public abstract class CursorImpl extends Object implements Cursor
The Cursor provides a variety of static utility methods to construct
cursors with given characteristics or easily search for specific values.
For even friendlier and more flexible construction, see
CursorBuilder
.
Is not thread-safe.
Modifier and Type | Class and Description |
---|---|
protected class |
CursorImpl.BaseIterator
Base implementation of iterator for this cursor, modifiable.
|
protected class |
CursorImpl.DirHandler
Handles moving the cursor in a given direction.
|
protected static class |
CursorImpl.IdImpl
Identifier for a cursor.
|
protected static class |
CursorImpl.PositionImpl
Value object which maintains the current position of the cursor.
|
protected static class |
CursorImpl.SavepointImpl
Value object which represents a complete save state of the cursor.
|
Cursor.Id, Cursor.Position, Cursor.Savepoint
Modifier and Type | Field and Description |
---|---|
protected ColumnMatcher |
_columnMatcher
ColumnMatcher to be used when matching column values
|
protected CursorImpl.PositionImpl |
_curPos
the current row
|
protected CursorImpl.PositionImpl |
_prevPos
the previous row
|
static boolean |
MOVE_FORWARD
boolean value indicating forward movement
|
static boolean |
MOVE_REVERSE
boolean value indicating reverse movement
|
Modifier | Constructor and Description |
---|---|
protected |
CursorImpl(CursorImpl.IdImpl id,
TableImpl table,
CursorImpl.PositionImpl firstPos,
CursorImpl.PositionImpl lastPos) |
Modifier and Type | Method and Description |
---|---|
void |
afterLast()
Resets this cursor for reverse traversal (sets cursor to after the last
row).
|
void |
beforeFirst()
Resets this cursor for forward traversal (sets cursor to before the first
row).
|
static CursorImpl |
createCursor(TableImpl table)
Creates a normal, un-indexed cursor for the given table.
|
boolean |
currentRowMatches(ColumnImpl columnPattern,
Object valuePattern) |
boolean |
currentRowMatches(Column columnPattern,
Object valuePattern)
Returns
true if the current row matches the given pattern. |
boolean |
currentRowMatches(Map<String,?> rowPattern)
Returns
true if the current row matches the given pattern. |
protected boolean |
currentRowMatchesImpl(ColumnImpl columnPattern,
Object valuePattern,
ColumnMatcher columnMatcher) |
protected boolean |
currentRowMatchesImpl(Map<String,?> rowPattern,
ColumnMatcher columnMatcher) |
void |
deleteCurrentRow()
Delete the current row.
|
protected abstract CursorImpl.PositionImpl |
findAnotherPosition(TableImpl.RowState rowState,
CursorImpl.PositionImpl curPos,
boolean moveForward)
Finds the next non-deleted row after the given row (as defined by this
cursor) and returns the id of the row, where "next" may be backwards if
moveForward is
false . |
protected boolean |
findAnotherRow(ColumnImpl columnPattern,
Object valuePattern,
boolean reset,
boolean moveForward,
ColumnMatcher columnMatcher,
Object searchInfo) |
protected boolean |
findAnotherRow(Map<String,?> rowPattern,
boolean reset,
boolean moveForward,
ColumnMatcher columnMatcher,
Object searchInfo) |
protected boolean |
findAnotherRowImpl(ColumnImpl columnPattern,
Object valuePattern,
boolean moveForward,
ColumnMatcher columnMatcher,
Object searchInfo)
Moves to the next row (as defined by the cursor) where the given column
has the given value.
|
protected boolean |
findAnotherRowImpl(Map<String,?> rowPattern,
boolean moveForward,
ColumnMatcher columnMatcher,
Object searchInfo)
Moves to the next row (as defined by the cursor) where the given columns
have the given values.
|
boolean |
findFirstRow(ColumnImpl columnPattern,
Object valuePattern) |
boolean |
findFirstRow(Column columnPattern,
Object valuePattern)
Moves to the first row (as defined by the cursor) where the given column
has the given value.
|
boolean |
findFirstRow(Map<String,?> rowPattern)
Moves to the first row (as defined by the cursor) where the given columns
have the given values.
|
boolean |
findNextRow(ColumnImpl columnPattern,
Object valuePattern) |
boolean |
findNextRow(Column columnPattern,
Object valuePattern)
Moves to the next row (as defined by the cursor) where the given column
has the given value.
