Thanks to Ben and Ross but... Of course the Class.forName connection string has to be invoked first. My brain hurts.
--Bill -----Original Message----- From: u2-users-boun...@listserver.u2ug.org [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Ben Souther Sent: Wednesday, March 24, 2010 1:24 PM To: u2-users@listserver.u2ug.org Subject: Re: [U2] JDBC - Finally - Hitch In Java, variables are local to the block in which they were declared. So, in order to reach your 'con' variable from outside the 'try' block it needs to be declared outside of that block. Connection con = null; // declare con outside of try block. try{ con = DriverManager....... // do stuff with the connection }catch(Exception e){ // handle any exceptions }finally{ try{ con.close(); }catch(Exception ignored){ } } On Wed, 2010-03-24 at 11:49 -0400, Brutzman, Bill wrote: > Ben: > > 1. I am glad to find out about the "finally" command. I was not aware > of this feature in Java. > 2. The new code below yields an IDE error... con cannot be resolved > 3. Connection con was already defined... it gives an error when I do a > con = null; 4. IDE does not accept con.close; 5. While I am happy to > look into this and figure it out... right now I do not know the fix. > > Regards, > > --Bill > > import java.sql.Connection; > import java.sql.DriverManager; > import java.sql.ResultSet; > import java.sql.SQLException; > import java.sql.Statement; > > public class JDBC_1001 { > > public static void main(String[] args) { > try { > > try { > Class.forName("com.ibm.u2.jdbc.UniJDBCDriver"); > } > catch(Exception x){ > System.out.println( "Here " + x ); > } > String url = > "jdbc:ibm-u2://192.168.0.102/SHIPPING"; > String userid > = "ups"; > String passWord = > "brown"; > > Connection con = DriverManager.getConnection(url, userid, > passWord); > > Statement stmt = con.createStatement(); > > String sql = "select @ID, NAME, > CITY, STATE from PACKSLIPS.X"; > ResultSet rs = stmt.executeQuery(sql); > > int i = 1; > while (rs.next() && i < 6) > { > System.out.println("\nRecord "+ i +" :"); > System.out.println("\...@id : \t" + rs.getString(1)); > System.out.println("\tNAME :\t" + rs.getString(2)); > System.out.println("\tCITY :\t" + rs.getString(3)); > System.out.println("\tSTATE :\t" + rs.getString(4)); > i++; > } > > rs.close(); > stmt.close() ; > System.out.println("\n\t*--- QUERY test is done successful > ---*\n"); > > } > catch (SQLException e ) { > System.out.println(e); > } > finally{ > try{ > con.close(); > } > catch(Exception ignored){} > } > } > > } > > -----Original Message----- > From: u2-users-boun...@listserver.u2ug.org > [mailto:u2-users-boun...@listserver.u2ug.org] On Behalf Of Ben Souther > Sent: Tuesday, March 23, 2010 5:34 PM > To: U2 Users List > Subject: Re: [U2] JDBC - ClassPath - Victory > > Glad it's working. > > Tip: You should always put the con.close() statement in a finally > block. > The close method itself can throw an exception so it needs to be in a > nested try/catch. > > Putting in in a finally block insures that come Hello or high water > the connection gets closed. > One of the most common causes for memory leaks in JDBC applications is > the build up of unclosed database connections. > > > Connection con = null; > try{ > // establish connection and do stuff > }catch(Exception e){ > // deal with any problems > }finally{ > try{ > con.close(); > }catch(Exception ignored){} > } > > > > > > > > On Mar 23, 2010, at 3:33 PM, Brutzman, Bill wrote: > > > The following code works ok... > > > > Thanks to all those who responded especially John, Jeff, Bruce, > > Charles, Ben, and Mike. > > > > --Bill > > > > import java.sql.*; > > > > public class Uni_101 { > > > > public static void main(String[] args) { > > try { > > > > try { > > Class.forName("com.ibm.u2.jdbc.UniJDBCDriver"); > > } > > catch(Exception x){ > > System.out.println( "Here " + x ); > > } > > String url = > > "jdbc:ibm-u2://192.168.0.102/SHIPPING"; > > String userid > > = "ups"; > > String passWord = > > "brown"; > > > > Connection con = DriverManager.getConnection(url, userid, > > passWord); > > > > Statement stmt = con.createStatement(); > > > > String sql = "select @ID, NAME, > > CITY, STATE from PACKSLIPS.X"; > > ResultSet rs = stmt.executeQuery(sql); > > > > int i = 1; > > while (rs.next() && i < 6) > > { > > System.out.println("\nRecord "+ i +" :"); > > System.out.println("\...@id : \t" + rs.getString(1)); > > System.out.println("\tNAME :\t" + rs.getString(2)); > > System.out.println("\tCITY :\t" + rs.getString(3)); > > System.out.println("\tSTATE :\t" + rs.getString(4)); > > i++; > > } > > > > rs.close(); > > stmt.close() ; > > System.out.println("\n\t*--- QUERY test is done successful > > ---*\n"); > > > > } > > catch (SQLException e ) { > > System.out.println(e); > > } > > } > > > > } > > _______________________________________________ > > U2-Users mailing list > > U2-Users@listserver.u2ug.org > > http://listserver.u2ug.org/mailman/listinfo/u2-users > > > > _______________________________________________ > U2-Users mailing list > U2-Users@listserver.u2ug.org > http://listserver.u2ug.org/mailman/listinfo/u2-users > _______________________________________________ > U2-Users mailing list > U2-Users@listserver.u2ug.org > http://listserver.u2ug.org/mailman/listinfo/u2-users > -- Ben Souther Manager, Web and Web Service Development bsout...@fwdco.com | 508.927.8147 FWDavison & Company, Inc. 10 Cordage Park Circle, Suite 200 Plymouth, MA 02360-7318 CONFIDENTIALITY NOTICE: This e-mail message, and any accompanying documents, is for the sole use of the intended recipient(s) and may contain confidential and privileged information. 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