Add optional language field to email send

README.md

@@ -11,6 +11,7 @@ MailerSend Java SDK
         - [Send an email](#send-an-email)
         - [Add CC, BCC recipients](#add-cc-bcc-recipients)
         - [Send a template-based email](#send-a-template-based-email)
+        - [Send a template-based email in a specific language](#send-a-template-based-email-in-a-specific-language)
         - [Personalization](#personalization)
         - [Send email with attachment](#send-email-with-attachment)
         - [Send email with inline attachment](#send-email-with-inline-attachment)
@@ -306,6 +307,45 @@ public void sendEmail() {
 }
 ```
 
+### Send a template-based email in a specific language
+
+The optional `language` field is a language code that selects a template translation. It is only meaningful when a template id is set and is ignored
+for raw HTML/text sends. Supported values: `de`, `en`, `es`, `fr`, `it`, `lt`, `nl`, `pl`, `pt-BR`.
+
+```java
+import com.mailersend.sdk.emails.Email;
+import com.mailersend.sdk.MailerSend;
+import com.mailersend.sdk.MailerSendResponse;
+import com.mailersend.sdk.exceptions.MailerSendException;
+
+public void sendEmail() {
+
+    Email email = new Email();
+
+    email.setFrom("name", "your email");
+
+    Recipient recipient = new Recipient("name", "your@recipient.com");
+
+    email.addRecipient(recipient);
+
+    email.setTemplateId("Your MailerSend template ID");
+    email.setLanguage("pt-BR");
+
+    MailerSend ms = new MailerSend();
+
+    ms.setToken("Your API token");
+
+    try {
+
+        MailerSendResponse response = ms.emails().send(email);
+        System.out.println(response.messageId);
+    } catch (MailerSendException e) {
+
+        e.printStackTrace();
+    }
+}
+```
+
 ### Personalization
 
 ```java

src/main/java/com/mailersend/sdk/emails/Email.java

@@ -64,6 +64,9 @@ public class Email {
     @SerializedName("template_id")
     public String templateId;
 
+    @SerializedName("language")
+    public String language;
+
     @SerializedName("tags")
     public ArrayList<String> tags = new ArrayList<String>();
 
@@ -384,10 +387,23 @@ public void setPlain(String plain) {
      * @param templateId a {@link java.lang.String} object.
      */
     public void setTemplateId(String templateId) {
-        
+
         this.templateId = templateId;
     }
-
+
+
+    /**
+     * Sets the email's template translation language as a language code
+     * (e.g. "de", "fr", "pt-BR"). Only meaningful when a template id is set;
+     * ignored for raw html/text sends.
+     *
+     * @param language a {@link java.lang.String} object.
+     */
+    public void setLanguage(String language) {
+
+        this.language = language;
+    }
+
 
     /**
      * Adds a personalization for the given recipient

src/test/java/com/mailersend/sdk/tests/EmailConfigurationTest.java

@@ -357,4 +357,38 @@ public void testCamelCaseAddReplyTo() {
         assertEquals("reply name 2", email.replyTo.name);
         assertEquals("reply2@test.com", email.replyTo.email);
     }
+
+
+    /**
+     * Tests that setLanguage stores the language and it serializes as "language" in JSON
+     */
+    @Test
+    public void testLanguageSerialization() {
+
+        Email email = TestHelper.createBasicEmail(true);
+
+        email.setTemplateId("neqvygm021wl0p7w");
+        email.setLanguage("pt-BR");
+
+        assertEquals("pt-BR", email.language);
+
+        String json = email.serializeForSending();
+
+        assertTrue(json.contains("\"language\""));
+        assertTrue(json.contains("pt-BR"));
+    }
+
+
+    /**
+     * Tests that the language field is omitted from the JSON when not set
+     */
+    @Test
+    public void testLanguageOmittedWhenNotSet() {
+
+        Email email = TestHelper.createBasicEmail(true);
+
+        String json = email.serializeForSending();
+
+        assertTrue(!json.contains("\"language\""));
+    }
 }