|
boolean |
findNextRow(Map<String,?> rowPattern)
Moves to the next row (as defined by the cursor) where the given columns
have the given values.
|
boolean |
findRow(RowId rowId)
Moves to the row with the given rowId.
|
ColumnMatcher |
getColumnMatcher()
Returns the currently configured ColumnMatcher, always non-
null . |
Row |
getCurrentRow()
Returns the current row in this cursor (Column name -> Column value).
|
Row |
getCurrentRow(Collection<String> columnNames)
Returns the current row in this cursor (Column name -> Column value).
|
Object |
getCurrentRowValue(Column column)
Returns the given column from the current row.
|
Object |
getCurrentRowValue(ColumnImpl column) |
protected ColumnMatcher |
getDefaultColumnMatcher()
Returns the default ColumnMatcher for this Cursor.
|
protected abstract CursorImpl.DirHandler |
getDirHandler(boolean moveForward)
Returns the DirHandler for the given movement direction.
|
ErrorHandler |
getErrorHandler()
Gets the currently configured ErrorHandler (always non-
null ). |
protected CursorImpl.PositionImpl |
getFirstPosition()
Returns the first row id (exclusive) as defined by this cursor.
|
JetFormat |
getFormat() |
CursorImpl.IdImpl |
getId() |
protected CursorImpl.PositionImpl |
getLastPosition()
Returns the last row id (exclusive) as defined by this cursor.
|
Row |
getNextRow()
Moves to the next row in the table and returns it.
|
Row |
getNextRow(Collection<String> columnNames)
Moves to the next row in the table and returns it.
|
PageChannel |
getPageChannel() |
Row |
getPreviousRow()
Moves to the previous row in the table and returns it.
|
Row |
getPreviousRow(Collection<String> columnNames)
Moves to the previous row in the table and returns it.
|
protected abstract CursorImpl.PositionImpl |
getRowPosition(RowIdImpl rowId)
Returns the appropriate position information for the given row (which is
the current row and is valid).
|
TableImpl.RowState |
getRowState() |
CursorImpl.SavepointImpl |
getSavepoint()
Returns the current state of the cursor which can be restored at a future
point in time by a call to
Cursor.restoreSavepoint(com.healthmarketscience.jackcess.Cursor.Savepoint) . |
TableImpl |
getTable() |
boolean |
isAfterLast()
Returns
true if the cursor is currently positioned after the
last row, false otherwise. |
protected boolean |
isAtBeginning(boolean moveForward) |
boolean |
isBeforeFirst()
Returns
true if the cursor is currently positioned before the
first row, false otherwise. |
boolean |
isCurrentRowDeleted()
Returns
true if the row at which the cursor is currently
positioned is deleted, false otherwise (including invalid rows). |
protected boolean |
isCurrentRowValid()
Returns
true of the current row is valid, false otherwise. |
protected boolean |
isUpToDate()
Returns
true if this cursor is up-to-date with respect to the
relevant table and related table objects, false otherwise. |
Iterator<Row> |
iterator()
Calls
Cursor.beforeFirst() on this cursor and returns a modifiable
Iterator which will iterate through all the rows of this table. |
Iterator<Row> |
iterator(IterableBuilder iterBuilder) |
protected boolean |
keepSearching(ColumnMatcher columnMatcher,
Object searchInfo)
Called by findAnotherRowImpl to determine if the search should continue
after finding a row which does not match the current pattern.
|
int |
moveNextRows(int numRows)
Moves forward as many rows as possible up to the given number of rows.
|
int |
movePreviousRows(int numRows)
Moves backward as many rows as possible up to the given number of rows.
|
protected boolean |
moveToAnotherRow(boolean moveForward)
Moves to another row in the given direction as defined by this cursor.
|
boolean |
moveToNextRow()
Moves to the next row as defined by this cursor.
|
boolean |
moveToPreviousRow()
Moves to the previous row as defined by this cursor.
|
IterableBuilder |
newIterable()
Convenience method for constructing a new IterableBuilder for this
cursor.
|
protected Object |
prepareSearchInfo(ColumnImpl columnPattern,
Object valuePattern)
Called before a search commences to allow for search specific data to be
generated (which is cached for re-use by the iterators).
