Telnyx Voice Java

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

Telnyx Voice - Java

Installation

<!-- Maven -->
<dependency>
    <groupId>com.telnyx.sdk</groupId>
    <artifactId>telnyx</artifactId>
    <version>6.82.0</version>
</dependency>

// Gradle
implementation("com.telnyx.sdk:telnyx:6.82.0")

Setup

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

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.models.calls.CallDialParams;
import com.telnyx.sdk.models.calls.CallDialResponse;
CallDialParams params = CallDialParams.builder()
    .connectionId("7267xxxxxxxxxxxxxx")
    .from("+18005550101")
    .to("+18005550100;secure=srtp")
    .build();
CallDialResponse response = client.calls().dial(params);

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).

Important Notes

• Phone numbers must be in E.164 format (e.g., +13125550001). Include the + prefix and country code. No spaces, dashes, or parentheses.
• Pagination: List methods return a page. Use .autoPager() for automatic iteration: for (var item : page.autoPager()) { ... }. For manual control, use .hasNextPage() and .nextPage().

Operational Caveats

• Call Control is event-driven. After dial() or an inbound webhook, issue follow-up commands from webhook handlers using the call_control_id in the event payload.
• Outbound and inbound flows are different: outbound calls start with dial(), while inbound calls must be answered from the incoming webhook before other commands run.
• A publicly reachable webhook endpoint is required for real call control. Without it, calls may connect but your application cannot drive the live call state.

Reference Use Rules

Do not invent Telnyx parameters, enums, response fields, or webhook fields.

• If the parameter, enum, or response field you need is not shown inline in this skill, read references/api-details.md before writing code.
• Before using any operation in ## Additional Operations, read the optional-parameters section and the response-schemas section.
• Before reading or matching webhook fields beyond the inline examples, read the webhook payload reference.

Core Tasks

Dial an outbound call

Primary voice entrypoint. Agents need the async call-control identifiers returned here.

client.calls().dial() — POST /calls

| Parameter | Type | Required | Description |

|-----------|------|----------|-------------|

| to | string (E.164) | Yes | The DID or SIP URI to dial out to. |

| from | string (E.164) | Yes | The from number to be used as the caller id presented to t... |

| connectionId | string (UUID) | Yes | The ID of the Call Control App (formerly ID of the connectio... |

| timeoutSecs | integer | No | The number of seconds that Telnyx will wait for the call to ... |

| billingGroupId | string (UUID) | No | Use this field to set the Billing Group ID for the call. |

| clientState | string | No | Use this field to add state to every subsequent webhook. |

| ... | | | +56 optional params in references/api-details.md |

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

CallDialParams params = CallDialParams.builder()
    .connectionId("7267xxxxxxxxxxxxxx")
    .from("+18005550101")
    .to("+18005550100;secure=srtp")
    .build();
CallDialResponse response = client.calls().dial(params);

Primary response fields:

• response.data.callControlId
• response.data.callLegId
• response.data.callSessionId
• response.data.isAlive
• response.data.recordingId
• response.data.callDuration

Answer an inbound call

Primary inbound call-control command.

client.calls().actions().answer() — POST /calls/{call_control_id}/actions/answer

| Parameter | Type | Required | Description |

|-----------|------|----------|-------------|

| callControlId | string (UUID) | Yes | Unique identifier and token for controlling the call |

| billingGroupId | string (UUID) | No | Use this field to set the Billing Group ID for the call. |

| clientState | string | No | Use this field to add state to every subsequent webhook. |

| webhookUrl | string (URL) | No | Use this field to override the URL for which Telnyx will sen... |

| ... | | | +29 optional params in references/api-details.md |

import com.telnyx.sdk.models.calls.actions.ActionAnswerParams;
import com.telnyx.sdk.models.calls.actions.ActionAnswerResponse;

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

Primary response fields:

• response.data.result
• response.data.recordingId

Transfer a live call

Common post-answer control path with downstream webhook implications.

