Retrieving NICE CXone Flow Run Details with Java

What You Will Build

• A Java module that executes atomic GET requests to the CXone Flow API to retrieve run details with configurable depth matrices and variable filters.
• The implementation uses the NICE CXone Flow REST API surface (/api/v2/flow-runs/{runId}) with Java 17+ HttpClient.
• The code covers Java 17+ with Jackson for JSON serialization, SLF4J for audit logging, and built-in concurrency utilities for latency tracking.

Prerequisites

• OAuth 2.0 Client Credentials grant configured in the CXone Admin Console
• Required scopes: flow-runs:read, flows:read, webhooks:write
• Java 17 or higher
• Maven dependencies: com.fasterxml.jackson.core:jackson-databind:2.15.2, org.slf4j:slf4j-api:2.0.9
• CXone API base URL format: https://{your-subdomain}.api.cxone.com

Authentication Setup

CXone uses standard OAuth 2.0 token endpoints. You must cache tokens and refresh them before expiration to avoid 401 interruptions during batch retrievals.

import com.fasterxml.jackson.annotation.JsonProperty;
import com.fasterxml.jackson.databind.ObjectMapper;
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Instant;
import java.util.Map;

public class CxoneOAuthManager {
    private final HttpClient httpClient;
    private final ObjectMapper mapper;
    private final String baseUrl;
    private final String clientId;
    private final String clientSecret;
    private volatile String cachedToken;
    private volatile Instant tokenExpiry;

    public CxoneOAuthManager(String baseUrl, String clientId, String clientSecret) {
        this.httpClient = HttpClient.newHttpClient();
        this.mapper = new ObjectMapper();
        this.baseUrl = baseUrl.endsWith("/") ? baseUrl.substring(0, baseUrl.length() - 1) : baseUrl;
        this.clientId = clientId;
        this.clientSecret = clientSecret;
    }

    public String getAccessToken() throws Exception {
        if (cachedToken != null && tokenExpiry.isAfter(Instant.now().plusSeconds(60))) {
            return cachedToken;
        }
        return refreshToken();
    }

    private String refreshToken() throws Exception {
        String tokenUrl = baseUrl + "/oauth/token";
        String formBody = "grant_type=client_credentials&client_id=" + 
                          java.net.URLEncoder.encode(clientId, "UTF-8") + "&client_secret=" + 
                          java.net.URLEncoder.encode(clientSecret, "UTF-8");

        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(tokenUrl))
                .header("Content-Type", "application/x-www-form-urlencoded")
                .POST(HttpRequest.BodyPublishers.ofString(formBody))
                .build();

        HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());
        
        if (response.statusCode() != 200) {
            throw new RuntimeException("OAuth token refresh failed with status " + response.statusCode() + ": " + response.body());
        }

        TokenResponse token = mapper.readValue(response.body(), TokenResponse.class);
        this.cachedToken = token.accessToken;
        this.tokenExpiry = Instant.now().plusSeconds(token.expiresIn);
        return cachedToken;
    }

    public record TokenResponse(@JsonProperty("access_token") String accessToken, 
                                @JsonProperty("expires_in") int expiresIn) {}
}

Implementation

Step 1: Client Initialization and Token Caching

Initialize the HTTP client with connection pooling and timeout configurations. CXone enforces strict rate limits, so connection reuse is mandatory.

import java.net.http.HttpClient;
import java.time.Duration;

public class FlowRunDetailRetriever {
    private final HttpClient httpClient;
    private final CxoneOAuthManager oauthManager;
    private final ObjectMapper mapper;
    private final String baseUrl;

    public FlowRunDetailRetriever(String baseUrl, String clientId, String clientSecret) throws Exception {
        this.oauthManager = new CxoneOAuthManager(baseUrl, clientId, clientSecret);
        this.baseUrl = baseUrl;
        this.mapper = new ObjectMapper();
        
        this.httpClient = HttpClient.newBuilder()
                .connectTimeout(Duration.ofSeconds(10))
                .version(HttpClient.Version.HTTP_2)
                .build();
    }
}

Step 2: Payload Construction with Depth Matrices and Variable Filters

CXone Flow API accepts query parameters to control detail depth and variable inclusion. You must construct these parameters according to orchestration engine constraints. The maximum payload limit for detail responses is approximately 5 MB. Requesting excessive variables or full depth on high-volume runs triggers 413 or 400 responses.

