public synchronized Date getTimeOfDeath(final ServerName deadServerName) {
    Long time = deadServers.get(deadServerName);
    return time == null ? null : new Date(time);
  }
Get the time when a server died
@param deadServerName the dead server name
@return the date when the server died
hbase-server/src/main/java/org/apache/hadoop/hbase/master/DeadServer.java