com.ziclix.python.sql

Class PyCursor

java.lang.Object

org.python.core.PyObject

com.ziclix.python.sql.PyCursor

All Implemented Interfaces:

WarningListener, Serializable, ClassDictInit, ContextManager, Traverseproc

Direct Known Subclasses:

PyExtendedCursor

public class PyCursor
extends PyObject
implements ClassDictInit, WarningListener, ContextManager, Traverseproc

These objects represent a database cursor, which is used to manage the context of a fetch operation.

Author:

brian zimmer

See Also:

Serialized Form

Nested Class Summary

Nested classes/interfaces inherited from class org.python.core.PyObject

PyObject.ConversionException

Field Summary

Fields inherited from class org.python.core.PyObject

gcMonitorGlobal, TYPE

Method Summary

Methods

Modifier and Type	Method and Description
void	__del__() Delete the cursor.
PyObject	__enter__()
PyObject	__enter__(ThreadState ts)
boolean	__exit__(PyObject type, PyObject value, PyObject traceback)
boolean	__exit__(ThreadState ts, PyException exception)
PyObject	__findattr_ex__(String name) Gets the value of the attribute name.
PyObject	__iter__() Returns an iteratable object.
PyObject	__iternext__() Return the next element of the sequence that this is an iterator for.
void	__setattr__(String name, PyObject value) Sets the attribute name to value.
void	callproc(PyObject name, PyObject params, PyObject bindings, PyObject maxRows) This method is optional since not all databases provide stored procedures.
static void	classDictInit(PyObject dict) Initializes the object's namespace.
void	close() Close the cursor now (rather than whenever __del__ is called).
void	execute(PyObject sql, PyObject params, PyObject bindings, PyObject maxRows) Prepare and execute a database operation (query or command).
void	executemany(PyObject sql, PyObject params, PyObject bindings, PyObject maxRows) Prepare a database operation (query or command) and then execute it against all parameter sequences or mappings found in the sequence seq_of_parameters.
PyObject	fetchall() Fetch all (remaining) rows of a query result, returning them as a sequence of sequences (e.g. a list of tuples).
PyObject	fetchmany(int size) Fetch the next set of rows of a query result, returning a sequence of sequences (e.g. a list of tuples).
PyObject	fetchone() Fetch the next row of a query result set, returning a single sequence, or None when no more data is available.
DataHandler	getDataHandler() Return the currently bound DataHandler.
static boolean	hasParams(PyObject params) Method hasParams
static boolean	isSeq(PyObject object) Method isSeq
static boolean	isSeqSeq(PyObject object) Method isSeqSeq
PyObject	next() Returns the next row from the currently executing SQL statement using the same semantics as .fetchone().
PyObject	nextset() Move the result pointer to the next set if available.
PyStatement	prepare(PyObject sql) Prepare a sql statement for later execution.
boolean	refersDirectlyTo(PyObject ob) Optional operation.
void	scroll(int value, String mode) Scroll the cursor in the result set to a new position according to mode.
String	toString() String representation of the object.
int	traverse(Visitproc visit, Object arg) Traverses all directly contained PyObjects.
void	warning(WarningEvent event) Adds a warning to the tuple and will follow the chain as necessary.

Methods inherited from class org.python.core.PyObject

__abs__, __add__, __and__, __call__, __call__, __call__, __call__, __call__, __call__, __call__, __call__, __call__, __call__, __call__, __call__, __call__, __call__, __call__, __call__, __cmp__, __coerce__, __coerce_ex__, __complex__, __contains__, __delattr__, __delattr__, __delete__, __delitem__, __delitem__, __delslice__, __delslice__, __dir__, __div__, __divmod__, __ensure_finalizer__, __eq__, __findattr__, __findattr__, __finditem__, __finditem__, __finditem__, __float__, __floordiv__, __format__, __ge__, __get__, __getattr__, __getattr__, __getitem__, __getitem__, __getnewargs__, __getslice__, __getslice__, __gt__, __hash__, __hex__, __iadd__, __iand__, __idiv__, __idivmod__, __ifloordiv__, __ilshift__, __imod__, __imul__, __index__, __int__, __invert__, __ior__, __ipow__, __irshift__, __isub__, __itruediv__, __ixor__, __le__, __len__, __long__, __lshift__, __lt__, __mod__, __mul__, __ne__, __neg__, __nonzero__, __not__, __oct__, __or__, __pos__, __pow__, __pow__, __radd__, __rand__, __rdiv__, __rdivmod__, __reduce__, __reduce_ex__, __reduce_ex__, __repr__, __rfloordiv__, __rlshift__, __rmod__, __rmul__, __ror__, __rpow__, __rrshift__, __rshift__, __rsub__, __rtruediv__, __rxor__, __set__, __setattr__, __setitem__, __setitem__, __setitem__, __setslice__, __setslice__, __str__, __sub__, __tojava__, __truediv__, __trunc__, __unicode__, __xor__, _add, _and, _callextra, _cmp, _div, _divmod, _doget, _doget, _doset, _eq, _floordiv, _ge, _gt, _iadd, _iand, _idiv, _idivmod, _ifloordiv, _ilshift, _imod, _imul, _in, _ior, _ipow, _irshift, _is, _isnot, _isub, _itruediv, _ixor, _jcall, _jcallexc, _jthrow, _le, _lshift, _lt, _mod, _mul, _ne, _notin, _or, _pow, _rshift, _sub, _truediv, _xor, asDouble, asIndex, asIndex, asInt, asInt, asIterable, asLong, asLong, asName, asName, asString, asString, asStringOrNull, asStringOrNull, bit_length, conjugate, delDict, delType, dispatch__init__, equals, fastGetClass, fastGetDict, getDict, getType, hashCode, implementsDescrDelete, implementsDescrGet, implementsDescrSet, invoke, invoke, invoke, invoke, invoke, invoke, isCallable, isDataDescr, isIndex, isInteger, isMappingType, isNumberType, isSequenceType, noAttributeError, object___subclasshook__, readonlyAttributeError, setDict, setType

