The Nuntly Java SDK provides convenient access to the Nuntly REST API from applications written in Java.
It is generated with Stainless.
Use the Nuntly MCP Server to enable AI assistants to interact with this API, allowing them to explore endpoints, make test requests, and use documentation to help integrate this SDK into your application.
Note: You may need to set environment variables in your MCP client.
The REST API documentation can be found on developers.nuntly.com. Javadocs are available on javadoc.io.
implementation("com.nuntly:nuntly-java:0.5.0")<dependency>
<groupId>com.nuntly</groupId>
<artifactId>nuntly-java</artifactId>
<version>0.5.0</version>
</dependency>This library requires Java 8 or later.
import com.nuntly.client.NuntlyClient;
import com.nuntly.client.okhttp.NuntlyOkHttpClient;
import com.nuntly.models.emails.EmailSendParams;
import com.nuntly.models.emails.EmailSendResponse;
// Configures using the `nuntly.apiKey` and `nuntly.baseUrl` system properties
// Or configures using the `NUNTLY_API_KEY` and `NUNTLY_BASE_URL` environment variables
NuntlyClient client = NuntlyOkHttpClient.fromEnv();
EmailSendParams params = EmailSendParams.builder()
.from("ray@info.tomlinson.ai")
.subject("Verify Your Email Address")
.to("brian67@gmail.com")
.text("Thank you for signing up! Please verify your email address...")
.build();
EmailSendResponse email = client.emails().send(params);Configure the client using system properties or environment variables:
import com.nuntly.client.NuntlyClient;
import com.nuntly.client.okhttp.NuntlyOkHttpClient;
// Configures using the `nuntly.apiKey` and `nuntly.baseUrl` system properties
// Or configures using the `NUNTLY_API_KEY` and `NUNTLY_BASE_URL` environment variables
NuntlyClient client = NuntlyOkHttpClient.fromEnv();Or manually:
import com.nuntly.client.NuntlyClient;
import com.nuntly.client.okhttp.NuntlyOkHttpClient;
NuntlyClient client = NuntlyOkHttpClient.builder()
.apiKey("My API Key")
.build();Or using a combination of the two approaches:
import com.nuntly.client.NuntlyClient;
import com.nuntly.client.okhttp.NuntlyOkHttpClient;
NuntlyClient client = NuntlyOkHttpClient.builder()
// Configures using the `nuntly.apiKey` and `nuntly.baseUrl` system properties
// Or configures using the `NUNTLY_API_KEY` and `NUNTLY_BASE_URL` environment variables
.fromEnv()
.apiKey("My API Key")
.build();See this table for the available options:
| Setter | System property | Environment variable | Required | Default value |
|---|---|---|---|---|
apiKey |
nuntly.apiKey |
NUNTLY_API_KEY |
false | - |
baseUrl |
nuntly.baseUrl |
NUNTLY_BASE_URL |
true | "https://api.nuntly.com" |
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.
To temporarily use a modified client configuration, while reusing the same connection and thread pools, call withOptions() on any client or service:
import com.nuntly.client.NuntlyClient;
NuntlyClient clientWithOptions = client.withOptions(optionsBuilder -> {
optionsBuilder.baseUrl("https://example.com");
optionsBuilder.maxRetries(42);
});The withOptions() method does not affect the original client or service.
To send a request to the Nuntly 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.emails().send(...) should be called with an instance of EmailSendParams, and it will return an instance of EmailSendResponse.
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.
The default client is synchronous. To switch to asynchronous execution, call the async() method:
import com.nuntly.client.NuntlyClient;
import com.nuntly.client.okhttp.NuntlyOkHttpClient;
import com.nuntly.models.emails.EmailSendParams;
import com.nuntly.models.emails.EmailSendResponse;
import java.util.concurrent.CompletableFuture;
// Configures using the `nuntly.apiKey` and `nuntly.baseUrl` system properties
// Or configures using the `NUNTLY_API_KEY` and `NUNTLY_BASE_URL` environment variables
NuntlyClient client = NuntlyOkHttpClient.fromEnv();
EmailSendParams params = EmailSendParams.builder()
.from("ray@info.tomlinson.ai")
.subject("Verify Your Email Address")
.to("brian67@gmail.com")
.text("Thank you for signing up! Please verify your email address...")
