public void setClientMetadata(java.util.Map<String, String> clientMetadata) {
        this.clientMetadata = clientMetadata;
    }
<p>
A map of custom key-value pairs that you can provide as input for any custom workflows that this action triggers.
</p>
<p>
You create custom workflows by assigning Lambda functions to user pool triggers. When you use the SignUp API
action, Amazon Cognito invokes any functions that are assigned to the following triggers: <i>pre sign-up</i>,
<i>custom message</i>, and <i>post confirmation</i>. When Amazon Cognito invokes any of these functions, it
passes a JSON payload, which the function receives as input. This payload contains a <code>clientMetadata</code>
attribute, which provides the data that you assigned to the ClientMetadata parameter in your SignUp request. In
your function code in Lambda, you can process the <code>clientMetadata</code> value to enhance your workflow for
your specific needs.
</p>
<p>
For more information, see <a href=
"https://docs.aws.amazon.com/cognito/latest/developerguide/cognito-user-identity-pools-working-with-aws-lambda-triggers.html"
> Customizing user pool Workflows with Lambda Triggers</a> in the <i>Amazon Cognito Developer Guide</i>.
</p>
<note>
<p>
When you use the ClientMetadata parameter, remember that Amazon Cognito won't do the following:
</p>
<ul>
<li>
<p>
Store the ClientMetadata value. This data is available only to Lambda triggers that are assigned to a user pool
to support custom workflows. If your user pool configuration doesn't include triggers, the ClientMetadata
parameter serves no purpose.
</p>
</li>
<li>
<p>
Validate the ClientMetadata value.
</p>
</li>
<li>
<p>
Encrypt the ClientMetadata value. Don't use Amazon Cognito to provide sensitive information.
</p>
</li>
</ul>
</note>

@param clientMetadata
       A map of custom key-value pairs that you can provide as input for any custom workflows that this action
       triggers.</p>
       <p>
       You create custom workflows by assigning Lambda functions to user pool triggers. When you use the SignUp
       API action, Amazon Cognito invokes any functions that are assigned to the following triggers: <i>pre
       sign-up</i>, <i>custom message</i>, and <i>post confirmation</i>. When Amazon Cognito invokes any of these
       functions, it passes a JSON payload, which the function receives as input. This payload contains a
       <code>clientMetadata</code> attribute, which provides the data that you assigned to the ClientMetadata
       parameter in your SignUp request. In your function code in Lambda, you can process the
       <code>clientMetadata</code> value to enhance your workflow for your specific needs.
       </p>
       <p>
       For more information, see <a href=
       "https://docs.aws.amazon.com/cognito/latest/developerguide/cognito-user-identity-pools-working-with-aws-lambda-triggers.html"
       > Customizing user pool Workflows with Lambda Triggers</a> in the <i>Amazon Cognito Developer Guide</i>.
       </p>
       <note>
       <p>
       When you use the ClientMetadata parameter, remember that Amazon Cognito won't do the following:
       </p>
       <ul>
       <li>
       <p>
       Store the ClientMetadata value. This data is available only to Lambda triggers that are assigned to a user
       pool to support custom workflows. If your user pool configuration doesn't include triggers, the
       ClientMetadata parameter serves no purpose.
       </p>
       </li>
       <li>
       <p>
       Validate the ClientMetadata value.
       </p>
       </li>
       <li>
       <p>
       Encrypt the ClientMetadata value. Don't use Amazon Cognito to provide sensitive information.
       </p>
       </li>
       </ul>
aws-java-sdk-cognitoidp/src/main/java/com/amazonaws/services/cognitoidp/model/SignUpRequest.java