java - Proper way to do jdbc calls from GWT? -

i doing rpc's in gwt query database , have memory leak in program , have strong suspicion in way have class set up. currently, have connect database within each method have , close out connection @ end of method. doing way cause memory leak? feel programming way leads more code , highly inefficient can't find many samples go off, can suggest better way work? names, ip's have been changed, , i've posted connect method sample of how other method's written.

public class databaseserviceimpl extends remoteserviceservlet implements databaseservice {  private connection con = null; string database = "ioma"; string host = "localhost"; string password = "foo"; string url = "jdbc:mysql://" + host + "/" + database; string user = "foo";  public string connect() {      string connect = "";     try {         class.forname("com.mysql.jdbc.driver");         con = drivermanager.getconnection(url, user, password);      } catch (sqlexception e) {         (throwable t : e)             system.err.println("error connecting database: " + t);     } catch (classnotfoundexception e) {         e.printstacktrace();     }     connect = "database connection aquired";     return connect;  }  public int getassemblercount() {     connect();     try {         int assemblercount = 0;         string query = "select count(*) assemblers";         preparedstatement ps = con.preparestatement(query);         resultset rs = ps.executequery();         rs.next();         assemblercount = rs.getint(1);         rs.close();         ps.close();         con.close();         return assemblercount;     } catch (sqlexception e) {         (throwable t : e)             system.err.println("database error in getassemblercount " + e);         return 0;     }  }} 

you should close in "finally" block, close happens in event of exception.

see answers this related question on doing properly.

this common source of memory leaks , problem.