public ReferenceFiles withIndex(FileInformation index) {
        setIndex(index);
        return this;
    }
<p>
The files' index.
</p>

@param index
       The files' index.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-omics/src/main/java/com/amazonaws/services/omics/model/ReferenceFiles.java