client.calls().actions().transfer() — POST /calls/{call_control_id}/actions/transfer

| Parameter | Type | Required | Description |

|-----------|------|----------|-------------|

| to | string (E.164) | Yes | The DID or SIP URI to dial out to. |

| callControlId | string (UUID) | Yes | Unique identifier and token for controlling the call |

| timeoutSecs | integer | No | The number of seconds that Telnyx will wait for the call to ... |

| clientState | string | No | Use this field to add state to every subsequent webhook. |

| webhookUrl | string (URL) | No | Use this field to override the URL for which Telnyx will sen... |

| ... | | | +35 optional params in references/api-details.md |

import com.telnyx.sdk.models.calls.actions.ActionTransferParams;
import com.telnyx.sdk.models.calls.actions.ActionTransferResponse;

ActionTransferParams params = ActionTransferParams.builder()
    .callControlId("v3:550e8400-e29b-41d4-a716-446655440000_gRU1OGRkYQ")
    .to("+18005550100;secure=srtp")
    .build();
ActionTransferResponse response = client.calls().actions().transfer(params);

Primary response fields:

• response.data.result

Webhook Verification

Telnyx signs webhooks with Ed25519. Each request includes telnyx-signature-ed25519

and telnyx-timestamp headers. Always verify signatures in production:

import com.telnyx.sdk.core.UnwrapWebhookParams;
import com.telnyx.sdk.core.http.Headers;

// In your webhook handler (e.g., Spring — use raw body):
@PostMapping("/webhooks")
public ResponseEntity<String> handleWebhook(
    @RequestBody String payload,
    HttpServletRequest request) {
  try {
    Headers headers = Headers.builder()
        .put("telnyx-signature-ed25519", request.getHeader("telnyx-signature-ed25519"))
        .put("telnyx-timestamp", request.getHeader("telnyx-timestamp"))
        .build();
    var event = client.webhooks().unwrap(
        UnwrapWebhookParams.builder()
            .body(payload)
            .headers(headers)
            .build());
    // Signature valid — process the event
    System.out.println("Received webhook event");
    return ResponseEntity.ok("OK");
  } catch (Exception e) {
    System.err.println("Webhook verification failed: " + e.getMessage());
    return ResponseEntity.badRequest().body("Invalid signature");
  }
}

Webhooks

These webhook payload fields are inline because they are part of the primary integration path.

Call Answered

| Field | Type | Description |

|-------|------|-------------|

| data.record_type | enum: event | Identifies the type of the resource. |

| data.event_type | enum: call.answered | The type of event being delivered. |

| data.id | uuid | Identifies the type of resource. |

| data.occurred_at | date-time | ISO 8601 datetime of when the event occurred. |

| data.payload.call_control_id | string | Call ID used to issue commands via Call Control API. |

| data.payload.connection_id | string | Call Control App ID (formerly Telnyx connection ID) used in the call. |

| data.payload.call_leg_id | string | ID that is unique to the call and can be used to correlate webhook events. |

| data.payload.call_session_id | string | ID that is unique to the call session and can be used to correlate webhook ev... |

Call Hangup

| Field | Type | Description |

|-------|------|-------------|

| data.record_type | enum: event | Identifies the type of the resource. |

| data.event_type | enum: call.hangup | The type of event being delivered. |

| data.id | uuid | Identifies the type of resource. |

| data.occurred_at | date-time | ISO 8601 datetime of when the event occurred. |

| data.payload.call_control_id | string | Call ID used to issue commands via Call Control API. |

| data.payload.connection_id | string | Call Control App ID (formerly Telnyx connection ID) used in the call. |

| data.payload.call_leg_id | string | ID that is unique to the call and can be used to correlate webhook events. |

| data.payload.call_session_id | string | ID that is unique to the call session and can be used to correlate webhook ev... |

Call Initiated

| Field | Type | Description |

|-------|------|-------------|

| data.record_type | enum: event | Identifies the type of the resource. |

| data.event_type | enum: call.initiated | The type of event being delivered. |

| data.id | uuid | Identifies the type of resource. |

| data.occurred_at | date-time | ISO 8601 datetime of when the event occurred. |

| data.payload.call_control_id | string | Call ID used to issue commands via Call Control API. |

| data.payload.connection_id | string | Call Control App ID (formerly Telnyx connection ID) used in the call. |

| data.payload.connection_codecs | string | The list of comma-separated codecs enabled for the connection. |

| data.payload.offered_codecs | string | The list of comma-separated codecs offered by caller. |

If you need webhook fields that are not listed inline here, read the webhook payload reference before writing the handler.

