if can not close the connection to HBase using HTable ...?

[ma qiang]

Hi all,
     If I can not close the connection to HBase using HTable, after
 the object was set as null . Whether the resource of this connection
 will be released ?

     The code as below;

     public class MyMap extends MapReduceBase implements Mapper {
                private HTable connection ;

                public MyMap(){
                       connection=new HTable(new HBaseConfiguration(),
                                        new Text("HBaseTest"));
                }

                public void map(...){
                      ......................
                      connection=null;  // I couldn't use  connection.close;
                }

 }