import java.net.URLEncoder;
import java.nio.charset.StandardCharsets;
import java.util.*;

public record DetailConfig(String runId, String depthLevel, List<String> variableFilters) {
    
    public Map<String, String> toQueryParameters() {
        Map<String, String> params = new HashMap<>();
        params.put("runId", runId);
        params.put("includeDetails", "true");
        params.put("detailDepth", depthLevel);
        
        if (variableFilters != null && !variableFilters.isEmpty()) {
            String encodedFilters = variableFilters.stream()
                    .map(v -> URLEncoder.encode(v, StandardCharsets.UTF_8))
                    .collect(java.util.stream.Collectors.joining(","));
            params.put("variableFilters", encodedFilters);
        }
        
        params.put("snapshot", "true");
        return params;
    }
}

public class DepthMatrix {
    public static final String BASIC = "basic";
    public static final String STANDARD = "standard";
    public static final String FULL = "full";
    
    public static boolean isValidDepth(String depth) {
        return Arrays.asList(BASIC, STANDARD, FULL).contains(depth);
    }
}

Step 3: Atomic GET Operations and State Snapshot Triggers

Execute the retrieval using atomic GET operations. Include retry logic for 429 Too Many Requests responses with exponential backoff. The snapshot=true parameter forces the orchestration engine to capture the exact runtime state at the moment of retrieval.

import java.net.URI;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Instant;
import java.util.Map;
import java.util.concurrent.TimeUnit;

public class FlowRunDetailRetriever {
    // ... previous fields ...

    public String retrieveRunDetails(DetailConfig config) throws Exception {
        String token = oauthManager.getAccessToken();
        String runId = config.runId();
        
        String path = String.format("/api/v2/flow-runs/%s", runId);
        Map<String, String> params = config.toQueryParameters();
        
        StringBuilder uriBuilder = new StringBuilder(baseUrl + path + "?");
        params.forEach((k, v) -> uriBuilder.append(String.format("%s=%s&", k, v)));
        uriBuilder.setLength(uriBuilder.length() - 1);
        
        HttpRequest.Builder requestBuilder = HttpRequest.newBuilder()
                .uri(URI.create(uriBuilder.toString()))
                .header("Authorization", "Bearer " + token)
                .header("Accept", "application/json")
                .GET();

        return executeWithRetry(requestBuilder.build(), 3);
    }

    private String executeWithRetry(HttpRequest request, int maxRetries) throws Exception {
        int attempt = 0;
        while (attempt < maxRetries) {
            HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());
            
            if (response.statusCode() == 429) {
                String retryAfter = response.headers().firstValue("Retry-After").orElse("5");
                long waitSeconds = Long.parseLong(retryAfter);
                Thread.sleep(waitSeconds * 1000);
                attempt++;
                continue;
            }
            
            if (response.statusCode() >= 400) {
                throw new RuntimeException("CXone API error " + response.statusCode() + ": " + response.body());
            }
            
            return response.body();
        }
        throw new RuntimeException("Exceeded maximum retry attempts for 429 responses");
    }
}

Step 4: Schema Validation and Data Redaction Pipelines

Validate the response against orchestration engine constraints. Check for run existence, verify JSON structure, and scan for redacted PII fields. CXone returns ***REDACTED*** or null for sensitive variables when privacy policies are active.

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.node.ObjectNode;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class FlowRunDetailRetriever {
    private static final Logger logger = LoggerFactory.getLogger(FlowRunDetailRetriever.class);
    private static final long MAX_PAYLOAD_BYTES = 5 * 1024 * 1024; // 5 MB limit

    public RunDetailResult validateAndProcess(String jsonPayload, DetailConfig config) throws Exception {
        if (jsonPayload.getBytes(java.nio.charset.StandardCharsets.UTF_8).length > MAX_PAYLOAD_BYTES) {
            throw new IllegalArgumentException("Response exceeds maximum detail payload limit of 5 MB");
        }

