thanks for the reply synchrosing servlet code dont work ? Antony Paul
----- Original Message ----- From: "Peter Guyatt" <[EMAIL PROTECTED]> To: "Tomcat Users List" <[EMAIL PROTECTED]> Sent: Friday, November 21, 2003 5:28 PM Subject: RE: [OT] Synchronising database access > Hi There, > > Use a singleton class to manage the database transactions. > > Then implement a owner mechanism. E.g. > > class DbTxMgr { > > String owner = null; > > public synchronized boolean lockMgr (String threadId) { > if (owner == null) { > owner = threadId; > return true; > } else { > if (owner.equals(threadId)) { > return true > } > return false; > } > } > > public synchronized void releaseMgr (String threadId) { > if (owner != null) { > if (owner.equals(threadId)) { > owner = null; > } > } > } > > public synchronized boolean insert (String statement, String threadId) { > if (owner == null) { > owner = threadId; > } > if (owner.equals(threadId)) { > file://do the transaction > } > } > } > > your code > > class tester { > file://name of your thread > Thread t = new Thread("testerThread") > ... > > if (lockMgr(t.getName())) { > file://do database code > } > lockMgr.releaseLock(t.getName()); > > } > > This way olny the owner of the lock can perform transactions and all other > threads must wait for the lock to be released > > Thanks > > Pete > > > -----Original Message----- > From: Antony Paul [mailto:[EMAIL PROTECTED] > Sent: 21 November 2003 11:51 > To: Tomcat Users List > Subject: [OT] Synchronising database access > > > Hi, > I want to synchronise all database access. There are lots of situations > where first first a select query is performed to get the results and then > insert/update data. I dont want to implement row level locking or optimistic > locking. I just want to synchronise the whole process. Only after a thread > completes the entire process other threads can execute the code. How to do > it. Do I have to synchronise on Connection or on this or implement > SingleThreadModel. I also want to know how much extra time a synchronised > block requires than an unsynchronised block. > > Antony Paul. > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > > --------------------------------------------------------------------- > To unsubscribe, e-mail: [EMAIL PROTECTED] > For additional commands, e-mail: [EMAIL PROTECTED] > > --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]