# Java client documentation ## Set up the client ### Install the client The `notifications-java-client` deploys to Maven Central. Go to the [Notify Java client page on Maven Central](https://search.maven.org/artifact/uk.gov.service.notify/notifications-java-client): 1. Select the most recent version. 2. Copy the dependency configuration snippet for your build tool. Refer to the [client changelog](https://github.com/alphagov/notifications-java-client/blob/main/CHANGELOG.md) for the version number and the latest updates. ### Create a new instance of the client Add this code to your application: ```java import uk.gov.service.notify.NotificationClient; NotificationClient client = new NotificationClient(apiKey, "https://api.notifynl.nl"); ``` To get an API key, [sign in to NotifyNL](https://admin.notifynl.nl/sign-in) and go to the **API integration** page. You can find more information in the API keys section of this documentation. **Connect through a proxy (optional)** If you use a proxy you can pass it into the NotificationClient constructor. ```java import uk.gov.service.notify.NotificationClient; NotificationClient client = new NotificationClient(apiKey, "https://api.notifynl.nl", proxy); ``` ## Send a message You can use NotifyNL to send emails, text messages and letters. ### Bulk sending You cannot use a single API call to send messages in bulk. To send a batch of messages, use the API to loop over your recipient list, sending one message at a time to each recipient. Make sure you do not exceed our rate limits. ### Send a text message **Method** ```java SendSmsResponse response = client.sendSms( templateId, phoneNumber, personalisation, reference, smsSenderId ); ``` #### **Arguments** **templateId (required)** To find the template ID: 1. [Sign in to NotifyNL](https://admin.notifynl.nl/sign-in). 2. Go to the **Templates** page and select the relevant template. 3. Select **Copy template ID to clipboard**. For example: ```java String templateId="f33517ff-2a88-4f6e-b855-c550268ce08a"; ``` **phoneNumber (required)** The phone number of the recipient of the text message. This number can be a NL or international number. ```java String phoneNumber="+3112345678"; ``` **personalisation (required)** If a template has placeholder fields for personalised information such as name or reference number, you must provide their values in a map. For example: ```java Map personalisation = new HashMap<>(); personalisation.put("first_name", "Amala"); personalisation.put("application_date", "2018-01-01"); personalisation.put("list", listOfItems); // Will appear as a comma separated list in the message ``` If a template does not have any placeholder fields for personalised information, you must pass in an empty map or `null`. **reference (required)** A unique identifier you create. This reference identifies a single unique notification or a batch of notifications. It must not contain any personal information such as name or postal address. If you do not have a reference, you must pass in an empty string or `null`. ```java String reference='STRING'; ``` **smsSenderId (optional)** A unique identifier of the sender of the text message notification. To find the text message sender: 1. [Sign in to NotifyNL](https://admin.notifynl.nl/sign-in). 2. Go to the **Settings** page. 3. In the **Text Messages** section, select **Manage** on the **Text Message sender** row. You can then either: * copy the sender ID that you want to use and paste it into the method * select **Change** to change the default sender that the service will use, and select **Save** ```java String smsSenderId='8e222534-7f05-4972-86e3-17c5d9f894e2' ``` You can leave out this argument if your service only has one text message sender, or if you want to use the default sender. #### **Response** If the request to the client is successful, the client returns a `SendSmsResponse`: ```java UUID notificationId; Optional reference; UUID templateId; int templateVersion; String templateUri; String body; Optional fromNumber; ``` If you are using the test API key, all your messages come back with a `delivered` status. All messages sent using the team and guest list or live keys appear on your dashboard. #### **Error codes** If the request is not successful, the client returns an error. To learn more about error structure, go to Errors section.
Error messageHow to fix
ValidationError (status code 400)
phone_number Too many digitsProvide a valid recipient phone number.
phone_number Not enough digitsProvide a valid recipient phone number.
phone_number Not a NL mobile numberProvide a valid Dutch recipient phone number.
phone_number Must not contain letters or symbolsProvide a valid recipient phone number.
phone_number Not a valid country prefixProvide a valid recipient phone number.
BadRequestError (status code 400)
sms_sender_id <sms_sender_id> does not exist in database for service idGo to your service Settings and copy a valid sms_sender_id. Check that the API key you are using and the sms_sender_id belong to the same service.