.build();
CompletableFuture<EmailSendResponse> email = client.async().emails().send(params);Or create an asynchronous client from the beginning:
import com.nuntly.client.NuntlyClientAsync;
import com.nuntly.client.okhttp.NuntlyOkHttpClientAsync;
import com.nuntly.models.emails.EmailSendParams;
import com.nuntly.models.emails.EmailSendResponse;
import java.util.concurrent.CompletableFuture;
// Configures using the `nuntly.apiKey` and `nuntly.baseUrl` system properties
// Or configures using the `NUNTLY_API_KEY` and `NUNTLY_BASE_URL` environment variables
NuntlyClientAsync client = NuntlyOkHttpClientAsync.fromEnv();
EmailSendParams params = EmailSendParams.builder()
.from("ray@info.tomlinson.ai")
.subject("Verify Your Email Address")
.to("brian67@gmail.com")
.text("Thank you for signing up! Please verify your email address...")
.build();
CompletableFuture<EmailSendResponse> email = client.emails().send(params);The asynchronous client supports the same options as the synchronous one, except most methods return CompletableFutures.
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.nuntly.core.http.Headers;
import com.nuntly.core.http.HttpResponseFor;
import com.nuntly.models.apikeys.ApiKeyCreateParams;
import com.nuntly.models.apikeys.ApiKeyCreateResponse;
HttpResponseFor<ApiKeyCreateResponse> apiKey = client.apiKeys().withRawResponse().create();
int statusCode = apiKey.statusCode();
Headers headers = apiKey.headers();You can still deserialize the response into an instance of a Java class if needed:
import com.nuntly.models.apikeys.ApiKeyCreateResponse;
ApiKeyCreateResponse parsedApiKey = apiKey.parse();The SDK throws custom unchecked exception types:
-
NuntlyServiceException: Base class for HTTP errors. See this table for which exception subclass is thrown for each HTTP status code:Status Exception 400 BadRequestException401 UnauthorizedException403 PermissionDeniedException404 NotFoundException422 UnprocessableEntityException429 RateLimitException5xx InternalServerExceptionothers UnexpectedStatusCodeException -
NuntlyIoException: I/O networking errors. -
NuntlyRetryableException: Generic error indicating a failure that could be retried by the client. -
NuntlyInvalidDataException: Failure to interpret successfully parsed data. For example, when accessing a property that's supposed to be required, but the API unexpectedly omitted it from the response. -
NuntlyException: Base class for all exceptions. Most errors will result in one of the previously mentioned ones, but completely generic errors may be thrown using the base class.
The SDK defines methods that return a paginated lists of results. It provides convenient ways to access the results either one page at a time or item-by-item across all pages.
To iterate through all results across all pages, use the autoPager() method, which automatically fetches more pages as needed.
