public interface Connection extends Wrapper, AutoCloseable
A connection (session) with a specific database. SQL statements are executed and results are returned within the context of a connection.
A Connection
object's database is able to provide information
describing its tables, its supported SQL grammar, its stored
procedures, the capabilities of this connection, and so on. This
information is obtained with the getMetaData
method.
Note: When configuring a Connection
, JDBC applications
should use the appropriate Connection
method such as
setAutoCommit
or setTransactionIsolation
.
Applications should not invoke SQL commands directly to change the connection's
configuration when there is a JDBC method available. By default a Connection
object is in
auto-commit mode, which means that it automatically commits changes
after executing each statement. If auto-commit mode has been
disabled, the method commit
must be called explicitly in
order to commit changes; otherwise, database changes will not be saved.
A new Connection
object created using the JDBC 2.1 core API
has an initially empty type map associated with it. A user may enter a
custom mapping for a UDT in this type map.
When a UDT is retrieved from a data source with the
method ResultSet.getObject
, the getObject
method
will check the connection's type map to see if there is an entry for that
UDT. If so, the getObject
method will map the UDT to the
class indicated. If there is no entry, the UDT will be mapped using the
standard mapping.
A user may create a new type map, which is a java.util.Map
object, make an entry in it, and pass it to the java.sql
methods that can perform custom mapping. In this case, the method
will use the given type map instead of the one associated with
the connection.
For example, the following code fragment specifies that the SQL
type ATHLETES
will be mapped to the class
Athletes
in the Java programming language.
The code fragment retrieves the type map for the Connection
object con
, inserts the entry into it, and then sets
the type map with the new entry as the connection's type map.
java.util.Map map = con.getTypeMap(); map.put("mySchemaName.ATHLETES", Class.forName("Athletes")); con.setTypeMap(map);
Modifier and Type | Field and Description |
---|---|
static int |
TRANSACTION_NONE
A constant indicating that transactions are not supported.
|
static int |
TRANSACTION_READ_COMMITTED
A constant indicating that
dirty reads are prevented; non-repeatable reads and phantom
reads can occur.
|
static int |
TRANSACTION_READ_UNCOMMITTED
A constant indicating that
dirty reads, non-repeatable reads and phantom reads can occur.
|
static int |
TRANSACTION_REPEATABLE_READ
A constant indicating that
dirty reads and non-repeatable reads are prevented; phantom
reads can occur.
|
static int |
TRANSACTION_SERIALIZABLE
A constant indicating that
dirty reads, non-repeatable reads and phantom reads are prevented.
|
Modifier and Type | Method and Description |
---|---|
void |
abort(Executor executor)
Terminates an open connection.
|
void |
clearWarnings()
Clears all warnings reported for this
Connection object. |
void |
close()
Releases this
Connection object's database and JDBC resources
immediately instead of waiting for them to be automatically released. |
void |
commit()
Makes all changes made since the previous
commit/rollback permanent and releases any database locks
currently held by this
Connection object. |
Array |
createArrayOf(String typeName,
Object[] elements)
Factory method for creating Array objects.
|
Blob |
createBlob()
Constructs an object that implements the
Blob interface. |
Clob |
createClob()
Constructs an object that implements the
Clob interface. |
NClob |
createNClob()
Constructs an object that implements the
NClob interface. |
SQLXML |
createSQLXML()
Constructs an object that implements the
SQLXML interface. |
Statement |
createStatement()
Creates a
Statement object for sending
SQL statements to the database. |
Statement |
createStatement(int resultSetType,
int resultSetConcurrency)
Creates a
Statement object that will generate
ResultSet objects with the given type and concurrency. |
Statement |
createStatement(int resultSetType,
int resultSetConcurrency,
int resultSetHoldability)
Creates a
Statement object that will generate
ResultSet objects with the given type, concurrency,
and holdability. |
Struct |
createStruct(String typeName,
Object[] attributes)
Factory method for creating Struct objects.
|
boolean |
getAutoCommit()
Retrieves the current auto-commit mode for this
Connection
object. |
String |
getCatalog()
Retrieves this
Connection object's current catalog name. |
Properties |
getClientInfo()
Returns a list containing the name and current value of each client info
property supported by the driver.
|
String |
getClientInfo(String name)
Returns the value of the client info property specified by name.