Cannot send to this recipient when service is in trial mode - see https://admin.notifynl.nl/trial-modeYour service cannot send this text message in trial mode. To fix, you need to request for your service to go live.
Cannot send to international mobile numbersSending to international mobile numbers is turned off for your service. You can change this in your service Settings.
### Send an email **Method** ```java SendEmailResponse response = client.sendEmail( templateId, emailAddress, personalisation, reference, emailReplyToId ); ``` **Arguments** **templateId (required)** To find the template ID: 1. [Sign in to NotifyNL](https://admin.notifynl.nl/sign-in). 2. Go to the **Templates** page and select the relevant template. 3. Select **Copy template ID to clipboard**. For example: ```java String templateId="f33517ff-2a88-4f6e-b855-c550268ce08a"; ``` **emailAddress (required)** The email address of the recipient. ```java String emailAddress='sender@something.com'; ``` **personalisation (required)** If a template has placeholder fields for personalised information such as name or application date, you must provide their values in a map. For example: ```java Map personalisation = new HashMap<>(); personalisation.put("first_name", "Amala"); personalisation.put("application_date", "2018-01-01"); // pass in a list and it will appear as bullet points in the message: personalisation.put("list", listOfItems); ``` If a template does not have any placeholder fields for personalised information, you must pass in an empty map or `null`. Find out how to reduce the risk of malicious content injection in placeholders. **reference (required)** A unique identifier you create. This reference identifies a single unique notification or a batch of notifications. It must not contain any personal information such as name or postal address. If you do not have a reference, you must pass in an empty string or `null`. ```java String reference='STRING'; ``` **oneClickUnsubscribeURL (recommended)** If you send subscription emails you must let recipients opt out of receiving them. Read our Using Notify page for more information about [unsubscribe links](https://admin.notifynl.nl/using-notify/unsubscribe-links). The one-click unsubscribe URL will be added to the headers of your email. Email clients will use it to add an unsubscribe button. ```java URI oneClickUnsubscribeURL = 'https://example.com/unsubscribe.html?opaque=123456789' ``` The one-click unsubscribe URL must respond to an empty `POST` request by unsubscribing the user from your emails. You can include query parameters to help you identify the user. Your unsubscribe URL and response must comply with the guidance specified in [Section 3.1 of IETF RFC 8058](https://www.rfcreader.com/#rfc8058_line139). You can leave out this argument if the email being sent is not a subscription email. You must also add an unsubscribe link to the bottom of your email. The unsubscribe link at the bottom of your email should take the email recipient to a webpage where they can confirm that they want to unsubscribe. Find out how to add a link when you create a **New template** or **Edit** an email template. **emailReplyToId (optional)** This is an email address specified by you to receive replies from your users. You must add at least one reply-to email address before your service can go live. To add a reply-to email address: 1. [Sign in to NotifyNL](https://admin.notifynl.nl/sign-in). 2. Go to the **Settings** page. 3. In the **Email** section, select **Manage** on the **Reply-to email addresses** row. 4. Select **Add reply-to address**. 5. Enter the email address you want to use, and select **Add**. ```java String emailReplyToId='8e222534-7f05-4972-86e3-17c5d9f894e2' ``` You can leave out this argument if your service only has one reply-to email address, or you want to use the default email address. **Response** If the request to the client is successful, the client returns a `SendEmailResponse`: ```java UUID notificationId; Optional reference; Optional oneClickUnsubscribeURL; UUID templateId; int templateVersion; String templateUri; String body; String subject; Optional fromEmail; ``` **Reducing the risk of malicious content injection in placeholders** Notify lets you [personalise messages](/using-notifynl/using-notifynl/personalisation.md) using placeholders. You can [format](/using-notifynl/using-notifynl/formatting-emails-and-letters.md) content or add links and urls into placeholders using Markdown. If you pass in information from untrusted sources (such as online forms) into your Notify template using personalisation, this may be used to add malicious content and links to notifications you send via Notify. The malicious content could be: * Markdown syntax intended to be rendered into HTML * a plain text URL which would be rendered into a clickable phishing link An example of how malicious content can be injected into Notify personalisation: **Template in Notify**: ```markdown Hello ((name)) ``` **Personalisation**: ```json {name: "Anne