public void set(E value) {
if (dataObject == null) {
throw new IllegalStateException();
}
if (!coll.hasValues()) {
throw new UnsupportedOperationException();
}
DataCursor cursor = null;
boolean doAutoCommit = coll.beginAutoCommit();
try {
cursor = new DataCursor(coll.view, writeAllowed);
if (moveCursor(dataIndex, cursor)) {
cursor.putCurrent(value);
setSlot(dataIndex, cursor);
coll.closeCursor(cursor);
coll.commitAutoCommit(doAutoCommit);
} else {
throw new IllegalStateException();
}
} catch (Exception e) {
coll.closeCursor(cursor);
throw coll.handleException(e, doAutoCommit);
}
}
public void add(E value) {
/*
* The checkIterAddAllowed method ensures that one of the following two
* conditions holds and throws UnsupportedOperationException otherwise:
* 1- This is a list iterator for a recno-renumber database.
* 2- This is a collection iterator for a duplicates database.
*/
coll.checkIterAddAllowed();
OperationStatus status = OperationStatus.SUCCESS;
DataCursor cursor = null;
boolean doAutoCommit = coll.beginAutoCommit();
try {
if (coll.view.keysRenumbered || !coll.areDuplicatesOrdered()) {
/*
* This is a recno-renumber database or a btree/hash database
* with unordered duplicates.
*/
boolean hasPrev = hasPrevious();
if (!hasPrev && !hasNext()) {
/* The collection is empty. */
if (coll.view.keysRenumbered) {
/* Append to an empty recno-renumber database. */
status = coll.view.append(value, null, null);
} else if (coll.view.dupsAllowed && coll.view.range.isSingleKey()) {
/*
* When inserting a duplicate into a single-key range,
* the main key is fixed, so we can always insert into
* an empty collection.
*/
cursor = new DataCursor(coll.view, writeAllowed);
cursor.useRangeKey();
status = cursor.putNoDupData(null, value, null, true);
coll.closeCursor(cursor);
cursor = null;
} else {
throw new IllegalStateException("Collection is empty, cannot add() duplicate");
}
/*
* Move past the record just inserted (the cursor should be
* closed above to prevent multiple open cursors in certain
* DB core modes).
*/
if (status == OperationStatus.SUCCESS) {
next();
dataIndex = nextIndex - 1;
}
} else {
/*
* The collection is non-empty. If hasPrev is true then
* the element at (nextIndex - 1) is available; otherwise
* the element at nextIndex is available.
*/
cursor = new DataCursor(coll.view, writeAllowed);
int insertIndex = hasPrev ? (nextIndex - 1) : nextIndex;
if (!moveCursor(insertIndex, cursor)) {
throw new IllegalStateException();
}
/*
* For a recno-renumber database or a database with
* unsorted duplicates, insert before the iterator 'next'
* position, or after the 'prev' position. Then adjust
* the slots to account for the inserted record.
*/
status = hasPrev ? cursor.putAfter(value) : cursor.putBefore(value);
if (status == OperationStatus.SUCCESS) {
insertSlot(nextIndex, cursor);
}
}
} else {
/* This is a btree/hash database with ordered duplicates. */
cursor = new DataCursor(coll.view, writeAllowed);
if (coll.view.range.isSingleKey()) {
/*
* When inserting a duplicate into a single-key range,
* the main key is fixed.
*/
cursor.useRangeKey();
} else {
/*
* When inserting into a multi-key range, the main key
* is the last dataIndex accessed by next(), previous()
* or add().
*/
if (dataIndex < 0 || !moveCursor(dataIndex, cursor)) {
throw new IllegalStateException();
}
}
/*
* For a hash/btree with duplicates, insert the duplicate,
* put the new record in slot zero, and set the next index
* to slot one (past the new record).
*/
status = cursor.putNoDupData(null, value, null, true);
if (status == OperationStatus.SUCCESS) {
clearSlots();
setSlot(0, cursor);
dataIndex = 0;
nextIndex = 1;
}
}
if (status == OperationStatus.KEYEXIST) {
throw new IllegalArgumentException("Duplicate value");
} else if (status != OperationStatus.SUCCESS) {
throw new IllegalArgumentException("Could not insert: " + status);
}
/* Prevent subsequent set() or remove() call. */
dataObject = null;
coll.closeCursor(cursor);
coll.commitAutoCommit(doAutoCommit);
} catch (Exception e) {
/* Catch RuntimeExceptions too. */
coll.closeCursor(cursor);
throw coll.handleException(e, doAutoCommit);
}
}
public void remove() {
if (dataObject == null) {
throw new IllegalStateException();
}
DataCursor cursor = null;
boolean doAutoCommit = coll.beginAutoCommit();
try {
cursor = new DataCursor(coll.view, writeAllowed);
if (moveCursor(dataIndex, cursor)) {
cursor.delete();
deleteSlot(dataIndex);
dataObject = null;
/*
* Repopulate the block after removing all records, using the
* cursor position of the deleted record as a starting point.
* First try moving forward, since the user was moving forward.
* (It is possible to delete all records in the block only by
* moving forward, i.e, when nextIndex is greater than
* dataIndex.)
*/
if (nextIndex == 0 && keys[0] == null) {
OperationStatus status;
for (int i = 0; i < keys.length; i += 1) {
status = coll.iterateDuplicates() ? cursor.getNext(false) : cursor.getNextNoDup(false);
if (status == OperationStatus.SUCCESS) {
setSlot(i, cursor);
} else {
break;
}
}
/*
* If no records are found past the cursor position, try
* moving backward. If no records are found before the
* cursor position, leave nextIndex set to keys.length,
* which is the same as the initial iterator state and is
* appropriate for an empty key range.
*/
if (keys[0] == null) {
nextIndex = keys.length;
for (int i = nextIndex - 1; i >= 0; i -= 1) {
status =
coll.iterateDuplicates() ? cursor.getPrev(false) : cursor.getPrevNoDup(false);
if (status == OperationStatus.SUCCESS) {
setSlot(i, cursor);
} else {
break;
}
}
}
}
coll.closeCursor(cursor);
coll.commitAutoCommit(doAutoCommit);
} else {
throw new IllegalStateException();
}
} catch (Exception e) {
coll.closeCursor(cursor);
throw coll.handleException(e, doAutoCommit);
}
}