Methods inherited from class java.lang.Object

getClass, notify, notifyAll, wait, wait, wait

Method Detail

toString

public String toString()

String representation of the object.

Overrides:

toString in class PyObject

Returns:

a string representation of the object.

__setattr__

public void __setattr__(String name,
               PyObject value)

Sets the attribute name to value.

Overrides:

__setattr__ in class PyObject

Parameters:

name -

value -

See Also:

PyObject.__setattr__(PyString, PyObject)

__findattr_ex__

public PyObject __findattr_ex__(String name)

Gets the value of the attribute name.

Overrides:

__findattr_ex__ in class PyObject

Parameters:

name -

Returns:

the attribute for the given name

classDictInit

public static void classDictInit(PyObject dict)

Initializes the object's namespace.

Parameters:

dict -

__del__

public void __del__()

Delete the cursor.

close

public void close()

Close the cursor now (rather than whenever __del__ is called). The cursor will be unusable from this point forward; an Error (or subclass) exception will be raised if any operation is attempted with the cursor.

__iter__

public PyObject __iter__()

Returns an iteratable object.

Overrides:

__iter__ in class PyObject

Returns:

PyObject

Since:

Jython 2.2, DB API 2.0+

next

public PyObject next()

Returns the next row from the currently executing SQL statement using the same semantics as .fetchone(). A StopIteration exception is raised when the result set is exhausted for Python versions 2.2 and later.

Returns:

PyObject

Since:

Jython 2.2, DB API 2.0+

__iternext__

public PyObject __iternext__()

Return the next element of the sequence that this is an iterator for. Returns null when the end of the sequence is reached.

Overrides:

__iternext__ in class PyObject

Returns:

PyObject

Since:

Jython 2.2

getDataHandler

public DataHandler getDataHandler()

Return the currently bound DataHandler.

Returns:

DataHandler

callproc

public void callproc(PyObject name,
            PyObject params,
            PyObject bindings,
            PyObject maxRows)

This method is optional since not all databases provide stored procedures. Call a stored database procedure with the given name. The sequence of parameters must contain one entry for each argument that the procedure expects. The result of the call is returned as modified copy of the input sequence. Input parameters are left untouched, output and input/output parameters replaced with possibly new values. The procedure may also provide a result set as output. This must then be made available through the standard fetchXXX() methods.

Parameters:

name -

params -

bindings -

maxRows -

executemany

public void executemany(PyObject sql,
               PyObject params,
               PyObject bindings,
               PyObject maxRows)

Prepare a database operation (query or command) and then execute it against all parameter sequences or mappings found in the sequence seq_of_parameters. Modules are free to implement this method using multiple calls to the execute() method or by using array operations to have the database process the sequence as a whole in one call. The same comments as for execute() also apply accordingly to this method. Return values are not defined.

Parameters:

sql -

params -

bindings -

maxRows -

execute

public void execute(PyObject sql,
           PyObject params,
           PyObject bindings,
           PyObject maxRows)

Prepare and execute a database operation (query or command). Parameters may be provided as sequence or mapping and will be bound to variables in the operation. Variables are specified in a database-specific notation (see the module's paramstyle attribute for details). A reference to the operation will be retained by the cursor. If the same operation object is passed in again, then the cursor can optimize its behavior. This is most effective for algorithms where the same operation is used, but different parameters are bound to it (many times). For maximum efficiency when reusing an operation, it is best to use the setinputsizes() method to specify the parameter types and sizes ahead of time. It is legal for a parameter to not match the predefined information; the implementation should compensate, possibly with a loss of efficiency. The parameters may also be specified as list of tuples to e.g. insert multiple rows in a single operation, but this kind of usage is deprecated: executemany() should be used instead. Return values are not defined.

