code: @Deprecated // NOT CURRENTLY INTENDED FOR REMOVAL
      public DB getDB(final String dbName) {
          DB db = dbCache.get(dbName);
          if (db != null) {
              return db;
          }
  
          db = new DB(this, dbName, createOperationExecutor());
          DB temp = dbCache.putIfAbsent(dbName, db);
          if (temp != null) {
              return temp;
          }
          return db;
      }
docs: Gets a database object. Users should use {@link com.mongodb.MongoClient#getDatabase(String)} instead.
  
  <p>
  The {@link DB} class has been superseded by {@link com.mongodb.client.MongoDatabase}.  The deprecation of this method effectively
  deprecates the {@link DB}, {@link DBCollection}, and {@link DBCursor} classes, among others; but in order to give users time to
  migrate to the new API without experiencing a huge number of compiler warnings, those classes have not yet been formally
  deprecated.
  </p>
  
  @param dbName the name of the database to retrieve
  @return a DB representing the specified database
  @throws IllegalArgumentException if the name is invalid
  @see MongoNamespace#checkDatabaseNameValidity(String)
  @deprecated This method is not currently scheduled for removal, but prefer {@link com.mongodb.MongoClient#getDatabase(String)} for
  new code.  Note that {@link DB} and {@link com.mongodb.client.MongoDatabase} can be used together in the same application, whith the
  same {@link MongoClient} instance.