public void setActive(Boolean active) {
        this.active = active;
    }
<p>
When <code>true</code>, StackSets performs non-conflicting operations concurrently and queues conflicting
operations. After conflicting operations finish, StackSets starts queued operations in request order.
</p>
<note>
<p>
If there are already running or queued operations, StackSets queues all incoming operations even if they are
non-conflicting.
</p>
<p>
You can't modify your stack set's execution configuration while there are running or queued operations for that
stack set.
</p>
</note>
<p>
When <code>false</code> (default), StackSets performs one operation at a time in request order.
</p>

@param active
       When <code>true</code>, StackSets performs non-conflicting operations concurrently and queues conflicting
       operations. After conflicting operations finish, StackSets starts queued operations in request order.</p>
       <note>
       <p>
       If there are already running or queued operations, StackSets queues all incoming operations even if they
       are non-conflicting.
       </p>
       <p>
       You can't modify your stack set's execution configuration while there are running or queued operations for
       that stack set.
       </p>
       </note>
       <p>
       When <code>false</code> (default), StackSets performs one operation at a time in request order.
aws-java-sdk-cloudformation/src/main/java/com/amazonaws/services/cloudformation/model/ManagedExecution.java