|
int |
getHoldability()
Retrieves the current holdability of
ResultSet objects
created using this Connection object. |
DatabaseMetaData |
getMetaData()
Retrieves a
DatabaseMetaData object that contains
metadata about the database to which this
Connection object represents a connection. |
int |
getNetworkTimeout()
Retrieves the number of milliseconds the driver will
wait for a database request to complete.
|
String |
getSchema()
Retrieves this
Connection object's current schema name. |
int |
getTransactionIsolation()
Retrieves this
Connection object's current
transaction isolation level. |
Map<String,Class<?>> |
getTypeMap()
Retrieves the
Map object associated with this
Connection object. |
SQLWarning |
getWarnings()
Retrieves the first warning reported by calls on this
Connection object. |
boolean |
isClosed()
Retrieves whether this
Connection object has been
closed. |
boolean |
isReadOnly()
Retrieves whether this
Connection
object is in read-only mode. |
boolean |
isValid(int timeout)
Returns true if the connection has not been closed and is still valid.
|
String |
nativeSQL(String sql)
Converts the given SQL statement into the system's native SQL grammar.
|
CallableStatement |
prepareCall(String sql)
Creates a
CallableStatement object for calling
database stored procedures. |
CallableStatement |
prepareCall(String sql,
int resultSetType,
int resultSetConcurrency)
Creates a
CallableStatement object that will generate
ResultSet objects with the given type and concurrency. |
CallableStatement |
prepareCall(String sql,
int resultSetType,
int resultSetConcurrency,
int resultSetHoldability)
Creates a
CallableStatement object that will generate
ResultSet objects with the given type and concurrency. |
PreparedStatement |
prepareStatement(String sql)
Creates a
PreparedStatement object for sending
parameterized SQL statements to the database. |
PreparedStatement |
prepareStatement(String sql,
int autoGeneratedKeys)
Creates a default
PreparedStatement object that has
the capability to retrieve auto-generated keys. |
PreparedStatement |
prepareStatement(String sql,
int[] columnIndexes)
Creates a default
PreparedStatement object capable
of returning the auto-generated keys designated by the given array. |
PreparedStatement |
prepareStatement(String sql,
int resultSetType,
int resultSetConcurrency)
Creates a
PreparedStatement object that will generate
ResultSet objects with the given type and concurrency. |
PreparedStatement |
prepareStatement(String sql,
int resultSetType,
int resultSetConcurrency,
int resultSetHoldability)
Creates a
PreparedStatement object that will generate
ResultSet objects with the given type, concurrency,
and holdability. |
PreparedStatement |
prepareStatement(String sql,
String[] columnNames)
Creates a default
PreparedStatement object capable
of returning the auto-generated keys designated by the given array. |
void |
releaseSavepoint(Savepoint savepoint)
Removes the specified
Savepoint and subsequent Savepoint objects from the current
transaction. |
void |
rollback()
Undoes all changes made in the current transaction
and releases any database locks currently held
by this
Connection object. |
void |
rollback(Savepoint savepoint)
Undoes all changes made after the given
Savepoint object
was set. |
void |
setAutoCommit(boolean autoCommit)
Sets this connection's auto-commit mode to the given state.
|
void |
setCatalog(String catalog)
Sets the given catalog name in order to select
a subspace of this
Connection object's database
in which to work. |
void |
setClientInfo(Properties properties)
Sets the value of the connection's client info properties.
|
void |
setClientInfo(String name,
String value)
Sets the value of the client info property specified by name to the
value specified by value.
|
void |
setHoldability(int holdability)
Changes the default holdability of
ResultSet objects
created using this Connection object to the given
holdability. |
void |
setNetworkTimeout(Executor executor,
int milliseconds)
Sets the maximum period a
Connection or
objects created from the Connection
will wait for the database to reply to any one request. |
void |
setReadOnly(boolean readOnly)
Puts this connection in read-only mode as a hint to the driver to enable
database optimizations.
|
Savepoint |
setSavepoint()
Creates an unnamed savepoint in the current transaction and
returns the new
Savepoint object that represents it. |
Savepoint |
setSavepoint(String name)
Creates a savepoint with the given name in the current transaction
and returns the new
Savepoint object that represents it. |
void |
setSchema(String schema)
Sets the given schema name to access.