|
protected Object |
prepareSearchInfo(Map<String,?> rowPattern)
Called before a search commences to allow for search specific data to be
generated (which is cached for re-use by the iterators).
|
void |
reset()
Resets this cursor for forward traversal.
|
protected void |
reset(boolean moveForward)
Resets this cursor for traversing the given direction.
|
protected void |
restorePosition(CursorImpl.PositionImpl curPos)
Restores a current position for the cursor (current position becomes
previous position).
|
protected void |
restorePosition(CursorImpl.PositionImpl curPos,
CursorImpl.PositionImpl prevPos)
Restores a current and previous position for the cursor if the given
positions are different from the current positions.
|
protected void |
restorePositionImpl(CursorImpl.PositionImpl curPos,
CursorImpl.PositionImpl prevPos)
Restores a current and previous position for the cursor.
|
void |
restoreSavepoint(Cursor.Savepoint savepoint)
Moves the cursor to a savepoint previously returned from
Cursor.getSavepoint() . |
void |
restoreSavepoint(CursorImpl.SavepointImpl savepoint) |
void |
setColumnMatcher(ColumnMatcher columnMatcher)
Sets a new ColumnMatcher.
|
void |
setCurrentRowValue(ColumnImpl column,
Object value) |
void |
setCurrentRowValue(Column column,
Object value)
Updates a single value in the current row.
|
void |
setErrorHandler(ErrorHandler newErrorHandler)
Sets a new ErrorHandler.
|
String |
toString() |
Object[] |
updateCurrentRow(Object... row)
Update the current row.
|
<M extends Map<String,Object>> |
updateCurrentRowFromMap(M row)
Update the current row.
|
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
forEach, spliterator
public static final boolean MOVE_FORWARD
public static final boolean MOVE_REVERSE
protected CursorImpl.PositionImpl _prevPos
protected CursorImpl.PositionImpl _curPos
protected ColumnMatcher _columnMatcher
protected CursorImpl(CursorImpl.IdImpl id, TableImpl table, CursorImpl.PositionImpl firstPos, CursorImpl.PositionImpl lastPos)
public static CursorImpl createCursor(TableImpl table)
table
- the table over which this cursor will traversepublic TableImpl.RowState getRowState()
public CursorImpl.IdImpl getId()
public JetFormat getFormat()
public PageChannel getPageChannel()
public ErrorHandler getErrorHandler()
Cursor
null
).
This will be used to handle all errors.getErrorHandler
in interface Cursor
public void setErrorHandler(ErrorHandler newErrorHandler)
Cursor
null
, resets to using the
ErrorHandler configured at the Table level.setErrorHandler
in interface Cursor
public ColumnMatcher getColumnMatcher()
Cursor
null
.getColumnMatcher
in interface Cursor
public void setColumnMatcher(ColumnMatcher columnMatcher)
Cursor
null
, resets to using the default
matcher (default depends on Cursor type).setColumnMatcher
in interface Cursor
protected ColumnMatcher getDefaultColumnMatcher()
public CursorImpl.SavepointImpl getSavepoint()
Cursor
Cursor.restoreSavepoint(com.healthmarketscience.jackcess.Cursor.Savepoint)
.
Savepoints may be used across different cursor instances for the same
table, but they must have the same Cursor.Id
.
getSavepoint
in interface Cursor
public void restoreSavepoint(Cursor.Savepoint savepoint) throws IOException
Cursor
Cursor.getSavepoint()
.restoreSavepoint
in interface Cursor
IOException
public void restoreSavepoint(CursorImpl.SavepointImpl savepoint) throws IOException
IOException
protected CursorImpl.PositionImpl getFirstPosition()
protected CursorImpl.PositionImpl getLastPosition()
public void reset()
Cursor
Cursor.beforeFirst()
.public void beforeFirst()
Cursor
beforeFirst
in interface Cursor
public void afterLast()
Cursor
public boolean isBeforeFirst() throws IOException
Cursor
true
if the cursor is currently positioned before the
first row, false
otherwise.isBeforeFirst
in interface Cursor
IOException
public boolean isAfterLast() throws IOException
Cursor
true
if the cursor is currently positioned after the
last row, false
otherwise.isAfterLast
in interface Cursor
IOException
protected boolean isAtBeginning(boolean moveForward) throws IOException
IOException
public boolean isCurrentRowDeleted() throws IOException
Cursor
true
if the row at which the cursor is currently
positioned is deleted, false
otherwise (including invalid rows).isCurrentRowDeleted
in interface Cursor
IOException
protected void reset(boolean moveForward)
public Iterator<Row> iterator()
Cursor
Cursor.beforeFirst()
on this cursor and returns a modifiable
Iterator which will iterate through all the rows of this table. Use of
the Iterator follows the same restrictions as a call to
Cursor.getNextRow()
.
