public String getFileSystemId() {
        return this.fileSystemId;
    }
<p>
Specifies the EFS file system to which the <code>FileSystemPolicy</code> applies.
</p>

@return Specifies the EFS file system to which the <code>FileSystemPolicy</code> applies.
aws-java-sdk-efs/src/main/java/com/amazonaws/services/elasticfilesystem/model/PutFileSystemPolicyResult.java