jdbc - difference between connection.close() and connection= null -


if explicitly close connection calling close() on connection object, have set connection object null. difference in close() , null on connection object? if close connection ,still connection object maintained in connection pool? e.g.

connection dbconnection=null; preparedstatement preparedstatement = null; resultset rs;   try {            connection dbconnection= drivermanager.getconnection("jdbc:hsqldb:file:test5","sa", "");            ...........            ...........            dbconnection.close();            dbconnection=null;            } catch (exception e) {         logger.error("exception occured while fetching record:item details start method "                 + e.getmessage());     } {          try         {             if (rs!=null)             {                 rs.close();                 rs=null;             }          }         catch(sqlexception e)         {             logger.error(resultsetcloseexception                     + e.getmessage());         }          try {             if (preparedstatement != null) {                 preparedstatement.close();                 preparedstatement=null;             }         } catch (sqlexception e) {             logger.error(statementcloseexception                     + e.getmessage());         }         try {             if (dbconnection != null) {                 dbconnection.close();                 dbconnection=null;             }         } catch (sqlexception e) {             logger.error(connectioncloseexception                     + e.getmessage());         }     }

is above code correct way close connection, prepared statement , resultset?

one closes connection, 1 sets connection reference null.

if don't close connection, can have connection leak. important close connection in block.

the close() operation closes connection--it doesn't anything connection reference. might not able do connection, it's not null. once it's closed can released collection pool, that's different yet again.

conclusion:: *connection.close()* close conection database , release resources. ***con = null*** - reference connection object deleted in case if connection open still open i.e. resources not free.

let me correct if getting wrong.


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