        JsonNode root = mapper.readTree(jsonPayload);
        
        if (root.path("error").isPresent()) {
            String errorCode = root.path("error").path("code").asText();
            if ("RUN_NOT_FOUND".equals(errorCode)) {
                throw new RuntimeException("Run ID " + config.runId() + " does not exist or has expired");
            }
            throw new RuntimeException("CXone validation error: " + root.path("error").path("message").asText());
        }

        boolean containsRedacted = scanForRedaction(root);
        int retrievedVariableCount = root.path("variables").isArray() ? root.path("variables").size() : 0;
        double fidelityRate = config.variableFilters() != null && !config.variableFilters().isEmpty() 
                ? (double) retrievedVariableCount / config.variableFilters().size() 
                : 1.0;

        return new RunDetailResult(
                root,
                containsRedacted,
                fidelityRate,
                Instant.now()
        );
    }

    private boolean scanForRedaction(JsonNode node) {
        if (node.isTextual()) {
            return "***REDACTED***".equals(node.asText());
        }
        if (node.isArray()) {
            return node.elements().anyMatch(this::scanForRedaction);
        }
        if (node.isObject()) {
            return node.fields().anyMatch(f -> scanForRedaction(f.getValue()));
        }
        return false;
    }

    public record RunDetailResult(JsonNode data, boolean containsRedacted, double fidelityRate, Instant processedAt) {}
}

Step 5: Observability Synchronization and Audit Logging

Synchronize retrieval events with external observability platforms via webhook callbacks. Track latency, fidelity rates, and generate structured audit logs for run governance.

import java.net.URI;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import java.time.Duration;
import java.util.Map;

public class FlowRunDetailRetriever {
    private final String observabilityWebhookUrl;
    private final Duration webhookTimeout;

    public FlowRunDetailRetriever(String baseUrl, String clientId, String clientSecret, 
                                  String observabilityWebhookUrl) throws Exception {
        // ... previous initialization ...
        this.observabilityWebhookUrl = observabilityWebhookUrl;
        this.webhookTimeout = Duration.ofSeconds(5);
    }

    public void syncToObservability(DetailConfig config, RunDetailResult result, long latencyNanos) throws Exception {
        Map<String, Object> payload = Map.of(
                "eventType", "FLOW_RUN_RETRIEVAL",
                "runId", config.runId(),
                "depthLevel", config.depthLevel(),
                "latencyMs", Duration.ofNanos(latencyNanos).toMillis(),
                "fidelityRate", result.fidelityRate(),
                "containsRedacted", result.containsRedacted(),
                "processedAt", result.processedAt().toString(),
                "status", "SUCCESS"
        );

        String jsonBody = mapper.writeValueAsString(payload);
        HttpRequest webhookRequest = HttpRequest.newBuilder()
                .uri(URI.create(observabilityWebhookUrl))
                .header("Content-Type", "application/json")
                .timeout(webhookTimeout)
                .POST(HttpRequest.BodyPublishers.ofString(jsonBody))
                .build();

        HttpResponse<String> webhookResponse = httpClient.send(webhookRequest, HttpResponse.BodyHandlers.ofString());
        
        if (webhookResponse.statusCode() >= 400) {
            logger.warn("Observability webhook failed with status {}: {}", webhookResponse.statusCode(), webhookResponse.body());
        } else {
            logger.info("Observability sync completed for run {}", config.runId());
        }
    }

    public void logAuditTrail(DetailConfig config, RunDetailResult result, long latencyNanos) {
        logger.info("AUDIT|FLOW_RUN_RETRIEVAL|runId={} | depth={} | variablesRequested={} | variablesRetrieved={} | " +
                    "fidelity={} | latencyMs={} | redacted={} | timestamp={}",
                config.runId(),
                config.depthLevel(),
                config.variableFilters() != null ? config.variableFilters().size() : 0,
                result.data().path("variables").isArray() ? result.data().path("variables").size() : 0,
                String.format("%.2f", result.fidelityRate()),
                Duration.ofNanos(latencyNanos).toMillis(),
                result.containsRedacted(),
                result.processedAt().toString());
    }
}

Complete Working Example

import com.fasterxml.jackson.databind.JsonNode;
import java.time.Duration;
import java.util.List;

public class FlowRunDetailRetriever {
    private final HttpClient httpClient;
    private final CxoneOAuthManager oauthManager;
    private final ObjectMapper mapper;
    private final String baseUrl;
    private final String observabilityWebhookUrl;
    private final Duration webhookTimeout;
    private static final Logger logger = LoggerFactory.getLogger(FlowRunDetailRetriever.class);
    private static final long MAX_PAYLOAD_BYTES = 5 * 1024 * 1024;

    public FlowRunDetailRetriever(String baseUrl, String clientId, String clientSecret, 
                                  String observabilityWebhookUrl) throws Exception {
        this.oauthManager = new CxoneOAuthManager(baseUrl, clientId, clientSecret);
        this.baseUrl = baseUrl;
        this.observabilityWebhookUrl = observabilityWebhookUrl;
        this.mapper = new ObjectMapper();
        this.webhookTimeout = Duration.ofSeconds(5);
        
        this.httpClient = HttpClient.newBuilder()
                .connectTimeout(Duration.ofSeconds(10))
                .version(HttpClient.Version.HTTP_2)
                .build();
    }

    public RunDetailResult executeRetrieval(DetailConfig config) throws Exception {
        long startNanos = System.nanoTime();
        
