public void setColumns(java.util.Collection<TopicColumn> columns) {
        if (columns == null) {
            this.columns = null;
            return;
        }

        this.columns = new java.util.ArrayList<TopicColumn>(columns);
    }
<p>
The list of column definitions.
</p>

@param columns
       The list of column definitions.
aws-java-sdk-quicksight/src/main/java/com/amazonaws/services/quicksight/model/DatasetMetadata.java