public void setMessageSystemAttributes(java.util.Map<String, MessageSystemAttributeValue> messageSystemAttributes) {
        this.messageSystemAttributes = messageSystemAttributes == null ? null : new com.amazonaws.internal.SdkInternalMap<String, MessageSystemAttributeValue>(
                messageSystemAttributes);
    }
<p>
The message system attribute to send. Each message system attribute consists of a <code>Name</code>,
<code>Type</code>, and <code>Value</code>.
</p>
<important>
<ul>
<li>
<p>
Currently, the only supported message system attribute is <code>AWSTraceHeader</code>. Its type must be
<code>String</code> and its value must be a correctly formatted X-Ray trace header string.
</p>
</li>
<li>
<p>
The size of a message system attribute doesn't count towards the total size of a message.
</p>
</li>
</ul>
</important>

@param messageSystemAttributes
       The message system attribute to send. Each message system attribute consists of a <code>Name</code>,
       <code>Type</code>, and <code>Value</code>.</p> <important>
       <ul>
       <li>
       <p>
       Currently, the only supported message system attribute is <code>AWSTraceHeader</code>. Its type must be
       <code>String</code> and its value must be a correctly formatted X-Ray trace header string.
       </p>
       </li>
       <li>
       <p>
       The size of a message system attribute doesn't count towards the total size of a message.
       </p>
       </li>
       </ul>
aws-java-sdk-sqs/src/main/java/com/amazonaws/services/sqs/model/SendMessageRequest.java