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Guides

Java

1. Installation

Add the SDK to your project using Maven or Gradle:

2. Send your first email

Initialize the client with your API token:

Code
import co.lettermint.Lettermint;

Lettermint lettermint = new Lettermint("your-api-key");

Send your first email:

Code
SendEmailResponse response = lettermint.email()
    .from("John Doe <john@yourdomain.com>")
    .to("recipient@example.com")
    .subject("Hello from Lettermint!")
    .text("Hello! This is a test email.")
    .send();

System.out.println("Email sent with ID: " + response.getMessageId());

3. Email Features

Basic Email

Send a simple text or HTML email:

Code
lettermint.email()
    .from("John Doe <john@yourdomain.com>")
    .to("recipient@example.com")
    .subject("Your account is ready!")
    .html("<h1>Welcome!</h1><p>Thanks for signing up.</p>")
    .text("Welcome! Thanks for signing up.")
    .send();

Multiple Recipients

Send to multiple recipients using CC and BCC:

Code
lettermint.email()
    .from("John Doe <john@yourdomain.com>")
    .to("user1@example.com", "user2@example.com")
    .cc("manager@yourdomain.com")
    .bcc("archive@yourdomain.com")
    .subject("Monthly Newsletter")
    .html("<h1>This Month's Updates</h1>")
    .send();

Custom Headers and Reply-To

Add custom headers and set reply-to addresses:

Code
import java.util.Map;

lettermint.email()
    .from("support@yourdomain.com")
    .to("customer@example.com")
    .replyTo("help@yourdomain.com")
    .subject("Support Ticket #12345")
    .headers(Map.of(
        "X-Priority", "1",
        "X-Ticket-ID", "12345"
    ))
    .html("<p>Your support ticket has been updated.</p>")
    .send();

Metadata

Add metadata for tracking and webhook payloads:

Code
import java.util.Map;

lettermint.email()
    .from("notifications@yourdomain.com")
    .to("user@example.com")
    .subject("Order Confirmation")
    .metadata(Map.of(
        "order_id", "12345",
        "customer_id", "cust_789",
        "campaign", "order_confirmation"
    ))
    .html("<p>Your order has been confirmed.</p>")
    .send();

Tags

Categorize emails for filtering and analytics:

Code
lettermint.email()
    .from("alerts@yourdomain.com")
    .to("admin@example.com")
    .subject("System Alert")
    .tag("system-alerts")
    .html("<p>Critical system alert detected.</p>")
    .send();

Route Selection

Direct emails to specific routes within your project:

Code
lettermint.email()
    .from("notifications@yourdomain.com")
    .to("user@example.com")
    .subject("Welcome!")
    .route("transactional")
    .html("<p>Welcome to our platform.</p>")
    .send();

File Attachments

Attach files to your emails:

Code
import java.nio.file.Files;
import java.nio.file.Path;
import java.util.Base64;

// Read file content
byte[] fileContent = Files.readAllBytes(Path.of("/path/to/document.pdf"));
String encodedContent = Base64.getEncoder().encodeToString(fileContent);

lettermint.email()
    .from("invoices@yourdomain.com")
    .to("customer@example.com")
    .subject("Your Invoice")
    .html("<p>Please find your invoice attached.</p>")
    .attach("invoice.pdf", encodedContent)
    .send();

4. Response

Code
SendEmailResponse response = lettermint.email()
    .from("John Doe <john@yourdomain.com>")
    .to("recipient@example.com")
    .subject("Test")
    .text("Hello!")
    .send();

System.out.println(response.getMessageId()); // Email ID
System.out.println(response.getStatus());    // Current status

Next Steps