When using the synchronous client, the method returns an Iterable
import com.nuntly.models.emails.EmailListPage;
import com.nuntly.models.emails.EmailListResponse;
EmailListPage page = client.emails().list();
// Process as an Iterable
for (EmailListResponse email : page.autoPager()) {
System.out.println(email);
}
// Process as a Stream
page.autoPager()
.stream()
.limit(50)
.forEach(email -> System.out.println(email));When using the asynchronous client, the method returns an AsyncStreamResponse:
import com.nuntly.core.http.AsyncStreamResponse;
import com.nuntly.models.emails.EmailListPageAsync;
import com.nuntly.models.emails.EmailListResponse;
import java.util.Optional;
import java.util.concurrent.CompletableFuture;
CompletableFuture<EmailListPageAsync> pageFuture = client.async().emails().list();
pageFuture.thenRun(page -> page.autoPager().subscribe(email -> {
System.out.println(email);
}));
// If you need to handle errors or completion of the stream
pageFuture.thenRun(page -> page.autoPager().subscribe(new AsyncStreamResponse.Handler<>() {
@Override
public void onNext(EmailListResponse email) {
System.out.println(email);
}
@Override
public void onComplete(Optional<Throwable> error) {
if (error.isPresent()) {
System.out.println("Something went wrong!");
throw new RuntimeException(error.get());
} else {
System.out.println("No more!");
}
}
}));
// Or use futures
pageFuture.thenRun(page -> page.autoPager()
.subscribe(email -> {
System.out.println(email);
})
.onCompleteFuture()
.whenComplete((unused, error) -> {
if (error != null) {
System.out.println("Something went wrong!");
throw new RuntimeException(error);
} else {
System.out.println("No more!");
}
}));To access individual page items and manually request the next page, use the items(),
hasNextPage(), and nextPage() methods:
import com.nuntly.models.emails.EmailListPage;
import com.nuntly.models.emails.EmailListResponse;
EmailListPage page = client.emails().list();
while (true) {
for (EmailListResponse email : page.items()) {
System.out.println(email);
}
if (!page.hasNextPage()) {
break;
}
page = page.nextPage();
}The SDK uses the standard OkHttp logging interceptor.
Enable logging by setting the NUNTLY_LOG environment variable to info:
export NUNTLY_LOG=infoOr to debug for more verbose logging:
export NUNTLY_LOG=debugAlthough the SDK uses reflection, it is still usable with ProGuard and R8 because nuntly-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.
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 NuntlyOkHttpClient or NuntlyOkHttpClientAsync.
Caution
We make no guarantee that the SDK works correctly when the Jackson version check is disabled.
Also note that there are bugs in older Jackson versions that can affect the SDK. We don't work around all Jackson bugs (example) and expect users to upgrade Jackson for those instead.
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.nuntly.client.NuntlyClient;
import com.nuntly.client.okhttp.NuntlyOkHttpClient;
NuntlyClient client = NuntlyOkHttpClient.builder()
.fromEnv()
.maxRetries(4)
.build();Requests time out after 1 minute by default.
To set a custom timeout, configure the method call using the timeout method:
import com.nuntly.models.apikeys.ApiKeyCreateResponse;
ApiKeyCreateResponse apiKey = client.apiKeys().create(RequestOptions.builder().timeout(Duration.ofSeconds(30)).build());Or configure the default for all method calls at the client level:
import com.nuntly.client.NuntlyClient;
import com.nuntly.client.okhttp.NuntlyOkHttpClient;
import java.time.Duration;
NuntlyClient client = NuntlyOkHttpClient.builder()
.fromEnv()
.timeout(Duration.ofSeconds(30))
.build();To route requests through a proxy, configure the client using the proxy method:
import com.nuntly.client.NuntlyClient;
import com.nuntly.client.okhttp.NuntlyOkHttpClient;
import java.net.InetSocketAddress;
import java.net.Proxy;
NuntlyClient client = NuntlyOkHttpClient.builder()
.fromEnv()
.proxy(new Proxy(
Proxy.Type.HTTP, new InetSocketAddress(
"https://example.com", 8080
)
))
.build();To customize the underlying OkHttp connection pool, configure the client using the maxIdleConnections and keepAliveDuration methods:
import com.nuntly.client.NuntlyClient;
import com.nuntly.client.okhttp.NuntlyOkHttpClient;
import java.time.Duration;
NuntlyClient client = NuntlyOkHttpClient.builder()
.fromEnv()
// If `maxIdleConnections` is set, then `keepAliveDuration` must be set, and vice versa.
.maxIdleConnections(10)
.keepAliveDuration(Duration.ofMinutes(2))
.build();If both options are unset, OkHttp's default connection pool settings are used.
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.nuntly.client.NuntlyClient;
import com.nuntly.client.okhttp.NuntlyOkHttpClient;
NuntlyClient client = NuntlyOkHttpClient.builder()
.fromEnv()
// If `sslSocketFactory` is set, then `trustManager` must be set, and vice versa.
