public String getSourceIdentity() {
        return this.sourceIdentity;
    }
<p>
The source identity specified by the principal that is calling the <code>AssumeRole</code> operation.
</p>
<p>
You can require users to specify a source identity when they assume a role. You do this by using the
<code>sts:SourceIdentity</code> condition key in a role trust policy. You can use source identity information in
CloudTrail logs to determine who took actions with a role. You can use the <code>aws:SourceIdentity</code>
condition key to further control access to Amazon Web Services resources based on the value of source identity.
For more information about using source identity, see <a
href="https://docs.aws.amazon.com/IAM/latest/UserGuide/id_credentials_temp_control-access_monitor.html">Monitor
and control actions taken with assumed roles</a> in the <i>IAM User Guide</i>.
</p>
<p>
The regex used to validate this parameter is a string of characters consisting of upper- and lower-case
alphanumeric characters with no spaces. You can also include underscores or any of the following characters:
=,.@-. You cannot use a value that begins with the text <code>aws:</code>. This prefix is reserved for Amazon Web
Services internal use.
</p>

@return The source identity specified by the principal that is calling the <code>AssumeRole</code> operation.</p>
        <p>
        You can require users to specify a source identity when they assume a role. You do this by using the
        <code>sts:SourceIdentity</code> condition key in a role trust policy. You can use source identity
        information in CloudTrail logs to determine who took actions with a role. You can use the
        <code>aws:SourceIdentity</code> condition key to further control access to Amazon Web Services resources
        based on the value of source identity. For more information about using source identity, see <a
        href="https://docs.aws.amazon.com/IAM/latest/UserGuide/id_credentials_temp_control-access_monitor.html"
        >Monitor and control actions taken with assumed roles</a> in the <i>IAM User Guide</i>.
        </p>
        <p>
        The regex used to validate this parameter is a string of characters consisting of upper- and lower-case
        alphanumeric characters with no spaces. You can also include underscores or any of the following
        characters: =,.@-. You cannot use a value that begins with the text <code>aws:</code>. This prefix is
        reserved for Amazon Web Services internal use.
aws-java-sdk-sts/src/main/java/com/amazonaws/services/securitytoken/model/AssumeRoleRequest.java