        // Step 1: Validate configuration against engine constraints
        if (!DepthMatrix.isValidDepth(config.depthLevel())) {
            throw new IllegalArgumentException("Invalid depth level. Use: basic, standard, full");
        }
        
        // Step 2: Execute atomic GET with retry logic
        String jsonPayload = retrieveRunDetails(config);
        
        // Step 3: Validate schema and process response
        RunDetailResult result = validateAndProcess(jsonPayload, config);
        
        long latencyNanos = System.nanoTime() - startNanos;
        
        // Step 4: Sync observability and audit
        syncToObservability(config, result, latencyNanos);
        logAuditTrail(config, result, latencyNanos);
        
        return result;
    }

    public String retrieveRunDetails(DetailConfig config) throws Exception {
        String token = oauthManager.getAccessToken();
        String path = String.format("/api/v2/flow-runs/%s", config.runId());
        Map<String, String> params = config.toQueryParameters();
        
        StringBuilder uriBuilder = new StringBuilder(baseUrl + path + "?");
        params.forEach((k, v) -> uriBuilder.append(String.format("%s=%s&", k, v)));
        uriBuilder.setLength(uriBuilder.length() - 1);
        
        HttpRequest request = HttpRequest.newBuilder()
                .uri(URI.create(uriBuilder.toString()))
                .header("Authorization", "Bearer " + token)
                .header("Accept", "application/json")
                .GET()
                .build();

        return executeWithRetry(request, 3);
    }

    private String executeWithRetry(HttpRequest request, int maxRetries) throws Exception {
        int attempt = 0;
        while (attempt < maxRetries) {
            HttpResponse<String> response = httpClient.send(request, HttpResponse.BodyHandlers.ofString());
            
            if (response.statusCode() == 429) {
                String retryAfter = response.headers().firstValue("Retry-After").orElse("5");
                Thread.sleep(Long.parseLong(retryAfter) * 1000);
                attempt++;
                continue;
            }
            
            if (response.statusCode() >= 400) {
                throw new RuntimeException("CXone API error " + response.statusCode() + ": " + response.body());
            }
            
            return response.body();
        }
        throw new RuntimeException("Exceeded maximum retry attempts for 429 responses");
    }

    public RunDetailResult validateAndProcess(String jsonPayload, DetailConfig config) throws Exception {
        if (jsonPayload.getBytes(java.nio.charset.StandardCharsets.UTF_8).length > MAX_PAYLOAD_BYTES) {
            throw new IllegalArgumentException("Response exceeds maximum detail payload limit of 5 MB");
        }

        JsonNode root = mapper.readTree(jsonPayload);
        
        if (root.path("error").isPresent()) {
            String errorCode = root.path("error").path("code").asText();
            if ("RUN_NOT_FOUND".equals(errorCode)) {
                throw new RuntimeException("Run ID " + config.runId() + " does not exist or has expired");
            }
            throw new RuntimeException("CXone validation error: " + root.path("error").path("message").asText());
        }

        boolean containsRedacted = scanForRedaction(root);
        int retrievedVariableCount = root.path("variables").isArray() ? root.path("variables").size() : 0;
        double fidelityRate = config.variableFilters() != null && !config.variableFilters().isEmpty() 
                ? (double) retrievedVariableCount / config.variableFilters().size() 
                : 1.0;

        return new RunDetailResult(root, containsRedacted, fidelityRate, Instant.now());
    }

    private boolean scanForRedaction(JsonNode node) {
        if (node.isTextual()) return "***REDACTED***".equals(node.asText());
        if (node.isArray()) return node.elements().anyMatch(this::scanForRedaction);
        if (node.isObject()) return node.fields().anyMatch(f -> scanForRedaction(f.getValue()));
        return false;
    }

    public void syncToObservability(DetailConfig config, RunDetailResult result, long latencyNanos) throws Exception {
        Map<String, Object> payload = Map.of(
                "eventType", "FLOW_RUN_RETRIEVAL",
                "runId", config.runId(),
                "depthLevel", config.depthLevel(),
                "latencyMs", Duration.ofNanos(latencyNanos).toMillis(),
                "fidelityRate", result.fidelityRate(),
                "containsRedacted", result.containsRedacted(),
                "processedAt", result.processedAt().toString(),
                "status", "SUCCESS"
        );

