/telnyx-voice-advanced-java

name: telnyx-voice-advanced-java
description: >-
  Advanced call control features including DTMF sending, SIPREC recording, noise
  suppression, client state, and supervisor controls. This skill provides Java
  SDK examples.
metadata:
  author: telnyx
  product: voice-advanced
  language: java
  generated_by: telnyx-openapi-pipeline

<!-- Auto-generated from Telnyx OpenAPI specs. Do not edit. -->

Telnyx Voice Advanced - Java

Installation

<!-- Maven -->
<dependency>
    <groupId>com.telnyx.sdk</groupId>
    <artifactId>telnyx</artifactId>
    <version>6.95.0</version>
</dependency>

// Gradle
implementation("com.telnyx.sdk:telnyx:6.95.0")

Setup

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

// fromEnv() reads TELNYX_API_KEY and TELNYX_PUBLIC_KEY (the public key is required for
// client.webhooks().unwrap() — webhook verification)
TelnyxClient client = TelnyxOkHttpClient.fromEnv();

All examples below assume `client` is already initialized as shown above.

Error Handling

All API calls can fail with network errors, rate limits (429), validation errors (422), or authentication errors (401). Always handle errors in production code:

import com.telnyx.sdk.errors.TelnyxServiceException;

try {
    var result = client.messages().send(params);
} catch (TelnyxServiceException e) {
    System.err.println("API error " + e.statusCode() + ": " + e.getMessage());
    if (e.statusCode() == 422) {
        System.err.println("Validation error — check required fields and formats");
    } else if (e.statusCode() == 429) {
        // Rate limited — wait, then retry the request (bounded exponential backoff)
        Thread.sleep(1000);
        // ...retry the call here (give up after a few attempts)
    }
    throw e; // Re-throw: a failed request must never look like success to the caller
}

Common error codes: `401` invalid API key, `403` insufficient permissions, `404` resource not found, `422` validation error (check field formats), `429` rate limited (retry with exponential backoff).

Join AI Assistant Conversation

Add a participant to an existing AI assistant conversation. Use this command to bring an additional call leg into a running AI conversation.

`POST /calls/{call_control_id}/actions/ai_assistant_join` — Required: `conversation_id`, `participant`

Optional: `client_state` (string), `command_id` (string)

import com.telnyx.sdk.models.calls.actions.ActionJoinAiAssistantParams;
import com.telnyx.sdk.models.calls.actions.ActionJoinAiAssistantResponse;

ActionJoinAiAssistantParams params = ActionJoinAiAssistantParams.builder()
    .callControlId("v3:550e8400-e29b-41d4-a716-446655440000_gRU1OGRkYQ")
    .conversationId("v3:abc123")
    .participant(ActionJoinAiAssistantParams.Participant.builder()
        .id("v3:abc123def456")
        .role(ActionJoinAiAssistantParams.Participant.Role.USER)
        .build())
    .build();
ActionJoinAiAssistantResponse response = client.calls().actions().joinAiAssistant(params);

Returns: `conversation_id` (uuid), `result` (string)

Update client state

Updates the client state associated with the call. Client state is an opaque value echoed back in subsequent webhooks for the call, letting you correlate events with your application's state.

`PUT /calls/{call_control_id}/actions/client_state_update` — Required: `client_state`

import com.telnyx.sdk.models.calls.actions.ActionUpdateClientStateParams;
import com.telnyx.sdk.models.calls.actions.ActionUpdateClientStateResponse;

ActionUpdateClientStateParams params = ActionUpdateClientStateParams.builder()
    .callControlId("v3:550e8400-e29b-41d4-a716-446655440000_gRU1OGRkYQ")
    .clientState("aGF2ZSBhIG5pY2UgZGF5ID1d")
    .build();
ActionUpdateClientStateResponse response = client.calls().actions().updateClientState(params);

Returns: `result` (string)

Start Conversation Relay

Start a Conversation Relay session on an active call. Conversation Relay connects the call audio to your WebSocket so your application can exchange realtime messages with the caller while Telnyx handles speech recognition and text-to-speech. Only one AI Assistant or Conversation Relay session can be active on a call at a time.

`POST /calls/{call_control_id}/actions/conversation_relay_start`

Optional: `assistant` (object), `client_state` (string), `command_id` (string), `conversation_relay_dtmf_detection` (boolean), `conversation_relay_settings` (object), `conversation_relay_url` (string), `custom_parameters` (object), `dtmf_detection` (boolean), `greeting` (string), `interruptible` (enum: none, any, speech, dtmf), `interruptible_greeting` (enum: none, any, speech, dtmf), `interruption_settings` (object), `language` (string), `languages` (array[object]), `provider` (string), `structured_provider` (object), `transcription` (object), `transcription_engine` (enum: Google, Telnyx, Deepgram, Azure, xAI, AssemblyAI, Speechmatics, Soniox, A, B), `transcription_engine_config` (object), `tts_provider` (string), `url` (string), `voice` (string), `voice_settings` (object)

import com.telnyx.sdk.models.calls.actions.ActionStartConversationRelayParams;
import com.telnyx.sdk.models.calls.actions.ActionStartConversationRelayResponse;

ActionStartConversationRelayResponse response = client.calls().actions().startConversationRelay("v3:550e8400-e29b-41d4-a716-446655440000_gRU1OGRkYQ");

Returns: `conversation_relay_id` (string), `result` (string)

Stop Conversation Relay

Stop the active Conversation Relay session on a call.

`POST /calls/{call_control_id}/actions/conversation_relay_stop`

Optional: `client_state` (string), `command_id` (string)

import com.telnyx.sdk.models.calls.actions.ActionStopConversationRelayParams;
import com.telnyx.sdk.models.calls.actions.ActionStopConversationRelayResponse;

ActionStopConversationRelayResponse response = client.calls().actions().stopConversationRel