Important Supporting Operations

Use these when the core tasks above are close to your flow, but you need a common variation or follow-up step.

Hangup call

End a live call from your webhook-driven control flow.

client.calls().actions().hangup() — POST /calls/{call_control_id}/actions/hangup

| Parameter | Type | Required | Description |

|-----------|------|----------|-------------|

| callControlId | string (UUID) | Yes | Unique identifier and token for controlling the call |

| clientState | string | No | Use this field to add state to every subsequent webhook. |

| commandId | string (UUID) | No | Use this field to avoid duplicate commands. |

| customHeaders | array[object] | No | Custom headers to be added to the SIP BYE message. |

import com.telnyx.sdk.models.calls.actions.ActionHangupParams;
import com.telnyx.sdk.models.calls.actions.ActionHangupResponse;

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

Primary response fields:

• response.data.result

Bridge calls

Trigger a follow-up action in an existing workflow rather than creating a new top-level resource.

client.calls().actions().bridge() — POST /calls/{call_control_id}/actions/bridge

| Parameter | Type | Required | Description |

|-----------|------|----------|-------------|

| callControlId | string (UUID) | Yes | The Call Control ID of the call you want to bridge with, can... |

| callControlId | string (UUID) | Yes | Unique identifier and token for controlling the call |

| clientState | string | No | Use this field to add state to every subsequent webhook. |

| commandId | string (UUID) | No | Use this field to avoid duplicate commands. |

| videoRoomId | string (UUID) | No | The ID of the video room you want to bridge with, can't be u... |

| ... | | | +16 optional params in references/api-details.md |

import com.telnyx.sdk.models.calls.actions.ActionBridgeParams;
import com.telnyx.sdk.models.calls.actions.ActionBridgeResponse;

ActionBridgeParams params = ActionBridgeParams.builder()
    .callControlIdToBridge("v3:550e8400-e29b-41d4-a716-446655440000_gRU1OGRkYQ")
    .callControlId("v3:MdI91X4lWFEs7IgbBEOT9M4AigoY08M0WWZFISt1Yw2axZ_IiE4pqg")
    .build();
ActionBridgeResponse response = client.calls().actions().bridge(params);

Primary response fields:

• response.data.result

Reject a call

Trigger a follow-up action in an existing workflow rather than creating a new top-level resource.

client.calls().actions().reject() — POST /calls/{call_control_id}/actions/reject

| Parameter | Type | Required | Description |

|-----------|------|----------|-------------|

| cause | enum (CALL_REJECTED, USER_BUSY) | Yes | Cause for call rejection. |

| callControlId | string (UUID) | Yes | Unique identifier and token for controlling the call |

| clientState | string | No | Use this field to add state to every subsequent webhook. |

| commandId | string (UUID) | No | Use this field to avoid duplicate commands. |

import com.telnyx.sdk.models.calls.actions.ActionRejectParams;
import com.telnyx.sdk.models.calls.actions.ActionRejectResponse;

ActionRejectParams params = ActionRejectParams.builder()
    .callControlId("v3:550e8400-e29b-41d4-a716-446655440000_gRU1OGRkYQ")
    .cause(ActionRejectParams.Cause.USER_BUSY)
    .build();
ActionRejectResponse response = client.calls().actions().reject(params);

Primary response fields:

• response.data.result

Retrieve a call status

Fetch the current state before updating, deleting, or making control-flow decisions.