Example, now [click this evil link](https://malicious.link)"} ``` **Email will appear as**: ``` Dear Anne Example, now click this evil link ``` We recommend you sanitise all input from untrusted sources to prevent the injection of malicious content. You can use a backslash to escape [individual characters](https://www.markdownguide.org/basic-syntax/#characters-you-can-escape). The characters of most concern are those that could be used to add a URL link such as `[`, `]`, `(` or `)`. **Error codes** If the request is not successful, the client returns an error. To learn more about error structure, go to Errors section. | Error message | How to fix | | -------------------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **ValidationError (status code 400)** | | | `email_address Not a valid email address` | Provide a valid recipient email address. | | `one_click_unsubscribe_url is not a valid https url` | Provide a valid https url for your unsubscribe link. | | **BadRequestError (status code 400)** | | | `email_reply_to_id does not exist in database for service id ` | Go to your service Settings and copy a valid `email_reply_to_id`. Double check that the API key you are using and the `email_reply_to_id` belong to the same service. | | `Emails cannot be longer than 2000000 bytes. Your message is bytes.` | Shorten your email message. | | `Cannot send to this recipient when service is in trial mode - see https://admin.notifynl.nl/trial-mode` | Your service cannot send this email in [trial mode](/using-notifynl/using-notifynl/trial-mode.md). To fix, you need to request for your service to go live. | ### Send a file by email To send a file by email, add a placeholder to the template then upload a file. The placeholder will contain a secure link to download the file. The links are unique and unguessable. NotifyNL cannot access or decrypt your file. Your file will be available to download for a default period of 26 weeks (6 months). To help protect your files you can also: * ask recipients to confirm their email address before downloading * choose the length of time that a file is available to download #### **Add contact details to the file download page** 1. [Sign in to NotifyNL](https://admin.notifynl.nl/sign-in). 2. Go to the **Settings** page. 3. In the **Email** section, select **Manage** on the **Send files by email** row. 4. Enter the contact details you want to use, and select **Save**. #### **Add a placeholder to the template** 1. [Sign in to NotifyNL](https://admin.notifynl.nl/sign-in). 2. Go to the **Templates** page and select the relevant email template. 3. Select **Edit**. 4. Add a placeholder to the email template using double brackets. For example: "Download your file at: ((link\_to\_file))" Your email should also tell recipients how long the file will be available to download. #### **Upload your file** You can upload the following files types: * CSV (.csv) * image (.jpeg, .jpg, .png) * Microsoft Excel Spreadsheet (.xlsx) * Microsoft Word Document (.doc, .docx) * PDF (.pdf) * text (.json, .odt, .rtf, .txt) Your file must be smaller than 2MB. [Contact the NotifyNL team](https://admin.notifynl.nl/support) if you need to send other file types. 1. Convert the PDF to a `byte[]`. 2. Pass the `byte[]` to the personalisation argument. 3. Call the sendEmail method. For example: ```java ClassLoader classLoader = getClass().getClassLoader(); File file = new File(classLoader.getResource("document_to_upload.pdf").getFile()); byte [] fileContents = FileUtils.readFileToByteArray(file); HashMap personalisation = new HashMap(); personalisation.put("link_to_file", client.prepareUpload(fileContents)); client.sendEmail(templateId, emailAddress, personalisation, reference, emailReplyToId); ``` #### **Set the filename** To do this you will need version 5.0.0-RELEASE of the Java client library, or a more recent version. You should provide a filename when you upload your file. The filename should tell the recipient what the file contains. A memorable filename can help the recipient to find the file again later. The filename must end with a file extension. For example, `.csv` for a CSV file. If you include the wrong file extension, recipients may not be able to open your file. If you do not provide a filename for your file, Notify will: * generate a random filename * try to add the correct file extension If Notify cannot add the correct file extension, recipients may not be able to open your file. ```java ClassLoader classLoader = getClass().getClassLoader(); File file = new File(classLoader.getResource("document_to_upload.pdf").getFile()); byte [] fileContents = FileUtils.readFileToByteArray(file); HashMap personalisation = new HashMap(); personalisation.put("link_to_file", client.prepareUpload(fileContents, "report.csv")); client.sendEmail(templateId, emailAddress, personalisation, reference, emailReplyToId); ``` #### **Ask recipients to confirm their email address before they can download the file** When a recipient clicks the link in the email you’ve sent them, they