For more flexible iteration see Cursor.newIterable()
.public IterableBuilder newIterable()
Cursor
newIterable
in interface Cursor
public Iterator<Row> iterator(IterableBuilder iterBuilder)
public void deleteCurrentRow() throws IOException
Cursor
deleteCurrentRow
in interface Cursor
IOException
public Object[] updateCurrentRow(Object... row) throws IOException
Cursor
updateCurrentRow
in interface Cursor
IOException
public <M extends Map<String,Object>> M updateCurrentRowFromMap(M row) throws IOException
Cursor
updateCurrentRowFromMap
in interface Cursor
IOException
public Row getNextRow() throws IOException
Cursor
getNextRow
in interface Cursor
null
if no next row is foundIOException
public Row getNextRow(Collection<String> columnNames) throws IOException
Cursor
getNextRow
in interface Cursor
columnNames
- Only column names in this collection will be returnednull
if no next row is foundIOException
public Row getPreviousRow() throws IOException
Cursor
getPreviousRow
in interface Cursor
null
if no previous row is foundIOException
public Row getPreviousRow(Collection<String> columnNames) throws IOException
Cursor
getPreviousRow
in interface Cursor
columnNames
- Only column names in this collection will be returnednull
if no previous row is foundIOException
public boolean moveToNextRow() throws IOException
Cursor
moveToNextRow
in interface Cursor
true
if a valid next row was found, false
otherwiseIOException
public boolean moveToPreviousRow() throws IOException
Cursor
moveToPreviousRow
in interface Cursor
true
if a valid previous row was found, false
otherwiseIOException
protected boolean moveToAnotherRow(boolean moveForward) throws IOException
true
if another valid row was found in the given
direction, false
otherwiseIOException
protected void restorePosition(CursorImpl.PositionImpl curPos) throws IOException
IOException
protected final void restorePosition(CursorImpl.PositionImpl curPos, CursorImpl.PositionImpl prevPos) throws IOException
IOException
protected void restorePositionImpl(CursorImpl.PositionImpl curPos, CursorImpl.PositionImpl prevPos) throws IOException
IOException
public boolean findRow(RowId rowId) throws IOException
Cursor
findRow
in interface Cursor
true
if a valid row was found with the given id,
false
if no row was foundIOException
public boolean findFirstRow(Column columnPattern, Object valuePattern) throws IOException
Cursor
Warning, this method always starts searching from the beginning of the Table (you cannot use it to find successive matches).
findFirstRow
in interface Cursor
columnPattern
- column from the table for this cursor which is being
matched by the valuePatternvaluePattern
- value which is equal to the corresponding value in
the matched rowtrue
if a valid row was found with the given value,
false
if no row was foundIOException
public boolean findFirstRow(ColumnImpl columnPattern, Object valuePattern) throws IOException
IOException
public boolean findNextRow(Column columnPattern, Object valuePattern) throws IOException
Cursor
findNextRow
in interface Cursor
columnPattern
- column from the table for this cursor which is being
matched by the valuePatternvaluePattern
- value which is equal to the corresponding value in
the matched rowtrue
if a valid row was found with the given value,
false
if no row was foundIOException
public boolean findNextRow(ColumnImpl columnPattern, Object valuePattern) throws IOException
IOException
protected boolean findAnotherRow(ColumnImpl columnPattern, Object valuePattern, boolean reset, boolean moveForward, ColumnMatcher columnMatcher, Object searchInfo) throws IOException
IOException
public boolean findFirstRow(Map<String,?> rowPattern) throws IOException
Cursor
Warning, this method always starts searching from the beginning of the Table (you cannot use it to find successive matches).