.sslSocketFactory(yourSSLSocketFactory)
.trustManager(yourTrustManager)
.hostnameVerifier(yourHostnameVerifier)
.build();The SDK consists of three artifacts:
nuntly-java-core- Contains core SDK logic
- Does not depend on OkHttp
- Exposes
NuntlyClient,NuntlyClientAsync,NuntlyClientImpl, andNuntlyClientAsyncImpl, all of which can work with any HTTP client
nuntly-java-client-okhttp- Depends on OkHttp
- Exposes
NuntlyOkHttpClientandNuntlyOkHttpClientAsync, which provide a way to constructNuntlyClientImplandNuntlyClientAsyncImpl, respectively, using OkHttp
nuntly-java- Depends on and exposes the APIs of both
nuntly-java-coreandnuntly-java-client-okhttp - Does not have its own logic
- Depends on and exposes the APIs of both
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:
- Replace your
nuntly-javadependency withnuntly-java-core - Copy
nuntly-java-client-okhttp'sOkHttpClientclass into your code and customize it - Construct
NuntlyClientImplorNuntlyClientAsyncImpl, similarly toNuntlyOkHttpClientorNuntlyOkHttpClientAsync, using your customized client
To use a completely custom HTTP client:
- Replace your
nuntly-javadependency withnuntly-java-core - Write a class that implements the
HttpClientinterface - Construct
NuntlyClientImplorNuntlyClientAsyncImpl, similarly toNuntlyOkHttpClientorNuntlyOkHttpClientAsync, using your new client class
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.
To set undocumented parameters, call the putAdditionalHeader, putAdditionalQueryParam, or putAdditionalBodyProperty methods on any Params class:
import com.nuntly.core.JsonValue;
import com.nuntly.models.emails.EmailSendParams;
EmailSendParams params = EmailSendParams.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.nuntly.core.JsonValue;
import com.nuntly.models.emails.bulk.BulkSendParams;
BulkSendParams params = BulkSendParams.builder()
.fallback(BulkSendParams.Fallback.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.nuntly.core.JsonValue;
import com.nuntly.models.emails.EmailSendParams;
EmailSendParams params = EmailSendParams.builder()
.from(JsonValue.from(42))
.subject("Verify Your Email Address")
.to("brian67@gmail.com")
.text("Thank you for signing up! Please verify your email address...")
.build();The most straightforward way to create a JsonValue is using its from(...) method:
import com.nuntly.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.nuntly.core.JsonMissing;
import com.nuntly.models.emails.EmailSendParams;
EmailSendParams params = EmailSendParams.builder()
.subject("Verify your email address")
.to("brian67@gmail.com")
.from(JsonMissing.of())
.build();To access undocumented response properties, call the _additionalProperties() method:
import com.nuntly.core.JsonValue;
import java.util.Map;
Map<String, JsonValue> additionalProperties = client.emails().send(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.nuntly.core.JsonField;
import java.util.Optional;
JsonField<String> from = client.emails().send(params)._from();
if (from.isMissing()) {
// The property is absent from the JSON response
} else if (from.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 = from.asString();
// Try to deserialize into a custom type
MyClass myObject = from.asUnknown().orElseThrow().convert(MyClass.class);
}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 NuntlyInvalidDataException 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.nuntly.models.emails.EmailSendResponse;
EmailSendResponse email = client.emails().send(params).validate();Or configure the method call to validate the response using the responseValidation method:
import com.nuntly.models.emails.EmailSendResponse;
EmailSendResponse email = client.emails().send(
params, RequestOptions.builder().responseValidation(true).build()
);Or configure the default for all method calls at the client level:
import com.nuntly.client.NuntlyClient;
import com.nuntly.client.okhttp.NuntlyOkHttpClient;
NuntlyClient client = NuntlyOkHttpClient.builder()
.fromEnv()
.responseValidation(true)
.build();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.
Using JsonField<T> enables a few features:
- Allowing usage of undocumented API functionality
- Lazily validating the API response against the expected shape
- Representing absent vs explicitly null values
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.
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)
This package generally follows SemVer conventions, though certain backwards-incompatible changes may be released as minor versions:
- 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.)
- 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.