I have oracle database 11.2, and I am trying to get oracle change notification working. But it does not seem to notify me, I am using ojdbc6.jar. Table is getting registered into notification; which is verified by running
select * from USER_CHANGE_NOTIFICATION_REGS When I execute an update on table from external client, my listener is not getting called. But when I shutdown/start database it does notify.
import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement; import java.util.Properties; import oracle.jdbc.OracleConnection; import oracle.jdbc.OracleDriver; import oracle.jdbc.OracleStatement; import oracle.jdbc.dcn.DatabaseChangeEvent; import oracle.jdbc.dcn.DatabaseChangeListener; import oracle.jdbc.dcn.DatabaseChangeRegistration; public class DBChangeNotification { static final String USERNAME= "scott"; static final String PASSWORD= "tiger"; static String URL; public static void main(String[] argv) { if(argv.length < 1) { System.out.println("Error: You need to provide the URL in the first argument."); System.out.println(" For example: > java -classpath .:ojdbc5.jar DBChangeNotification \"jdbc:oracle:thin: @(DESCRIPTION=(ADDRESS=(PROTOCOL=tcp)(HOST=yourhost.yourdomain.com)(PORT=1521)) CONNECT_DATA=(SERVICE_NAME=yourservicename)))\""); System.exit(1); } URL = argv[0]; DBChangeNotification demo = new DBChangeNotification(); try { demo.run(); } catch(SQLException mainSQLException ) { mainSQLException.printStackTrace(); } } void run() throws SQLException { OracleConnection conn = connect(); // first step: create a registration on the server: Properties prop = new Properties(); // if connected through the VPN, you need to provide the TCP address of the client. // For example: // prop.setProperty(OracleConnection.NTF_LOCAL_HOST,"14.14.13.12"); // Ask the server to send the ROWIDs as part of the DCN events (small performance // cost): prop.setProperty(OracleConnection.DCN_NOTIFY_ROWIDS,"true"); // //Set the DCN_QUERY_CHANGE_NOTIFICATION option for query registration with finer granularity. prop.setProperty(OracleConnection.DCN_QUERY_CHANGE_NOTIFICATION,"true"); // The following operation does a roundtrip to the database to create a new // registration for DCN. It sends the client address (ip address and port) that // the server will use to connect to the client and send the notification // when necessary. Note that for now the registration is empty (we haven't registered // any table). This also opens a new thread in the drivers. This thread will be // dedicated to DCN (accept connection to the server and dispatch the events to // the listeners). DatabaseChangeRegistration dcr = conn.registerDatabaseChangeNotification(prop); try { // add the listenerr: DCNDemoListener list = new DCNDemoListener(this); dcr.addListener(list); // second step: add objects in the registration: Statement stmt = conn.createStatement(); // associate the statement with the registration: ((OracleStatement)stmt).setDatabaseChangeRegistration(dcr); ResultSet rs = stmt.executeQuery("select rowid from dept where 1 = 2"); while (rs.next()) {} String[] tableNames = dcr.getTables(); for(int i=0;i<tableNames.length;i++) System.out.println(tableNames[i]+" is part of the registration."); rs.close(); stmt.close(); } catch(SQLException ex) { // if an exception occurs, we need to close the registration in order // to interrupt the thread otherwise it will be hanging around. if(conn != null) conn.unregisterDatabaseChangeNotification(dcr); throw ex; } finally { try { // Note that we close the connection! conn.close(); } catch(Exception innerex){ innerex.printStackTrace(); } } synchronized( this ) { // wait until we get the event try{ this.wait();} catch( InterruptedException ie ) {} } // At the end: close the registration (comment out these 3 lines in order // to leave the registration open). OracleConnection conn3 = connect(); conn3.unregisterDatabaseChangeNotification(dcr); conn3.close(); } /** * Creates a connection the database. */ OracleConnection connect() throws SQLException { OracleDriver dr = new OracleDriver(); Properties prop = new Properties(); prop.setProperty("user",DBChangeNotification.USERNAME); prop.setProperty("password",DBChangeNotification.PASSWORD); return (OracleConnection)dr.connect(DBChangeNotification.URL,prop); } } /** * DCN listener: it prints out the event details in stdout. */ class DCNDemoListener implements DatabaseChangeListener { DBChangeNotification demo; DCNDemoListener(DBChangeNotification dem) { demo = dem; } public void onDatabaseChangeNotification(DatabaseChangeEvent e) { Thread t = Thread.currentThread(); System.out.println("DCNDemoListener: got an event ("+this+" running on thread "+t+")"); System.out.println(e.toString()); synchronized( demo ){ demo.notify();} } }