com.wiredtiger.db.Cursor Class Reference

A WT_CURSOR handle is the interface to a cursor. More...

Public Member Functions
synchronized void	delete ()
String	getKeyFormat ()
	Retrieve the format string for this cursor's key.
String	getValueFormat ()
	Retrieve the format string for this cursor's value.
Cursor	putKeyByte (byte value) throws WiredTigerPackingException
	Append a byte to the cursor's key. More...
Cursor	putKeyByteArray (byte[] value) throws WiredTigerPackingException
	Append a byte array to the cursor's key. More...
Cursor	putKeyByteArray (byte[] value, int off, int len) throws WiredTigerPackingException
	Append a byte array to the cursor's key. More...
Cursor	putKeyInt (int value) throws WiredTigerPackingException
	Append an integer to the cursor's key. More...
Cursor	putKeyLong (long value) throws WiredTigerPackingException
	Append a long to the cursor's key. More...
Cursor	putKeyShort (short value) throws WiredTigerPackingException
	Append a short integer to the cursor's key. More...
Cursor	putKeyString (String value) throws WiredTigerPackingException
	Append a string to the cursor's key. More...
Cursor	putValueByte (byte value) throws WiredTigerPackingException
	Append a byte to the cursor's value. More...
Cursor	putValueByteArray (byte[] value) throws WiredTigerPackingException
	Append a byte array to the cursor's value. More...
Cursor	putValueByteArray (byte[] value, int off, int len) throws WiredTigerPackingException
	Append a byte array to the cursor's value. More...
Cursor	putValueInt (int value) throws WiredTigerPackingException
	Append an integer to the cursor's value. More...
Cursor	putValueLong (long value) throws WiredTigerPackingException
	Append a long to the cursor's value. More...
Cursor	putValueShort (short value) throws WiredTigerPackingException
	Append a short integer to the cursor's value. More...
Cursor	putValueString (String value) throws WiredTigerPackingException
	Append a string to the cursor's value. More...
byte	getKeyByte () throws WiredTigerPackingException
	Retrieve a byte from the cursor's key. More...
void	getKeyByteArray (byte[] output) throws WiredTigerPackingException
	Retrieve a byte array from the cursor's key. More...
void	getKeyByteArray (byte[] output, int off, int len) throws WiredTigerPackingException
	Retrieve a byte array from the cursor's key. More...
byte[]	getKeyByteArray () throws WiredTigerPackingException
	Retrieve a byte array from the cursor's key. More...
int	getKeyInt () throws WiredTigerPackingException
	Retrieve an integer from the cursor's key. More...
long	getKeyLong () throws WiredTigerPackingException
	Retrieve a long from the cursor's key. More...
short	getKeyShort () throws WiredTigerPackingException
	Retrieve a short integer from the cursor's key. More...
String	getKeyString () throws WiredTigerPackingException
	Retrieve a string from the cursor's key. More...
byte	getValueByte () throws WiredTigerPackingException
	Retrieve a byte from the cursor's value. More...
void	getValueByteArray (byte[] output) throws WiredTigerPackingException
	Retrieve a byte array from the cursor's value. More...
void	getValueByteArray (byte[] output, int off, int len) throws WiredTigerPackingException
	Retrieve a byte array from the cursor's value. More...
byte[]	getValueByteArray () throws WiredTigerPackingException
	Retrieve a byte array from the cursor's value. More...
int	getValueInt () throws WiredTigerPackingException
	Retrieve an integer from the cursor's value. More...
long	getValueLong () throws WiredTigerPackingException
	Retrieve a long from the cursor's value. More...
short	getValueShort () throws WiredTigerPackingException
	Retrieve a short integer from the cursor's value. More...
String	getValueString () throws WiredTigerPackingException
	Retrieve a string from the cursor's value. More...
int	insert () throws WiredTigerException
	Insert the cursor's current key/value into the table. More...
int	update () throws WiredTigerException
	Update the cursor's current key/value into the table. More...
int	remove () throws WiredTigerException
	Remove the cursor's current key/value into the table. More...
int	compare (Cursor other) throws WiredTigerException
	Compare this cursor's position to another Cursor. More...
int	next () throws WiredTigerException
	Retrieve the next item in the table. More...
int	prev () throws WiredTigerException
	Retrieve the previous item in the table. More...
int	search () throws WiredTigerException
	Search for an item in the table. More...
SearchStatus	search_near () throws WiredTigerException
	Search for an item in the table. More...
Session	getSession ()
String	getUri ()
int	reset () throws com.wiredtiger.db.WiredTigerException
	Reset the position of the cursor. More...
int	close () throws com.wiredtiger.db.WiredTigerException
	Close the cursor. More...
int	compare_wrap (Cursor other)

