public void setArns(java.util.Collection<String> arns) {
        if (arns == null) {
            this.arns = null;
            return;
        }

        this.arns = new java.util.ArrayList<String>(arns);
    }
<p>
The ARNs of the app blocks.
</p>

@param arns
       The ARNs of the app blocks.
aws-java-sdk-appstream/src/main/java/com/amazonaws/services/appstream/model/DescribeAppBlocksRequest.java