/**
* Notify all listeners that a rollback is about to occur. If a listener throws an exception then
* no further listeners will be notified and a StandardException with shutdown database(?)
* severity will be thrown.
*
* @throws StandardException
*/
public void preRollbackNotify() throws StandardException {
if (listeners.isEmpty()) return;
for (Iterator i = listeners.iterator(); i.hasNext(); ) {
TransactionListener listener = (TransactionListener) i.next();
try {
listener.preRollback();
i.remove();
} catch (StandardException se) {
// TODO: Define behaviour on exception during rollback.
if (se.getSeverity() < ExceptionSeverity.TRANSACTION_SEVERITY) {}
throw se;
}
}
}
/**
* Convert this page to requested type, as defined by input format id.
*
* <p>The current cache entry is a different format id than the requested type, change it. This
* object is instantiated to the wrong subtype of cachedPage, this routine will create an object
* with the correct subtype, and transfer all pertinent information from this to the new correct
* object.
*
* <p>
*
* @return The new object created with the input fid and transfered info.
* @param fid The format id of the new page.
* @param newIdentity The key of the new page.
* @exception StandardException Standard exception policy.
*/
private CachedPage changeInstanceTo(int fid, PageKey newIdentity) throws StandardException {
CachedPage realPage;
try {
realPage = (CachedPage) Monitor.newInstanceFromIdentifier(fid);
} catch (StandardException se) {
if (se.getSeverity() > ExceptionSeverity.STATEMENT_SEVERITY) {
throw se;
} else {
throw StandardException.newException(
SQLState.DATA_UNKNOWN_PAGE_FORMAT_2,
newIdentity,
org.apache.derby.iapi.util.StringUtil.hexDump(pageData));
}
}
realPage.setFactory(dataFactory);
// avoid creating the data buffer if possible, transfer it to the new
// page if this is the first time the page buffer is used, then
// createPage will create the page array with the correct page size
if (this.pageData != null) {
realPage.alreadyReadPage = true;
realPage.usePageBuffer(this.pageData);
}
// RESOLVE (12/15/06) - the following code is commented out, but
// not sure why.
// this page should not be used any more, null out all its content and
// wait for GC to clean it up
// destroyPage();// let this subtype have a chance to get rid of stuff
// this.pageData = null; // this instance no longer own the data array
// this.pageCache = null;
// this.dataFactory = null;
// this.containerCache = null;
return realPage;
}
/**
* Notify all listeners that a commit is about to occur. If a listener throws an exception then no
* further listeners will be notified and a StandardException with rollback severity will be
* thrown.
*
* @throws StandardException
*/
public void preCommitNotify() throws StandardException {
if (listeners.isEmpty()) return;
for (Iterator i = listeners.iterator(); i.hasNext(); ) {
TransactionListener listener = (TransactionListener) i.next();
try {
if (listener.preCommit()) i.remove();
} catch (StandardException se) {
// This catches any exceptions that have Transaction severity
// or less (e.g. Statement exception).
// If we received any lesser
// error then we abort the transaction anyway.
if (se.getSeverity() < ExceptionSeverity.TRANSACTION_SEVERITY) {
throw StandardException.newException(SQLState.XACT_COMMIT_EXCEPTION, se);
}
throw se;
}
}
}