|
void |
setTransactionIsolation(int level)
Attempts to change the transaction isolation level for this
Connection object to the one given. |
void |
setTypeMap(Map<String,Class<?>> map)
Installs the given
TypeMap object as the type map for
this Connection object. |
isWrapperFor, unwrap
static final int TRANSACTION_NONE
static final int TRANSACTION_READ_UNCOMMITTED
static final int TRANSACTION_READ_COMMITTED
static final int TRANSACTION_REPEATABLE_READ
static final int TRANSACTION_SERIALIZABLE
TRANSACTION_REPEATABLE_READ
and further prohibits the
situation where one transaction reads all rows that satisfy
a WHERE
condition, a second transaction inserts a row that
satisfies that WHERE
condition, and the first transaction
rereads for the same condition, retrieving the additional
"phantom" row in the second read.Statement createStatement() throws SQLException
Statement
object for sending
SQL statements to the database.
SQL statements without parameters are normally
executed using Statement
objects. If the same SQL statement
is executed many times, it may be more efficient to use a
PreparedStatement
object.
Result sets created using the returned Statement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
The holdability of the created result sets can be determined by
calling getHoldability()
.
SQLException
- if a database access error occurs
or this method is called on a closed connectionStatement
objectPreparedStatement prepareStatement(String sql) throws SQLException
PreparedStatement
object for sending
parameterized SQL statements to the database.
A SQL statement with or without IN parameters can be
pre-compiled and stored in a PreparedStatement
object. This
object can then be used to efficiently execute this statement
multiple times.
Note: This method is optimized for handling
parametric SQL statements that benefit from precompilation. If
the driver supports precompilation,
the method prepareStatement
will send
the statement to the database for precompilation. Some drivers
may not support precompilation. In this case, the statement may
not be sent to the database until the PreparedStatement
object is executed. This has no direct effect on users; however, it does
affect which methods throw certain SQLException
objects.
Result sets created using the returned PreparedStatement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
The holdability of the created result sets can be determined by
calling getHoldability()
.
SQLException
- if a database access error occurs
or this method is called on a closed connectionsql
- an SQL statement that may contain one or more '?' IN
parameter placeholdersPreparedStatement
object containing the
pre-compiled SQL statementCallableStatement prepareCall(String sql) throws SQLException
CallableStatement
object for calling
database stored procedures.
The CallableStatement
object provides
methods for setting up its IN and OUT parameters, and
methods for executing the call to a stored procedure.
Note: This method is optimized for handling stored
procedure call statements. Some drivers may send the call
statement to the database when the method prepareCall
is done; others
may wait until the CallableStatement
object
is executed. This has no
direct effect on users; however, it does affect which method
throws certain SQLExceptions.
Result sets created using the returned CallableStatement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
The holdability of the created result sets can be determined by
calling getHoldability()
.
SQLException
- if a database access error occurs
or this method is called on a closed connectionsql
- an SQL statement that may contain one or more '?'
parameter placeholders. Typically this statement is specified using JDBC
call escape syntax.CallableStatement
object containing the
pre-compiled SQL statementString nativeSQL(String sql) throws SQLException
SQLException
- if a database access error occurs
or this method is called on a closed connectionsql
- an SQL statement that may contain one or more '?'
parameter placeholdersvoid setAutoCommit(boolean autoCommit) throws SQLException
commit
or the method rollback
.
By default, new connections are in auto-commit
mode.
The commit occurs when the statement completes. The time when the statement completes depends on the type of SQL Statement:
CallableStatement
objects or for statements that return
multiple results, the statement is complete
when all of the associated result sets have been closed, and all update
counts and output parameters have been retrieved.
NOTE: If this method is called during a transaction and the
auto-commit mode is changed, the transaction is committed. If
setAutoCommit
is called and the auto-commit mode is
not changed, the call is a no-op.
SQLException
- if a database access error occurs,
setAutoCommit(true) is called while participating in a distributed transaction,
or this method is called on a closed connectionautoCommit
- true
to enable auto-commit mode;
false
to disable itgetAutoCommit()
boolean getAutoCommit() throws SQLException
Connection
object.SQLException
- if a database access error occurs
or this method is called on a closed connectionConnection
object's
auto-commit modesetAutoCommit(boolean)
void commit() throws SQLException
Connection
object.
