public Message withHeaders(MessageHeader... headers) {
        if (this.headers == null) {
            setHeaders(new java.util.ArrayList<MessageHeader>(headers.length));
        }
        for (MessageHeader ele : headers) {
            this.headers.add(ele);
        }
        return this;
    }
<p>
The list of message headers that will be added to the email message.
</p>
<p>
<b>NOTE:</b> This method appends the values to the existing list (if any). Use
{@link #setHeaders(java.util.Collection)} or {@link #withHeaders(java.util.Collection)} if you want to override
the existing values.
</p>

@param headers
       The list of message headers that will be added to the email message.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-sesv2/src/main/java/com/amazonaws/services/simpleemailv2/model/Message.java