client.calls().retrieveStatus() — GET /calls/{call_control_id}

| Parameter | Type | Required | Description |

|-----------|------|----------|-------------|

| callControlId | string (UUID) | Yes | Unique identifier and token for controlling the call |

import com.telnyx.sdk.models.calls.CallRetrieveStatusParams;
import com.telnyx.sdk.models.calls.CallRetrieveStatusResponse;

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

Primary response fields:

• response.data.callControlId
• response.data.callDuration
• response.data.callLegId
• response.data.callSessionId
• response.data.clientState
• response.data.endTime

List all active calls for given connection

Fetch the current state before updating, deleting, or making control-flow decisions.

client.connections().listActiveCalls() — GET /connections/{connection_id}/active_calls

| Parameter | Type | Required | Description |

|-----------|------|----------|-------------|

| connectionId | string (UUID) | Yes | Telnyx connection id |

| page | object | No | Consolidated page parameter (deepObject style). |

import com.telnyx.sdk.models.connections.ConnectionListActiveCallsPage;
import com.telnyx.sdk.models.connections.ConnectionListActiveCallsParams;

ConnectionListActiveCallsPage page = client.connections().listActiveCalls("1293384261075731461");

Response wrapper:

• items: page.data
• pagination: page.meta

Primary item fields:

• callControlId
• callDuration
• callLegId
• callSessionId
• clientState
• recordType

List call control applications

Inspect available resources or choose an existing resource before mutating it.

client.callControlApplications().list() — GET /call_control_applications

| Parameter | Type | Required | Description |

|-----------|------|----------|-------------|

| sort | enum (created_at, connection_name, active) | No | Specifies the sort order for results. |

| filter | object | No | Consolidated filter parameter (deepObject style). |

| page | object | No | Consolidated page parameter (deepObject style). |

import com.telnyx.sdk.models.callcontrolapplications.CallControlApplicationListPage;
import com.telnyx.sdk.models.callcontrolapplications.CallControlApplicationListParams;

CallControlApplicationListPage page = client.callControlApplications().list();

Response wrapper:

• items: page.data
• pagination: page.meta

Primary item fields:

• id
• createdAt
• updatedAt
• active
• anchorsiteOverride
• applicationName

Additional Operations

Use the core tasks above first. The operations below are indexed here with exact SDK methods and required params; use references/api-details.md for full optional params, response schemas, and lower-frequency webhook payloads.

Before using any operation below, read the optional-parameters section and the response-schemas section so you do not guess missing fields.

| Operation | SDK method | Endpoint | Use when | Required params |

|-----------|------------|----------|----------|-----------------|

| Create a call control application | client.callControlApplications().create() | POST /call_control_applications | Create or provision an additional resource when the core tasks do not cover this flow. | applicationName, webhookEventUrl |

| Retrieve a call control application | client.callControlApplications().retrieve() | GET /call_control_applications/{id} | Fetch the current state before updating, deleting, or making control-flow decisions. | id |

| Update a call control application | client.callControlApplications().update() | PATCH /call_control_applications/{id} | Modify an existing resource without recreating it. | applicationName, webhookEventUrl, id |

| Delete a call control application | client.callControlApplications().delete() | DELETE /call_control_applications/{id} | Remove, detach, or clean up an existing resource. | id |

| SIP Refer a call | client.calls().actions().refer() | POST /calls/{call_control_id}/actions/refer | Trigger a follow-up action in an existing workflow rather than creating a new top-level resource. | sipAddress, callControlId |

| Send SIP info | client.calls().actions().sendSipInfo() | POST /calls/{call_control_id}/actions/send_sip_info | Trigger a follow-up action in an existing workflow rather than creating a new top-level resource. | contentType, body, callControlId |

Other Webhook Events

| Event | data.event_type | Description |

|-------|-------------------|-------------|

| callBridged | call.bridged | Call Bridged |

For exhaustive optional parameters, full response schemas, and complete webhook payloads, see references/api-details.md.