Parameters:

sql - sql string or prepared statement

params - params for a prepared statement

bindings - dictionary of (param index : SQLType binding)

maxRows - integer value of max rows

fetchone

public PyObject fetchone()

Fetch the next row of a query result set, returning a single sequence, or None when no more data is available. An Error (or subclass) exception is raised if the previous call to executeXXX() did not produce any result set or no call was issued yet.

Returns:

a single sequence from the result set, or None when no more data is available

fetchall

public PyObject fetchall()

Fetch all (remaining) rows of a query result, returning them as a sequence of sequences (e.g. a list of tuples). Note that the cursor's arraysize attribute can affect the performance of this operation. An Error (or subclass) exception is raised if the previous call to executeXXX() did not produce any result set or no call was issued yet.

Returns:

a sequence of sequences from the result set, or an empty sequence when no more data is available

fetchmany

public PyObject fetchmany(int size)

Fetch the next set of rows of a query result, returning a sequence of sequences (e.g. a list of tuples). An empty sequence is returned when no more rows are available. The number of rows to fetch per call is specified by the parameter. If it is not given, the cursor's arraysize determines the number of rows to be fetched. The method should try to fetch as many rows as indicated by the size parameter. If this is not possible due to the specified number of rows not being available, fewer rows may be returned. An Error (or subclass) exception is raised if the previous call to executeXXX() did not produce any result set or no call was issued yet. Note there are performance considerations involved with the size parameter. For optimal performance, it is usually best to use the arraysize attribute. If the size parameter is used, then it is best for it to retain the same value from one fetchmany() call to the next.

Parameters:

size -

Returns:

a sequence of sequences from the result set, or an empty sequence when no more data is available

nextset

public PyObject nextset()

Move the result pointer to the next set if available.

Returns:

true if more sets exist, else None

prepare

public PyStatement prepare(PyObject sql)

Prepare a sql statement for later execution.

Parameters:

sql - The sql string to be prepared.

Returns:

A prepared statement usable with .executeXXX()

scroll

public void scroll(int value,
          String mode)

Scroll the cursor in the result set to a new position according to mode. If mode is 'relative' (default), value is taken as offset to the current position in the result set, if set to 'absolute', value states an absolute target position. An IndexError should be raised in case a scroll operation would leave the result set. In this case, the cursor position is left undefined (ideal would be to not move the cursor at all). Note: This method should use native scrollable cursors, if available, or revert to an emulation for forward-only scrollable cursors. The method may raise NotSupportedErrors to signal that a specific operation is not supported by the database (e.g. backward scrolling).

Parameters:

value -

mode -

warning

public void warning(WarningEvent event)

Adds a warning to the tuple and will follow the chain as necessary.

Specified by:

warning in interface WarningListener

Parameters:

event -

isSeq

public static boolean isSeq(PyObject object)

Method isSeq

Parameters:

object -

Returns:

true for any PyList, PyTuple or java.util.List

hasParams

public static boolean hasParams(PyObject params)

Method hasParams

Parameters:

params -

Returns:

boolean

isSeqSeq

public static boolean isSeqSeq(PyObject object)

Method isSeqSeq

Parameters:

object -

Returns:

true is a sequence of sequences

__enter__

public PyObject __enter__(ThreadState ts)

Specified by:

__enter__ in interface ContextManager

__enter__

public PyObject __enter__()

__exit__

public boolean __exit__(ThreadState ts,
               PyException exception)

Specified by:

__exit__ in interface ContextManager

__exit__

public boolean __exit__(PyObject type,
               PyObject value,
               PyObject traceback)

traverse

public int traverse(Visitproc visit,
           Object arg)

Description copied from interface: Traverseproc

Traverses all directly contained PyObjects. Like in CPython, arg must be passed unmodified to visit as its second parameter. If Visitproc.visit(PyObject, Object) returns nonzero, this return value must be returned immediately by traverse. Visitproc.visit(PyObject, Object) must not be called with a null PyObject-argument.

Specified by:

traverse in interface Traverseproc

refersDirectlyTo

public boolean refersDirectlyTo(PyObject ob)

Description copied from interface: Traverseproc

Optional operation. Should only be implemented if it is more efficient than calling Traverseproc.traverse(Visitproc, Object) with a visitproc that just watches out for ob. Must return false if ob is null.

Specified by:

refersDirectlyTo in interface Traverseproc