have to enter their email address. Only someone who knows the recipient’s email address can download the file. This security feature is turned on by default. #### **Turn off email address check (not recommended)** If you do not want to use this feature, you can turn it off on a file-by-file basis. To do this you will need version 3.19.0-RELEASE of the Java client library, or a more recent version. You should not turn this feature off if you send files that contain: * personally identifiable information * commercially sensitive information * information classified as ‘OFFICIAL’ or ‘OFFICIAL-SENSITIVE’ under the [Government Security Classifications](https://www.gov.uk/government/publications/government-security-classifications) policy To let the recipient download the file without confirming their email address, set the `confirmEmailBeforeDownload` flag to `false`. ```java ClassLoader classLoader = getClass().getClassLoader(); File file = new File(classLoader.getResource("document_to_upload.pdf").getFile()); byte [] fileContents = FileUtils.readFileToByteArray(file); HashMap personalisation = new HashMap(); personalisation.put("link_to_file", client.prepareUpload(fileContents, false, false, "52 weeks")); client.sendEmail(templateId, emailAddress, personalisation, reference, emailReplyToId); ``` **Choose the length of time that a file is available to download** Set the number of weeks you want the file to be available using the `retention_period` parameter. To use this feature you will need 3.19.0-RELEASE of the Java client library, or a more recent version. You can choose any value between 1 week and 78 weeks. When deciding this, you should consider: * the need to protect the recipient’s personal information * whether the recipient will need to download the file again later If you do not choose a value, the file will be available for the default period of 26 weeks (6 months). Files sent before 12 April 2023 had a longer default period of 78 weeks (18 months). ```java ClassLoader classLoader = getClass().getClassLoader(); File file = new File(classLoader.getResource("document_to_upload.pdf").getFile()); byte [] fileContents = FileUtils.readFileToByteArray(file); HashMap personalisation = new HashMap(); personalisation.put("link_to_file", client.prepareUpload( fileContents, false, false, new RetentionPeriodDuration(52, ChronoUnit.WEEKS) )); client.sendEmail(templateId, emailAddress, personalisation, reference, emailReplyToId); ``` **Error codes** If the request is not successful, the client returns an error. To learn more about error structure, go to Errors section. | Error message | How to fix | | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------ | ------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **BadRequestError (status code 400)** | | | `Unsupported file type '(FILE TYPE)'. Supported types are: '(ALLOWED TYPES)'` | Wrong file type. You can only upload .csv, .doc, .docx, .jpeg, .jpg, .odt, .pdf, .png, .rtf, .txt or .xlsx files | | `filename cannot be longer than 100 characters` | Choose a shorter filename | | `filename must end with a file extension. For example, filename.csv` | Include the file extension in your filename | | `Unsupported value for retention_period '(PERIOD)'. Supported periods are from 1 to 78 weeks.` | Choose a period between 1 and 78 weeks | | `Unsupported value for confirm_email_before_download: '(VALUE)'. Use a boolean true or false value.` | Use either True or False | | `File did not pass the virus scan` | The file contains a virus | | `Send files by email has not been set up - add contact details for your service at https://admin.notifynl.nl/services/(SERVICE ID)/service-settings/send-files-by-email` | See how to [add contact details to the file download page](https://docs.notifications.service.gov.uk/java.html#add-contact-details-to-the-file-download-page) | | `Can only send a file by email` | Make sure you are using an email template | | **Client error (no status code)** | | | `ValueError('File is larger than 2MB')` | The file is too big. Files must be smaller than 2MB. | ### Send a letter When you add a new service it will start in [trial mode](/using-notifynl/using-notifynl/trial-mode.md). You can only send letters when your service is live. To send Notify a request to go live: 1. [Sign in to NotifyNL](https://admin.notifynl.nl/sign-in). 2. Go to the **Settings** page. 3. In the **Your service is in trial mode** section, select **request to go live**. **Method** ```java SendLetterResponse response = client.sendLetter( templateId, personalisation, reference ); ``` **Arguments** **templateId (required)** To find the template ID: 1. [Sign in to NotifyNL](https://admin.notifynl.nl/sign-in). 2. Go to the **Templates** page and select the relevant template. 