This method should be
used only when auto-commit mode has been disabled.SQLException
- if a database access error occurs,
this method is called while participating in a distributed transaction,
if this method is called on a closed connection or this
Connection
object is in auto-commit modesetAutoCommit(boolean)
void rollback() throws SQLException
Connection
object. This method should be
used only when auto-commit mode has been disabled.SQLException
- if a database access error occurs,
this method is called while participating in a distributed transaction,
this method is called on a closed connection or this
Connection
object is in auto-commit modesetAutoCommit(boolean)
void close() throws SQLException
Connection
object's database and JDBC resources
immediately instead of waiting for them to be automatically released.
Calling the method close
on a Connection
object that is already closed is a no-op.
It is strongly recommended that an application explicitly
commits or rolls back an active transaction prior to calling the
close
method. If the close
method is called
and there is an active transaction, the results are implementation-defined.
close
in interface AutoCloseable
SQLException
- SQLException if a database access error occursboolean isClosed() throws SQLException
Connection
object has been
closed. A connection is closed if the method close
has been called on it or if certain fatal errors have occurred.
This method is guaranteed to return true
only when
it is called after the method Connection.close
has
been called.
This method generally cannot be called to determine whether a connection to a database is valid or invalid. A typical client can determine that a connection is invalid by catching any exceptions that might be thrown when an operation is attempted.
SQLException
- if a database access error occurstrue
if this Connection
object
is closed; false
if it is still openDatabaseMetaData getMetaData() throws SQLException
DatabaseMetaData
object that contains
metadata about the database to which this
Connection
object represents a connection.
The metadata includes information about the database's
tables, its supported SQL grammar, its stored
procedures, the capabilities of this connection, and so on.SQLException
- if a database access error occurs
or this method is called on a closed connectionDatabaseMetaData
object for this
Connection
objectvoid setReadOnly(boolean readOnly) throws SQLException
Note: This method cannot be called during a transaction.
SQLException
- if a database access error occurs, this
method is called on a closed connection or this
method is called during a transactionreadOnly
- true
enables read-only mode;
false
disables itboolean isReadOnly() throws SQLException
Connection
object is in read-only mode.SQLException
- SQLException if a database access error occurs
or this method is called on a closed connectiontrue
if this Connection
object
is read-only; false
otherwisevoid setCatalog(String catalog) throws SQLException
Connection
object's database
in which to work.
If the driver does not support catalogs, it will silently ignore this request.
Calling setCatalog
has no effect on previously created or prepared
Statement
objects. It is implementation defined whether a DBMS
prepare operation takes place immediately when the Connection
method prepareStatement
or prepareCall
is invoked.
For maximum portability, setCatalog
should be called before a
Statement
is created or prepared.
SQLException
- if a database access error occurs
or this method is called on a closed connectioncatalog
- the name of a catalog (subspace in this
Connection
object's database) in which to workgetCatalog()
String getCatalog() throws SQLException
Connection
object's current catalog name.SQLException
- if a database access error occurs
or this method is called on a closed connectionnull
if there is nonesetCatalog(java.lang.String)
void setTransactionIsolation(int level) throws SQLException
Connection
object to the one given.
The constants defined in the interface Connection
are the possible transaction isolation levels.
Note: If this method is called during a transaction, the result is implementation-defined.
SQLException
- if a database access error occurs, this
method is called on a closed connection
or the given parameter is not one of the Connection
constantslevel
- one of the following Connection
constants:
Connection.TRANSACTION_READ_UNCOMMITTED
,
Connection.TRANSACTION_READ_COMMITTED
,
Connection.TRANSACTION_REPEATABLE_READ
, or
Connection.TRANSACTION_SERIALIZABLE
.
(Note that Connection.TRANSACTION_NONE
cannot be used
because it specifies that transactions are not supported.)DatabaseMetaData.supportsTransactionIsolationLevel(int)
,
getTransactionIsolation()
int getTransactionIsolation() throws SQLException
Connection
object's current
transaction isolation level.SQLException
- if a database access error occurs
or this method is called on a closed connectionConnection.TRANSACTION_READ_UNCOMMITTED
,
Connection.TRANSACTION_READ_COMMITTED
,
Connection.TRANSACTION_REPEATABLE_READ
,
Connection.TRANSACTION_SERIALIZABLE
, or
Connection.TRANSACTION_NONE
.setTransactionIsolation(int)
SQLWarning getWarnings() throws SQLException
Connection
object. If there is more than one
warning, subsequent warnings will be chained to the first one
and can be retrieved by calling the method
SQLWarning.getNextWarning
on the warning
that was retrieved previously.