findFirstRow
in interface Cursor
rowPattern
- column names and values which must be equal to the
corresponding values in the matched rowtrue
if a valid row was found with the given values,
false
if no row was foundIOException
public boolean findNextRow(Map<String,?> rowPattern) throws IOException
Cursor
findNextRow
in interface Cursor
rowPattern
- column names and values which must be equal to the
corresponding values in the matched rowtrue
if a valid row was found with the given values,
false
if no row was foundIOException
protected boolean findAnotherRow(Map<String,?> rowPattern, boolean reset, boolean moveForward, ColumnMatcher columnMatcher, Object searchInfo) throws IOException
IOException
public boolean currentRowMatches(Column columnPattern, Object valuePattern) throws IOException
Cursor
true
if the current row matches the given pattern.currentRowMatches
in interface Cursor
columnPattern
- column from the table for this cursor which is being
matched by the valuePatternvaluePattern
- value which is tested for equality with the
corresponding value in the current rowIOException
public boolean currentRowMatches(ColumnImpl columnPattern, Object valuePattern) throws IOException
IOException
protected boolean currentRowMatchesImpl(ColumnImpl columnPattern, Object valuePattern, ColumnMatcher columnMatcher) throws IOException
IOException
public boolean currentRowMatches(Map<String,?> rowPattern) throws IOException
Cursor
true
if the current row matches the given pattern.currentRowMatches
in interface Cursor
rowPattern
- column names and values which must be equal to the
corresponding values in the current rowIOException
protected boolean currentRowMatchesImpl(Map<String,?> rowPattern, ColumnMatcher columnMatcher) throws IOException
IOException
protected boolean findAnotherRowImpl(ColumnImpl columnPattern, Object valuePattern, boolean moveForward, ColumnMatcher columnMatcher, Object searchInfo) throws IOException
Default implementation scans the table from beginning to end.
columnPattern
- column from the table for this cursor which is being
matched by the valuePatternvaluePattern
- value which is equal to the corresponding value in
the matched rowtrue
if a valid row was found with the given value,
false
if no row was foundIOException
protected boolean findAnotherRowImpl(Map<String,?> rowPattern, boolean moveForward, ColumnMatcher columnMatcher, Object searchInfo) throws IOException
Default implementation scans the table from beginning to end.
rowPattern
- column names and values which must be equal to the
corresponding values in the matched rowtrue
if a valid row was found with the given values,
false
if no row was foundIOException
protected Object prepareSearchInfo(ColumnImpl columnPattern, Object valuePattern)
protected Object prepareSearchInfo(Map<String,?> rowPattern)
protected boolean keepSearching(ColumnMatcher columnMatcher, Object searchInfo) throws IOException
IOException
public int moveNextRows(int numRows) throws IOException
Cursor
moveNextRows
in interface Cursor
IOException
public int movePreviousRows(int numRows) throws IOException
Cursor
movePreviousRows
in interface Cursor
IOException
public Row getCurrentRow() throws IOException
Cursor
getCurrentRow
in interface Cursor
IOException
public Row getCurrentRow(Collection<String> columnNames) throws IOException
Cursor
getCurrentRow
in interface Cursor
columnNames
- Only column names in this collection will be returnedIOException
public Object getCurrentRowValue(Column column) throws IOException
Cursor
getCurrentRowValue
in interface Cursor
IOException
public Object getCurrentRowValue(ColumnImpl column) throws IOException
IOException
public void setCurrentRowValue(Column column, Object value) throws IOException
Cursor
setCurrentRowValue
in interface Cursor
IOException
public void setCurrentRowValue(ColumnImpl column, Object value) throws IOException
IOException
protected boolean isUpToDate()
true
if this cursor is up-to-date with respect to the
relevant table and related table objects, false
otherwise.protected boolean isCurrentRowValid() throws IOException
true
of the current row is valid, false
otherwise.IOException
protected abstract CursorImpl.PositionImpl getRowPosition(RowIdImpl rowId) throws IOException
IOException
protected abstract CursorImpl.PositionImpl findAnotherPosition(TableImpl.RowState rowState, CursorImpl.PositionImpl curPos, boolean moveForward) throws IOException
false
. If there are no more rows, the returned
rowId should equal the value returned by getLastPosition()
if
moving forward and getFirstPosition()
if moving backward.IOException
protected abstract CursorImpl.DirHandler getDirHandler(boolean moveForward)
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