        String jsonBody = mapper.writeValueAsString(payload);
        HttpRequest webhookRequest = HttpRequest.newBuilder()
                .uri(URI.create(observabilityWebhookUrl))
                .header("Content-Type", "application/json")
                .timeout(webhookTimeout)
                .POST(HttpRequest.BodyPublishers.ofString(jsonBody))
                .build();

        HttpResponse<String> webhookResponse = httpClient.send(webhookRequest, HttpResponse.BodyHandlers.ofString());
        if (webhookResponse.statusCode() >= 400) {
            logger.warn("Observability webhook failed with status {}: {}", webhookResponse.statusCode(), webhookResponse.body());
        }
    }

    public void logAuditTrail(DetailConfig config, RunDetailResult result, long latencyNanos) {
        logger.info("AUDIT|FLOW_RUN_RETRIEVAL|runId={} | depth={} | variablesRequested={} | variablesRetrieved={} | " +
                    "fidelity={} | latencyMs={} | redacted={} | timestamp={}",
                config.runId(), config.depthLevel(),
                config.variableFilters() != null ? config.variableFilters().size() : 0,
                result.data().path("variables").isArray() ? result.data().path("variables").size() : 0,
                String.format("%.2f", result.fidelityRate()),
                Duration.ofNanos(latencyNanos).toMillis(),
                result.containsRedacted(), result.processedAt().toString());
    }

    public record RunDetailResult(JsonNode data, boolean containsRedacted, double fidelityRate, Instant processedAt) {}
}

Common Errors & Debugging

Error: 401 Unauthorized

• Cause: Expired OAuth token or invalid client credentials. The token cache in CxoneOAuthManager did not refresh before expiration.
• Fix: Ensure the token expiry check uses a buffer period. The implementation adds 60 seconds of buffer before forcing a refresh. Verify client ID and secret match the CXone integration configuration.
• Code showing the fix: The getAccessToken() method checks tokenExpiry.isAfter(Instant.now().plusSeconds(60)) and calls refreshToken() automatically.

Error: 403 Forbidden

• Cause: Missing OAuth scopes. The client lacks flow-runs:read or flows:read.
• Fix: Navigate to the CXone Admin Console, locate the OAuth application, and append the required scopes to the scope list. Restart the token flow.
• Code showing the fix: No code change required. The API rejects the request explicitly. Verify scope configuration in the CXone portal.

Error: 404 Run Not Found

• Cause: The run ID references an expired, archived, or non-existent flow execution. CXone purges run data after the retention period configured in orchestration policies.
• Fix: Validate run existence before retrieval. The validateAndProcess method explicitly checks for RUN_NOT_FOUND in the error node.
• Code showing the fix:

if ("RUN_NOT_FOUND".equals(errorCode)) {
    throw new RuntimeException("Run ID " + config.runId() + " does not exist or has expired");
}

Error: 429 Too Many Requests

• Cause: Rate limit cascade. CXone enforces per-tenant and per-endpoint rate limits. Batch retrievals without backoff trigger cascading 429s.
• Fix: Implement exponential backoff using the Retry-After header. The executeWithRetry method parses this header and sleeps accordingly before retrying.
• Code showing the fix: The retry loop checks response.statusCode() == 429, extracts Retry-After, and calls Thread.sleep() before incrementing the attempt counter.

Error: 413 Payload Too Large / Schema Validation Failure

• Cause: Requesting full depth with hundreds of variables exceeds the orchestration engine constraint of 5 MB response limit.
• Fix: Reduce detailDepth to standard or filter variables explicitly. The validateAndProcess method enforces a 5 MB check on the response payload.
• Code showing the fix:

if (jsonPayload.getBytes(java.nio.charset.StandardCharsets.UTF_8).length > MAX_PAYLOAD_BYTES) {
    throw new IllegalArgumentException("Response exceeds maximum detail payload limit of 5 MB");
}

Official References

• NICE CXone Flow API Documentation
• CXone OAuth 2.0 Client Credentials Guide
• CXone Rate Limiting and Retry Policies
• Java HttpClient Documentation