This method may not be
called on a closed connection; doing so will cause an
SQLException
to be thrown.
Note: Subsequent warnings will be chained to this SQLWarning.
SQLException
- if a database access error occurs or
this method is called on a closed connectionSQLWarning
object or null
if there are noneSQLWarning
void clearWarnings() throws SQLException
Connection
object.
After a call to this method, the method getWarnings
returns null
until a new warning is
reported for this Connection
object.SQLException
- SQLException if a database access error occurs
or this method is called on a closed connectionStatement createStatement(int resultSetType, int resultSetConcurrency) throws SQLException
Statement
object that will generate
ResultSet
objects with the given type and concurrency.
This method is the same as the createStatement
method
above, but it allows the default result set
type and concurrency to be overridden.
The holdability of the created result sets can be determined by
calling getHoldability()
.SQLException
- if a database access error occurs, this
method is called on a closed connection
or the given parameters are not ResultSet
constants indicating type and concurrencySQLFeatureNotSupportedException
- if the JDBC driver does not support
this method or this method is not supported for the specified result
set type and result set concurrency.resultSetType
- a result set type; one of
ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
, or
ResultSet.TYPE_SCROLL_SENSITIVE
resultSetConcurrency
- a concurrency type; one of
ResultSet.CONCUR_READ_ONLY
or
ResultSet.CONCUR_UPDATABLE
Statement
object that will generate
ResultSet
objects with the given type and
concurrencyPreparedStatement prepareStatement(String sql, int resultSetType, int resultSetConcurrency) throws SQLException
PreparedStatement
object that will generate
ResultSet
objects with the given type and concurrency.
This method is the same as the prepareStatement
method
above, but it allows the default result set
type and concurrency to be overridden.
The holdability of the created result sets can be determined by
calling getHoldability()
.SQLException
- if a database access error occurs, this
method is called on a closed connection
or the given parameters are not ResultSet
constants indicating type and concurrencySQLFeatureNotSupportedException
- if the JDBC driver does not support
this method or this method is not supported for the specified result
set type and result set concurrency.sql
- a String
object that is the SQL statement to
be sent to the database; may contain one or more '?' IN
parametersresultSetType
- a result set type; one of
ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
, or
ResultSet.TYPE_SCROLL_SENSITIVE
resultSetConcurrency
- a concurrency type; one of
ResultSet.CONCUR_READ_ONLY
or
ResultSet.CONCUR_UPDATABLE
ResultSet
objects with the given type and concurrencyCallableStatement prepareCall(String sql, int resultSetType, int resultSetConcurrency) throws SQLException
CallableStatement
object that will generate
ResultSet
objects with the given type and concurrency.
This method is the same as the prepareCall
method
above, but it allows the default result set
type and concurrency to be overridden.
The holdability of the created result sets can be determined by
calling getHoldability()
.SQLException
- if a database access error occurs, this method
is called on a closed connection
or the given parameters are not ResultSet
constants indicating type and concurrencySQLFeatureNotSupportedException
- if the JDBC driver does not support
this method or this method is not supported for the specified result
set type and result set concurrency.sql
- a String
object that is the SQL statement to
be sent to the database; may contain on or more '?' parametersresultSetType
- a result set type; one of
ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
, or
ResultSet.TYPE_SCROLL_SENSITIVE
resultSetConcurrency
- a concurrency type; one of
ResultSet.CONCUR_READ_ONLY
or
ResultSet.CONCUR_UPDATABLE
CallableStatement
object containing the
pre-compiled SQL statement that will produce ResultSet
objects with the given type and concurrencyMap<String,Class<?>> getTypeMap() throws SQLException
Map
object associated with this
Connection
object.
Unless the application has added an entry, the type map returned
will be empty.
You must invoke setTypeMap
after making changes to the
Map
object returned from
getTypeMap
as a JDBC driver may create an internal
copy of the Map
object passed to setTypeMap
:
Map<String,Class<?>> myMap = con.getTypeMap(); myMap.put("mySchemaName.ATHLETES", Athletes.class); con.setTypeMap(myMap);
SQLException
- if a database access error occurs
or this method is called on a closed connectionSQLFeatureNotSupportedException
- if the JDBC driver does not support
this methodjava.util.Map
object associated
with this Connection
objectsetTypeMap(java.util.Map<java.lang.String, java.lang.Class<?>>)
void setTypeMap(Map<String,Class<?>> map) throws SQLException
TypeMap
object as the type map for
this Connection
object. The type map will be used for the
custom mapping of SQL structured types and distinct types.
