3Client s3 = S3Client.builder()
            	.region(region)
            	.endpointOverride(URI.create(telnyxUrl))
            	.credentialsProvider(
                    	StaticCredentialsProvider.create(AwsBasicCredentials.create(telnyxApiKey, "does not matter")))
            	.build();

    	// upload object
    	PutObjectRequest putObjectRequest = PutObjectRequest.builder()
            	.bucket(bucketName)
            	.key(keyName)
            	.build();

    	// Upload the file to S3
    	s3.putObject(putObjectRequest, RequestBody.fromFile(Paths.get(filePath)));

    	// Close the S3 client
    	s3.close();
	}

}

List Objects ​

import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
import software.amazon.awssdk.auth.credentials.StaticCredentialsProvider;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.s3.S3Client;
import software.amazon.awssdk.services.s3.model.ListObjectsV2Request;
import software.amazon.awssdk.services.s3.model.ListObjectsV2Response;
import software.amazon.awssdk.services.s3.model.S3Object;

import java.net.URI;

public class ListObjects {

	public static void main(String[] args) {
    	String bucketName = "--your-bucket-name--";
    	Region region = Region.US_EAST_1;
    	String telnyxUrl = "https://us-central-1.telnyxcloudstorage.com";
    	String telnyxApiKey = "--your api key --";

    	// Create an S3 client
    	S3Client s3 = S3Client.builder()
            	.region(region)
            	.endpointOverride(URI.create(telnyxUrl))
            	.credentialsProvider(
                    	StaticCredentialsProvider.create(AwsBasicCredentials.create(telnyxApiKey, "does not matter")))
            	.build();
    	// Create a ListObjectsV2Request
    	ListObjectsV2Request listObjectsRequest = ListObjectsV2Request.builder()
            	.bucket(bucketName)
            	.build();

    	// Get the list of objects in the bucket
    	ListObjectsV2Response listObjectsResponse = s3.listObjectsV2(listObjectsRequest);

    	for (S3Object s3Object : listObjectsResponse.contents()) {
        	System.out.println( s3Object.key());
    	}

    	// Close the S3 client
    	s3.close();
	}

}

Download Object ​

import software.amazon.awssdk.auth.credentials.AwsBasicCredentials;
import software.amazon.awssdk.auth.credentials.StaticCredentialsProvider;
import software.amazon.awssdk.core.ResponseBytes;
import software.amazon.awssdk.core.sync.ResponseTransformer;
import software.amazon.awssdk.regions.Region;
import software.amazon.awssdk.services.s3.S3Client;
import software.amazon.awssdk.services.s3.model.GetObjectRequest;
import software.amazon.awssdk.services.s3.model.GetObjectResponse;

import java.io.File;
import java.io.FileOutputStream;
import java.io.IOException;
import java.net.URI;

public class DownloadObject {

	public static void main(String[] args) throws IOException {
    	String bucketName = "--your-bucket-name--";
    	Region region = Region.US_EAST_1;
    	String telnyxUrl = "https://us-central-1.telnyxcloudstorage.com";
    	String telnyxApiKey = "--your api key --";
    	String keyName = "your-object-key";

    	S3Client s3 = S3Client.builder()
            	.region(region)
            	.endpointOverride(URI.create(telnyxUrl))
            	.credentialsProvider(
                    	StaticCredentialsProvider.create(AwsBasicCredentials.create(telnyxApiKey, "does not matter")))
            	.build();

    	// Create a GetObjectRequest
    	GetObjectRequest getObjectRequest = GetObjectRequest.builder()
            	.bucket(bucketName)
            	.key(keyName)
            	.build();

    	// Download the object and transform the response to a byte array
    	ResponseBytes<GetObjectResponse> objectBytes = s3.getObject(getObjectRequest, ResponseTransformer.toBytes());

    	// Write the file to the specified path
    	File downloadedFile = new File("-- path to where to save the file --");
    	try (FileOutputStream fos = new FileOutputStream(downloadedFile)) {
        	fos.write(objectBytes.asByteArray());
        	System.out.println("File downloaded successfully to -- path to where to save the file --");
    	}

    	// Close the S3 client
    	s3.close();
	}

}

Generate Presigned URLs for Upload and Download ​

In order for this part to work, we will need to add json decoding library and http client. Any libraries will do, but for this example we picked: gson and okhttp3.

<dependency>
    	<groupId>com.squareup.okhttp3</groupId>
    	<artifactId>okhttp</artifactId>
    	<version>4.9.2</version>
</dependency>
<dependency>
    	<groupId>com.google.code.gson</groupId>
    	<artifactId>gson</artifactId>
    	<version>2.8.7</version>
</dependency>
import com.google.gson.Gson;
import com.google.gson.reflect.TypeToken;
import okhttp3.*;

import java.io.IOException;
import java.util.Map;

public class GeneratePresignedURLAndDownloadObject {

	public static void main(String[] args) throws IOException {
    	OkHttpClient httpClient = new OkHttpClient();
    	Gson gson = new Gson();

    	String presignedUrlRequestJson = gson.toJson(Map.of("TTL", 30));
    	RequestBody presignedUrlRequestBody = RequestBody.create(MediaType.parse("application/json"), presignedUrlRequestJson);

    	Request presignedUrlRequest = new Request.Builder()
            	.url("https://api.telnyx.com/v2/storage/buckets/-- name of the bucket --/--name of the object--/presigned_url")
            	.header("Authorization", "Bearer --your api key---")
            	.post(presignedUrlRequestBody)
            	.build();

    	try (Response response = httpClient.newCall(presignedUrlRequest).execute()) {
        	if (!response.isSuccessful()) {
            	throw new IOException("Failed to create presigned URL: " + response);
        	}
        	String responseBody = response.body().string();
        	Map<String, Object> responseBodyMap = gson.fromJson(responseBody, new TypeToken<Map<String, Object>>() {}.getType());
        	String presignedUrl = ((Map<String, String>) responseBodyMap.get("data")).get("presigned_url");

        	System.out.println("Presigned URL: " + presignedUrl);

        	// 6. Download the file using the presigned URL
        	Request downloadRequest = new Request.Builder()
                	.url(presignedUrl)
                	.build();

        	try (Response downloadResponse = httpClient.newCall(downloadRequest).execute()) {
            	if (!downloadResponse.isSuccessful()) {
                	throw new IOException("Failed to download file using presigned URL: " + downloadResponse);
            	}
            	System.out.println("Downloaded via presigned URL: " + downloadResponse.body().string());
        	}
    	}
	}
}