Protected Member Functions
	Cursor (long cPtr, boolean cMemoryOwn)
String	getKey_format ()
String	getValue_format ()
int	next_wrap () throws com.wiredtiger.db.WiredTigerException
int	prev_wrap () throws com.wiredtiger.db.WiredTigerException
byte[]	get_key_wrap ()
byte[]	get_value_wrap ()
int	insert_wrap (byte[] k, byte[] v)
int	remove_wrap (byte[] k)
int	search_wrap (byte[] k)
SearchStatus	search_near_wrap (byte[] k)
int	update_wrap (byte[] k, byte[] v)
int	java_init (Object jcursor)

Static Protected Member Functions
static long	getCPtr (Cursor obj)

Protected Attributes
boolean	swigCMemOwn
String	keyFormat
String	valueFormat
PackOutputStream	keyPacker
PackOutputStream	valuePacker
PackInputStream	keyUnpacker
PackInputStream	valueUnpacker

Detailed Description

A WT_CURSOR handle is the interface to a cursor.

Cursors allow data to be searched, iterated and modified, implementing the CRUD (create, read, update and delete) operations. Cursors are opened in the context of a session. If a transaction is started, cursors operate in the context of the transaction until the transaction is resolved.

Raw data is represented by key/value pairs of WT_ITEM structures, but cursors can also provide access to fields within the key and value if the formats are described in the WT_SESSION::create method.

In the common case, a cursor is used to access records in a table. However, cursors can be used on subsets of tables (such as a single column or a projection of multiple columns), as an interface to statistics, configuration data or application-specific data sources. See WT_SESSION::open_cursor for more information.

Thread safety: A WT_CURSOR handle is not usually shared between threads, see Multithreading for more information.

Member Function Documentation

int com.wiredtiger.db.Cursor.close

(

)

throws com.wiredtiger.db.WiredTigerException

Close the cursor.

This releases the resources associated with the cursor handle. Cursors are closed implicitly by ending the enclosing connection or closing the session in which they were opened.

        ret = cursor->close(cursor);

Parameters

cursor

the cursor handle

Returns

zero on success and a non-zero error code on failure. See Error Returns for details.

int com.wiredtiger.db.Cursor.compare

(

Cursor

other

)

throws WiredTigerException

Compare this cursor's position to another Cursor.

Returns

The result of the comparison.

byte com.wiredtiger.db.Cursor.getKeyByte

(

)

throws WiredTigerPackingException

Retrieve a byte from the cursor's key.

Returns

The requested value.

void com.wiredtiger.db.Cursor.getKeyByteArray

(

byte[]

output

)

throws WiredTigerPackingException

Retrieve a byte array from the cursor's key.

Parameters

output

The byte array where the returned value will be stored. The array should be large enough to store the entire data item, if not a truncated value will be returned.

void com.wiredtiger.db.Cursor.getKeyByteArray	(	byte[]	output,
		int	off,
		int	len
	)		throws WiredTigerPackingException

Retrieve a byte array from the cursor's key.

Parameters

output	The byte array where the returned value will be stored.
off	Offset into the destination buffer to start copying into.
len	The length should be large enough to store the entire data item, if not a truncated value will be returned.

byte [] com.wiredtiger.db.Cursor.getKeyByteArray

(

)

throws WiredTigerPackingException

Retrieve a byte array from the cursor's key.

Returns

The requested value.

int com.wiredtiger.db.Cursor.getKeyInt

(

)

throws WiredTigerPackingException

Retrieve an integer from the cursor's key.

Returns

The requested value.

long com.wiredtiger.db.Cursor.getKeyLong

(

)

throws WiredTigerPackingException

Retrieve a long from the cursor's key.

Returns

The requested value.

short com.wiredtiger.db.Cursor.getKeyShort

(

)

throws WiredTigerPackingException

Retrieve a short integer from the cursor's key.

Returns

The requested value.

String com.wiredtiger.db.Cursor.getKeyString

(

)

throws WiredTigerPackingException

Retrieve a string from the cursor's key.

Returns

The requested value.

byte com.wiredtiger.db.Cursor.getValueByte

(

)

throws WiredTigerPackingException

Retrieve a byte from the cursor's value.

Returns

The requested value.

void com.wiredtiger.db.Cursor.getValueByteArray

(

byte[]

output

)

throws WiredTigerPackingException

Retrieve a byte array from the cursor's value.

Parameters

output

The byte array where the returned value will be stored. The array should be large enough to store the entire data item, if not a truncated value will be returned.

void com.wiredtiger.db.Cursor.getValueByteArray	(	byte[]	output,
		int	off,
		int	len
	)		throws WiredTigerPackingException

Retrieve a byte array from the cursor's value.

