public String getDriftStatus() {
        return this.driftStatus;
    }
<p>
Status of the stack instance's actual configuration compared to the expected template and parameter configuration
of the stack set to which it belongs.
</p>
<ul>
<li>
<p>
<code>DRIFTED</code>: The stack differs from the expected template and parameter configuration of the stack set
to which it belongs. A stack instance is considered to have drifted if one or more of the resources in the
associated stack have drifted.
</p>
</li>
<li>
<p>
<code>NOT_CHECKED</code>: CloudFormation hasn't checked if the stack instance differs from its expected stack set
configuration.
</p>
</li>
<li>
<p>
<code>IN_SYNC</code>: The stack instance's actual configuration matches its expected stack set configuration.
</p>
</li>
<li>
<p>
<code>UNKNOWN</code>: This value is reserved for future use.
</p>
</li>
</ul>

@return Status of the stack instance's actual configuration compared to the expected template and parameter
        configuration of the stack set to which it belongs.</p>
        <ul>
        <li>
        <p>
        <code>DRIFTED</code>: The stack differs from the expected template and parameter configuration of the
        stack set to which it belongs. A stack instance is considered to have drifted if one or more of the
        resources in the associated stack have drifted.
        </p>
        </li>
        <li>
        <p>
        <code>NOT_CHECKED</code>: CloudFormation hasn't checked if the stack instance differs from its expected
        stack set configuration.
        </p>
        </li>
        <li>
        <p>
        <code>IN_SYNC</code>: The stack instance's actual configuration matches its expected stack set
        configuration.
        </p>
        </li>
        <li>
        <p>
        <code>UNKNOWN</code>: This value is reserved for future use.
        </p>
        </li>
@see StackDriftStatus
aws-java-sdk-cloudformation/src/main/java/com/amazonaws/services/cloudformation/model/StackInstanceSummary.java