empMap.
Map object that stores the identification number and employee name from the source.
lock.
Lock object used to synchronize the access to empMap across partitions.
generateRow.
Boolean variable used to determine if an output row should be generated for the current input row.
isRoot.
Boolean variable used to determine if an employee is at the top of the company organizational chart (root).

// Static Map object to store the ID and name relationship of an 

// employee. If a session uses multiple partitions, empMap is shared

// across all partitions.

private static Map <Integer, String> empMap = new HashMap <Integer, String> (); 

// Static lock object to synchronize the access to empMap across 

// partitions.

private static Object lock = new Object();

// Boolean to track whether to generate an output row based on validity 

// of the input data.

private boolean generateRow;

// Boolean to track whether the employee is root.
private boolean isRoot;