You must set the the values for the TypeMap
prior to
callng setMap
as a JDBC driver may create an internal copy
of the TypeMap
:
Map myMap<String,Class<?>> = new HashMap<String,Class<?>>(); myMap.put("mySchemaName.ATHLETES", Athletes.class); con.setTypeMap(myMap);
SQLException
- if a database access error occurs, this
method is called on a closed connection or
the given parameter is not a java.util.Map
objectSQLFeatureNotSupportedException
- if the JDBC driver does not support
this methodmap
- the java.util.Map
object to install
as the replacement for this Connection
object's default type mapgetTypeMap()
void setHoldability(int holdability) throws SQLException
ResultSet
objects
created using this Connection
object to the given
holdability. The default holdability of ResultSet
objects
can be be determined by invoking
DatabaseMetaData.getResultSetHoldability()
.SQLException
- if a database access occurs, this method is called
on a closed connection, or the given parameter
is not a ResultSet
constant indicating holdabilitySQLFeatureNotSupportedException
- if the given holdability is not supportedholdability
- a ResultSet
holdability constant; one of
ResultSet.HOLD_CURSORS_OVER_COMMIT
or
ResultSet.CLOSE_CURSORS_AT_COMMIT
getHoldability()
,
DatabaseMetaData.getResultSetHoldability()
,
ResultSet
int getHoldability() throws SQLException
ResultSet
objects
created using this Connection
object.SQLException
- if a database access error occurs
or this method is called on a closed connectionResultSet.HOLD_CURSORS_OVER_COMMIT
or
ResultSet.CLOSE_CURSORS_AT_COMMIT
setHoldability(int)
,
DatabaseMetaData.getResultSetHoldability()
,
ResultSet
Savepoint setSavepoint() throws SQLException
Savepoint
object that represents it.
if setSavepoint is invoked outside of an active transaction, a transaction will be started at this newly created savepoint.
SQLException
- if a database access error occurs,
this method is called while participating in a distributed transaction,
this method is called on a closed connection
or this Connection
object is currently in
auto-commit modeSQLFeatureNotSupportedException
- if the JDBC driver does not support
this methodSavepoint
objectSavepoint
Savepoint setSavepoint(String name) throws SQLException
Savepoint
object that represents it.
if setSavepoint is invoked outside of an active transaction, a transaction will be started at this newly created savepoint.
SQLException
- if a database access error occurs,
this method is called while participating in a distributed transaction,
this method is called on a closed connection
or this Connection
object is currently in
auto-commit modeSQLFeatureNotSupportedException
- if the JDBC driver does not support
this methodname
- a String
containing the name of the savepointSavepoint
objectSavepoint
void rollback(Savepoint savepoint) throws SQLException
Savepoint
object
was set.
This method should be used only when auto-commit has been disabled.
SQLException
- if a database access error occurs,
this method is called while participating in a distributed transaction,
this method is called on a closed connection,
the Savepoint
object is no longer valid,
or this Connection
object is currently in
auto-commit modeSQLFeatureNotSupportedException
- if the JDBC driver does not support
this methodsavepoint
- the Savepoint
object to roll back toSavepoint
,
rollback()
void releaseSavepoint(Savepoint savepoint) throws SQLException
Savepoint
and subsequent Savepoint
objects from the current
transaction. Any reference to the savepoint after it have been removed
will cause an SQLException
to be thrown.SQLException
- if a database access error occurs, this
method is called on a closed connection or
the given Savepoint
object is not a valid
savepoint in the current transactionSQLFeatureNotSupportedException
- if the JDBC driver does not support
this methodsavepoint
- the Savepoint
object to be removedStatement createStatement(int resultSetType, int resultSetConcurrency, int resultSetHoldability) throws SQLException
Statement
object that will generate
ResultSet
objects with the given type, concurrency,
and holdability.