3. Select **Copy template ID to clipboard**. For example: ```java String templateId = "f33517ff-2a88-4f6e-b855-c550268ce08a"; ``` **personalisation (required)** The personalisation argument always contains the following parameters for the letter recipient’s address: * `address_line_1` * `address_line_2` * `address_line_3` * `address_line_4` * `address_line_5` * `address_line_6` * `address_line_7` The address must have at least 3 lines. The last line needs to be a real UK postcode or the name of a country outside the UK. Notify checks for international addresses and will automatically charge you the correct postage. The `postcode` personalisation argument has been replaced. If your template still uses `postcode`, Notify will treat it as the last line of the address. Any other placeholder fields included in the letter template also count as required parameters. You must provide their values in a map. For example: ```java Map personalisation = new HashMap<>(); personalisation.put("address_line_1", "The Occupier"); // mandatory address field personalisation.put("address_line_2", "Flat 2"); // mandatory address field personalisation.put("address_line_3", "SW14 6BH"); // mandatory address field, must be a real UK postcode personalisation.put("first_name", "Amala"); // field from template personalisation.put("application_date", "2018-01-01"); // field from template // pass in a list and it will appear as bullet points in the letter: personalisation.put("list", listOfItems); ``` If a template does not have any placeholder fields for personalised information, you must pass in an empty map or `null`. **reference (required)** A unique identifier you create. This reference identifies a single unique notification or a batch of notifications. It must not contain any personal information such as name or postal address. If you do not have a reference, you must pass in an empty string or `null`. ```java String reference='STRING'; ``` **Response** If the request to the client is successful, the client returns a `SendLetterResponse`: ```java UUID notificationId; Optional reference; UUID templateId; int templateVersion; String templateUri; String body; String subject; ``` **Error codes** If the request is not successful, the client returns an error. To learn more about error structure, go to Errors section. | Error message | How to fix | | ---------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | **ValidationError (status code 400)** | | | `personalisation address_line_1 is a required property` | Ensure that your template has a field for the first line of the address, check [personalisation](/using-notifynl/using-notifynl/personalisation.md) for more information. | | `Must be a real NL postcode` | Ensure that the value for the last line of the address is a real NL postcode. | | `Must be a real address` | Provide a real recipient address. We do not accept letters for “no fixed abode” addresses, as those cannot be delivered. | | `Last line of address must be a real NL postcode or another country` | Ensure that the value for the last line of the address is a real NL postcode or the name of a country outside the NL. | | `The last line of a BFPO address must not be a country.` | The last line of a BFPO address must not be a country. | | `Address must be at least 3 lines` | Provide at least 3 lines of address. | | `Address must be no more than 7 lines` | Provide no more than 7 lines of address. | | `Address lines must not start with any of the following characters: @ ( ) = [ ] ” \ / , < >` | Change the start of an address line, so it doesn’t start with one of these characters. This is a requirement from our printing provider. | | `postage invalid. It must be either first, second or economy.` | Specify valid postage option. | | **BadRequestError (status code 400)** | | | `Cannot send letters when service is in trial mode - see https://admin.notifynl.nl/trial-mode` | Your service cannot send this letter in [trial mode](/using-notifynl/using-notifynl/trial-mode.md). | | `Service is not allowed to send letters` | Turn on sending letters in your service Settings on NotifyNL webpage | | `letter_contact_id does not exist in database for service id ` | Go to your service Settings and copy a valid `letter_contact_id`. Check that the API key you are using and the `letter_contact_id` belong to the same service. | | **BadRequestError (status code 403)** | | | `Cannot send letters with a team api key` | Use the correct type of [API key](/misc/api-keys.md). | ### Send a precompiled letter **Method** ```java LetterResponse response = client.sendPrecompiledLetter( reference, precompiledPDFAsFile ); ``` ```java LetterResponse response = client.sendPrecompiledLetterWithInputStream( reference, precompiledPDFAsInputStream ); ``` ```java LetterResponse response = client.sendPrecompiledLetter( reference, precompiledPDFAsFile, postage ); ``` ```java LetterResponse response = client.sendPrecompiledLetterWithInputStream( reference, precompiledPDFAsInputStream, postage ); ``` **Arguments** **reference (required)** A unique identifier you create. This reference identifies a single unique notification or a batch of notifications. It must not contain any personal information such as name or postal address. ```java String reference="STRING"; ``` **precompiledPDFAsFile (required for the sendPrecompiledLetter method)** The precompiled letter must be a PDF file which meets [the NotifyNL letter specification](https://admin.notifynl.nl/using-notify/guidance/letter-specification). This argument adds the precompiled letter PDF file to a Java file object. The method sends this Java file object to NotifyNL. ```java File precompiledPDF = new File(""); ``` **precompiledPDFAsInputStream (required for the sendPrecompiledLetterWithInputStream method)** The precompiled letter must be an InputStream. This argument adds the precompiled letter PDF content to a Java InputStream object. The method sends this InputStream to NotifyNL. ```java InputStream precompiledPDFAsInputStream = new FileInputStream(pdfContent); ``` **postage (optional)** You can choose first class, second class or economy mail postage for your precompiled letter. Set the value to `first` for first class, `second` for second class or `economy` for economy mail. If you do not pass in this argument, the postage will default to second class. **Response** If the request to the client is successful, the client returns a `LetterResponse`: ```java UUID notificationId; String reference; String postage ``` **Error codes** If the request is not successful, the client returns an error. To learn more about error structure, go to Errors section. | Error message | How to fix | | ---------------------------------------------------------------------------------------------- | --------------------------------------------------------------------------------------------------------------- | | **ValidationError (status code 400)** | | | `reference is a required property` | Add a `reference` argument to the method call | | `postage invalid. It must be either first, second or economy.` | Change the value of `postage` argument in the method call to either `"first"`, `"second"` or `"economy"` | | **BadRequestError (status code 400)** | | | `Letter content is not a valid PDF` | PDF file format is required. | | `Cannot send letters when service is in trial mode - see https://admin.notifynl.nl/trial-mode` | Your service cannot send this precompiled letter in [trial mode](/using-notifynl/using-notifynl/trial-mode.md). | | **BadRequestError (status code 403)** | | | `Cannot send letters with a team api key` | Use the correct type of [API key](/misc/api-keys.md). | ## Get message data ### Get the data for one message You can only get the data for messages sent within the retention period. The default retention period is 7 days. **Method** ```java Notification notification = client.getNotificationById(notificationId); ``` **Arguments** **notificationId (required)** The ID of the notification. To find the notification ID, you can either: * check the response to the original notification method call * [sign in to NotifyNL](https://admin.notifynl.nl/sign-in) and go to the **API integration** page **Response** If the request to the client is successful, the client returns a `Notification`: ```java UUID id; Optional reference; Optional emailAddress; Optional phoneNumber; Optional line1; Optional line2; Optional line3; Optional line4; Optional line5; Optional line6; Optional line7; Optional postage; String notificationType; String status; UUID templateId; int templateVersion; String templateUri; String body; Optional subject; ZonedDateTime createdAt; Optional sentAt; Optional completedAt; Optional estimatedDelivery; Optional createdByName; boolean isCostDataReady; double costInPounds; Optional billableSmsFragments; Optional internationalRateMultiplier; Optional smsRate; Optional billableSheetsOfPaper; Optional postageType; ``` **Error codes** If the request is not successful, the client returns an error. To learn more about error structure, go to Errors section. | Error message | How to fix | | ------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------ | | **ValidationError (status code 400)** | | | `id is not a valid UUID` | Check the notification ID. | | **NoResultFound (status code 404)** | | | `No result found` | If it’s outside the retention period, you may no longer get the status of the message. The default retention period is 7 days. | ### Get the data for multiple messages This API call returns one page with data for up to 250 messages. You can get either the most recent messages, or get older messages by specifying a particular notification ID in the `olderThanId` argument. You can only get messages that are within your data retention period. The default data retention period is 7 days. It can be changed in your Service Settings. **Method** ```java NotificationList notification = client.getNotifications( status, notificationType, reference, olderThanId ); ``` To get the most recent messages, you must pass in an empty `olderThanId` argument or `null`. To get older messages, pass the ID of an older notification into the `olderThanId` argument. This returns the next oldest messages from the specified notification ID. **Arguments** You can pass in empty arguments or `null` to