Parameters

output	The byte array where the returned value will be stored.
off	Offset into the destination buffer to start copying into.
len	The length should be large enough to store the entire data item, if not a truncated value will be returned.

byte [] com.wiredtiger.db.Cursor.getValueByteArray

(

)

throws WiredTigerPackingException

Retrieve a byte array from the cursor's value.

Returns

The requested value.

int com.wiredtiger.db.Cursor.getValueInt

(

)

throws WiredTigerPackingException

Retrieve an integer from the cursor's value.

Returns

The requested value.

long com.wiredtiger.db.Cursor.getValueLong

(

)

throws WiredTigerPackingException

Retrieve a long from the cursor's value.

Returns

The requested value.

short com.wiredtiger.db.Cursor.getValueShort

(

)

throws WiredTigerPackingException

Retrieve a short integer from the cursor's value.

Returns

The requested value.

String com.wiredtiger.db.Cursor.getValueString

(

)

throws WiredTigerPackingException

Retrieve a string from the cursor's value.

Returns

The requested value.

int com.wiredtiger.db.Cursor.insert

(

)

throws WiredTigerException

Insert the cursor's current key/value into the table.

Returns

The status of the operation.

int com.wiredtiger.db.Cursor.next

(

)

throws WiredTigerException

Retrieve the next item in the table.

Returns

The result of the comparison.

int com.wiredtiger.db.Cursor.prev

(

)

throws WiredTigerException

Retrieve the previous item in the table.

Returns

The result of the comparison.

Cursor com.wiredtiger.db.Cursor.putKeyByte

(

byte

value

)

throws WiredTigerPackingException

Append a byte to the cursor's key.

Parameters

value

The value to append.

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putKeyByteArray

(

byte[]

value

)

throws WiredTigerPackingException

Append a byte array to the cursor's key.

Parameters

value

The value to append.

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putKeyByteArray	(	byte[]	value,
		int	off,
		int	len
	)		throws WiredTigerPackingException

Append a byte array to the cursor's key.

Parameters

value	The value to append.
off	The offset into value at which to start.
len	The length of the byte array.

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putKeyInt

(

int

value

)

throws WiredTigerPackingException

Append an integer to the cursor's key.

Parameters

value

The value to append

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putKeyLong

(

long

value

)

throws WiredTigerPackingException

Append a long to the cursor's key.

Parameters

value

The value to append

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putKeyShort

(

short

value

)

throws WiredTigerPackingException

Append a short integer to the cursor's key.

Parameters

value

The value to append

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putKeyString

(

String

value

)

throws WiredTigerPackingException

Append a string to the cursor's key.

Parameters

value

The value to append

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putValueByte

(

byte

value

)

throws WiredTigerPackingException

Append a byte to the cursor's value.

Parameters

value

The value to append

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putValueByteArray

(

byte[]

value

)

throws WiredTigerPackingException

Append a byte array to the cursor's value.

Parameters

value

The value to append

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putValueByteArray	(	byte[]	value,
		int	off,
		int	len
	)		throws WiredTigerPackingException

Append a byte array to the cursor's value.

Parameters

value	The value to append
off	The offset into value at which to start.
len	The length of the byte array.

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putValueInt

(

int

value

)

throws WiredTigerPackingException

Append an integer to the cursor's value.

Parameters

value

The value to append

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putValueLong

(

long

value

)

throws WiredTigerPackingException

Append a long to the cursor's value.

Parameters

value

The value to append

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putValueShort

(

short

value

)

throws WiredTigerPackingException

Append a short integer to the cursor's value.

Parameters

value

The value to append

Returns

This cursor object, so put calls can be chained.

Cursor com.wiredtiger.db.Cursor.putValueString

(

String

value

)

throws WiredTigerPackingException

Append a string to the cursor's value.

Parameters

value

The value to append

Returns

This cursor object, so put calls can be chained.

int com.wiredtiger.db.Cursor.remove

(

)

throws WiredTigerException

Remove the cursor's current key/value into the table.

Returns

The status of the operation.

int com.wiredtiger.db.Cursor.reset

(

)

throws com.wiredtiger.db.WiredTigerException

Reset the position of the cursor.

Any resources held by the cursor are released, and the cursor's key and position are no longer valid. A subsequent iteration with WT_CURSOR::next will move to the first record, or with WT_CURSOR::prev will move to the last record.

        ret = cursor->reset(cursor);

Parameters

cursor

the cursor handle

Returns

zero on success and a non-zero error code on failure. See Error Returns for details.

int com.wiredtiger.db.Cursor.search

(

)

throws WiredTigerException

Search for an item in the table.

Returns

The result of the comparison.

SearchStatus com.wiredtiger.db.Cursor.search_near

(

)

throws WiredTigerException

Search for an item in the table.

Returns

The result of the comparison.

int com.wiredtiger.db.Cursor.update

(

)

throws WiredTigerException

Update the cursor's current key/value into the table.

Returns

The status of the operation.