public void setStackId(String stackId) {
        this.stackId = stackId;
    }
<p>
The app stack ID. If you use this parameter, <code>DescribeApps</code> returns a description of the apps in the
specified stack.
</p>

@param stackId
       The app stack ID. If you use this parameter, <code>DescribeApps</code> returns a description of the apps
       in the specified stack.
aws-java-sdk-opsworks/src/main/java/com/amazonaws/services/opsworks/model/DescribeAppsRequest.java