ignore these filters. **status (optional)** You can filter by each: * email status * text message status * letter status * precompiled letter status You can leave out this argument to ignore this filter. **notificationType (optional)** You can filter by: * `email` * `sms` * `letter` **reference (optional)** A unique identifier you create if necessary. This reference identifies a single unique notification or a batch of notifications. It must not contain any personal information such as name or postal address. ```java String reference='STRING'; ``` **olderThanId (optional)** Input the ID of a notification into this argument. If you use this argument, the client returns the next 250 received notifications older than the given ID. ```java String olderThanId='8e222534-7f05-4972-86e3-17c5d9f894e2' ``` If you pass in an empty argument or `null`, the client returns the most recent 250 notifications. **Response** If the request to the client is successful, the client returns a `NotificationList`: ```java List notifications; String currentPageLink; Optional nextPageLink; ``` **Error codes** If the request is not successful, the client returns an error. To learn more about error structure, go to Errors section. | Error message | How to fix | | ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------- | | **ValidationError (status code 400)** | | | `status ‘elephant’ is not one of [cancelled, created, sending, sent, delivered, pending, failed, technical-failure, temporary-failure, permanent-failure, pending-virus-check, validation-failed, virus-scan-failed, returned-letter, accepted, received]` | Change the [status argument](https://docs.notifications.service.gov.uk/java.html#status-optional). | | `‘Apple’ is not one of [sms, email, letter]` | Change the [template\_type argument](https://docs.notifications.service.gov.uk/java.html#template-type-optional). | ### Email status descriptions | Status | Description | | ------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `created` | NotifyNL has placed the message in a queue, ready to be sent to the provider. It should only remain in this state for a few seconds. | | `sending` | NotifyNL has sent the message to the provider. The provider will try to deliver the message to the recipient for up to 72 hours. NotifyNL is waiting for delivery information. | | `delivered` | The message was successfully delivered. | | `permanent-failure` | The provider could not deliver the message because the email address was wrong. You should remove these email addresses from your database. | | `temporary-failure` | The provider could not deliver the message. This can happen when the recipient’s inbox is full or their anti-spam filter rejects your email. [Check your content does not look like spam](https://www.gov.uk/service-manual/design/sending-emails-and-text-messages#protect-your-users-from-spam-and-phishing) before you try to send the message again. | | `technical-failure` |

Your message was not sent because there was a problem between Notify and the provider.
You’ll have to try sending your messages again.

| ### Text message status descriptions | Status | Description | | ------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `created` | NotifyNL has placed the message in a queue, ready to be sent to the provider. It should only remain in this state for a few seconds. | | `sending` | NotifyNL has sent the message to the provider. The provider will try to deliver the message to the recipient for up to 72 hours. NotifyNL is waiting for delivery information. | | `pending` |

NotifyNL is waiting for more delivery information.
NotifyNL received a callback from the provider but the recipient’s device has not yet responded. Another callback from the provider determines the final status of the text message.

| | `sent` | The message was sent to an international number. The mobile networks in some countries do not provide any more delivery information. The NotifyNL website displays this status as 'Sent to an international number'. | | `delivered` | The message was successfully delivered. | | `permanent-failure` | The provider could not deliver the message. This can happen if the phone number was wrong or if the network operator rejects the message. If you’re sure that these phone numbers are correct, you should [contact NotifyNL support](https://admin.notifynl.nl/support). If not, you should remove them from your database. You’ll still be charged for text messages that cannot be delivered. | | `temporary-failure` | The provider could not deliver the message. This can happen when the recipient’s phone is off, has no signal, or their text message inbox is full. You can try to send the message again. You’ll still be charged for text messages to phones that are not accepting messages. | | `technical-failure` |

Your message was not sent because there was a problem between Notify and the provider.
You’ll have to try sending your messages again. You will not be charged for text messages that are affected by a technical failure.

