/**
* restore the before image of the page
*
* @exception StandardException Standard Derby Error Policy
* @exception IOException problem reading the complete log record from the input stream
*/
public void restoreMe(
Transaction xact, BasePage undoPage, LogInstant CLRInstant, LimitObjectInput in)
throws StandardException, IOException {
int slot = undoPage.findRecordById(recordId, Page.FIRST_SLOT_NUMBER);
if (SanityManager.DEBUG) {
if (!getPageId().equals(undoPage.getPageId()))
SanityManager.THROWASSERT(
"restoreMe cannot restore to a different page. "
+ "doMe page:"
+ getPageId()
+ " undoPage:"
+ undoPage.getPageId());
if (slot != doMeSlot)
SanityManager.THROWASSERT(
"restoreMe cannot restore to a different slot. "
+ "doMe slot:"
+ doMeSlot
+ " undoMe slot: "
+ slot
+ " recordId:"
+ recordId);
}
undoPage.skipField(in); // skip the after image of the column
undoPage.storeField(CLRInstant, slot, fieldId, in);
undoPage.setAuxObject(null);
}
/**
* Restore field to its old value.
*
* @exception IOException Can be thrown by any of the methods of ObjectInput.
* @exception StandardException Standard Derby policy.
* @see LogicalPageOperation#undoMe
*/
public void undoMe(
Transaction xact,
BasePage undoPage,
int undoRecordId,
LogInstant CLRInstant,
LimitObjectInput in)
throws StandardException, IOException {
int slot = undoPage.findRecordById(undoRecordId, Page.FIRST_SLOT_NUMBER);
if (SanityManager.DEBUG) {
// if the record Id has changed, the page had better changed
// this can only happen during recovery since in run time undo,
// this resetRecordHandle gets called and this object have the new
// page number and recordId
if (undoRecordId != this.recordId)
if (undoPage.getPageNumber() == getPageId().getPageNumber())
SanityManager.THROWASSERT(
"recordId changed from "
+ this.recordId
+ " to "
+ undoRecordId
+ " but page number did not change "
+ undoPage.getPageNumber());
if (slot == -1)
SanityManager.THROWASSERT(
"recordId " + undoRecordId + " not found on page " + undoPage.getPageNumber());
}
undoPage.skipField((java.io.ObjectInput) in); // skip the after image of the column
undoPage.storeField(CLRInstant, slot, fieldId, in);
undoPage.setAuxObject(null);
}
