public DescribeFileSystemsResult withFileSystems(FileSystemDescription... fileSystems) {
        if (this.fileSystems == null) {
            setFileSystems(new com.amazonaws.internal.SdkInternalList<FileSystemDescription>(fileSystems.length));
        }
        for (FileSystemDescription ele : fileSystems) {
            this.fileSystems.add(ele);
        }
        return this;
    }
<p>
An array of file system descriptions.
</p>
<p>
<b>NOTE:</b> This method appends the values to the existing list (if any). Use
{@link #setFileSystems(java.util.Collection)} or {@link #withFileSystems(java.util.Collection)} if you want to
override the existing values.
</p>

@param fileSystems
       An array of file system descriptions.
@return Returns a reference to this object so that method calls can be chained together.
aws-java-sdk-efs/src/main/java/com/amazonaws/services/elasticfilesystem/model/DescribeFileSystemsResult.java