| ### Letter status descriptions | Status | Description | | ------------------- | ----------------------------------------------------------------------------------- | | `accepted` | NotifyNL has sent the letter to the provider to be printed. | | `received` | The provider has printed and dispatched the letter. | | `cancelled` | Sending cancelled. The letter will not be printed or dispatched. | | `technical-failure` | NotifyNL had an unexpected error while sending the letter to our printing provider. | | `permanent-failure` | The provider cannot print the letter. Your letter will not be dispatched. | ### Precompiled letter status descriptions | Status | Description | | --------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | | `accepted` | NotifyNL has sent the letter to the provider to be printed. | | `received` | The provider has printed and dispatched the letter. | | `cancelled` | Sending cancelled. The letter will not be printed or dispatched. | | `pending-virus-check` | NotifyNL has not completed a virus scan of the precompiled letter file. | | `virus-scan-failed` | NotifyNL found a potential virus in the precompiled letter file. | | `validation-failed` | Content in the precompiled letter file is outside the printable area. See the [NotifyNL letter specification](https://admin.notifynl.nl/using-notify/guidance/letter-specification) for more information. | | `technical-failure` | NotifyNL had an unexpected error while sending the letter to our printing provider. | | `permanent-failure` | The provider cannot print the letter. Your letter will not be dispatched. | ### Get a PDF for a letter notification **Method** This returns the PDF contents of a letter notification. ```java byte[] pdfFile = client.getPdfForLetter(notificationId) ``` **Arguments** **notificationId (required)** The ID of the notification. To find the notification ID, you can either: * check the response to the original notification method call * [sign in to NotifyNL](https://admin.notifynl.nl/sign-in) and go to the **API integration** page **Response** If the request to the client is successful, the client will return a `byte[]` object containing the raw PDF data. **Error codes** If the request is not successful, the client returns an error. To learn more about error structure, go to Errors section. | Error message | How to fix | | ---------------------------------------------------- | --------------------------------------------------------------------------- | | **ValidationError (status code 400)** | | | `id is not a valid UUID` | Check the notification ID. | | `Notification is not a letter` | Check that you are looking up the correct notification. | | **PDFNotReadyError (status code 400)** | | | `PDF not available yet, try again later` | Wait for the letter to finish processing. This usually takes a few seconds. | | **BadRequestError (status code 400)** | | | `File did not pass the virus scan` | You cannot retrieve the contents of a letter that contains a virus. | | `PDF not available for letters in technical-failure` | You cannot retrieve the contents of a letter in technical-failure. | | `Notification is not a letter` | Check that you are looking up the correct notification. | | **NoResultFound (status code 404)** | | | `No result found` | Check the notification ID. | ## Get a template ### Get a template by ID **Method** This returns the latest version of the template. ```java Template template = client.getTemplateById(templateId); ``` **Arguments** **templateId (required)** The ID of the template. [Sign in to NotifyNL](https://admin.notifynl.nl/sign-in) and go to the **Templates** page to find it. ``` String templateId='f33517ff-2a88-4f6e-b855-c550268ce08a'; ``` **Response** If the request to the client is successful, the client returns a `Template`: ```java UUID id; String name; String templateType; ZonedDateTime createdAt; Optional updatedAt; String createdBy; int version; String body; Optional subject; Optional> personalisation; Optional letterContactBlock; ``` **Error codes** If the request is not successful, the client returns an error. To learn more about error structure, go to Errors section. | Error message | How to fix | | ----------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------- | | **NoResultFound (status code 404)** | | | `No Result Found` | Check your [template ID](https://docs.notifications.service.gov.uk/java.html#get-a-template-by-id-arguments-template-id-required). | ### Get a template by ID and version **Method** ```java Template template = client.getTemplateVersion(templateId, version); ``` **Arguments** **templateId (required)** The ID of the template. [Sign in to NotifyNL](https://admin.notifynl.nl/sign-in) and go to the **Templates** page to find it. ```java String templateId='f33517ff-2a88-4f6e-b855-c550268ce08a'; ``` **version (required)** The version number of the template. **Response** If the request to the client is successful, the client returns a `Template`: ```java UUID id; String name; String templateType; ZonedDateTime createdAt; Optional updatedAt; String createdBy; int version; String body; Optional subject; Optional> personalisation; Optional letterContactBlock; ``` **Error codes** If the request is not successful, the client returns an error. To learn more about error structure, go to Errors section. | Error message | How to fix | | ----------------------------------- | ---------------------------------------------------------------------------------------------------------------------------------- | | **NoResultFound (status code 404)** | | | `No Result Found` | Check your [template ID](https://docs.notifications.service.gov.uk/java.html#get-a-template-by-id-arguments-template-id-required). | ### Get all templates **Method** This returns the latest version of all templates. ```java TemplateList templates = client.getAllTemplates(templateType); ``` **Arguments** **templateType (optional)** If you do not use `templateType`, the client returns all templates. Otherwise you can filter by: * `email` * `sms` * `letter` **Response** If the request to the client is successful, the client returns a `TemplateList`: ```java List