This method is the same as the createStatement
method
above, but it allows the default result set
type, concurrency, and holdability to be overridden.SQLException
- if a database access error occurs, this
method is called on a closed connection
or the given parameters are not ResultSet
constants indicating type, concurrency, and holdabilitySQLFeatureNotSupportedException
- if the JDBC driver does not support
this method or this method is not supported for the specified result
set type, result set holdability and result set concurrency.resultSetType
- one of the following ResultSet
constants:
ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
, or
ResultSet.TYPE_SCROLL_SENSITIVE
resultSetConcurrency
- one of the following ResultSet
constants:
ResultSet.CONCUR_READ_ONLY
or
ResultSet.CONCUR_UPDATABLE
resultSetHoldability
- one of the following ResultSet
constants:
ResultSet.HOLD_CURSORS_OVER_COMMIT
or
ResultSet.CLOSE_CURSORS_AT_COMMIT
Statement
object that will generate
ResultSet
objects with the given type,
concurrency, and holdabilityResultSet
PreparedStatement prepareStatement(String sql, int resultSetType, int resultSetConcurrency, int resultSetHoldability) throws SQLException
PreparedStatement
object that will generate
ResultSet
objects with the given type, concurrency,
and holdability.
This method is the same as the prepareStatement
method
above, but it allows the default result set
type, concurrency, and holdability to be overridden.
SQLException
- if a database access error occurs, this
method is called on a closed connection
or the given parameters are not ResultSet
constants indicating type, concurrency, and holdabilitySQLFeatureNotSupportedException
- if the JDBC driver does not support
this method or this method is not supported for the specified result
set type, result set holdability and result set concurrency.sql
- a String
object that is the SQL statement to
be sent to the database; may contain one or more '?' IN
parametersresultSetType
- one of the following ResultSet
constants:
ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
, or
ResultSet.TYPE_SCROLL_SENSITIVE
resultSetConcurrency
- one of the following ResultSet
constants:
ResultSet.CONCUR_READ_ONLY
or
ResultSet.CONCUR_UPDATABLE
resultSetHoldability
- one of the following ResultSet
constants:
ResultSet.HOLD_CURSORS_OVER_COMMIT
or
ResultSet.CLOSE_CURSORS_AT_COMMIT
PreparedStatement
object, containing the
pre-compiled SQL statement, that will generate
ResultSet
objects with the given type,
concurrency, and holdabilityResultSet
CallableStatement prepareCall(String sql, int resultSetType, int resultSetConcurrency, int resultSetHoldability) throws SQLException
CallableStatement
object that will generate
ResultSet
objects with the given type and concurrency.
This method is the same as the prepareCall
method
above, but it allows the default result set
type, result set concurrency type and holdability to be overridden.SQLException
- if a database access error occurs, this
method is called on a closed connection
or the given parameters are not ResultSet
constants indicating type, concurrency, and holdabilitySQLFeatureNotSupportedException
- if the JDBC driver does not support
this method or this method is not supported for the specified result
set type, result set holdability and result set concurrency.sql
- a String
object that is the SQL statement to
be sent to the database; may contain on or more '?' parametersresultSetType
- one of the following ResultSet
constants:
ResultSet.TYPE_FORWARD_ONLY
,
ResultSet.TYPE_SCROLL_INSENSITIVE
, or
ResultSet.TYPE_SCROLL_SENSITIVE
resultSetConcurrency
- one of the following ResultSet
constants:
ResultSet.CONCUR_READ_ONLY
or
ResultSet.CONCUR_UPDATABLE
resultSetHoldability
- one of the following ResultSet
constants:
ResultSet.HOLD_CURSORS_OVER_COMMIT
or
ResultSet.CLOSE_CURSORS_AT_COMMIT
CallableStatement
object, containing the
pre-compiled SQL statement, that will generate
ResultSet
objects with the given type,
concurrency, and holdabilityResultSet
PreparedStatement prepareStatement(String sql, int autoGeneratedKeys) throws SQLException
PreparedStatement
object that has
the capability to retrieve auto-generated keys. The given constant
tells the driver whether it should make auto-generated keys
available for retrieval. This parameter is ignored if the SQL statement
is not an INSERT
statement, or an SQL statement able to return
auto-generated keys (the list of such statements is vendor-specific).
Note: This method is optimized for handling
parametric SQL statements that benefit from precompilation. If
the driver supports precompilation,
the method prepareStatement
will send
the statement to the database for precompilation. Some drivers
may not support precompilation. In this case, the statement may
not be sent to the database until the PreparedStatement
object is executed. This has no direct effect on users; however, it does
affect which methods throw certain SQLExceptions.
Result sets created using the returned PreparedStatement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
The holdability of the created result sets can be determined by
calling getHoldability()
.
SQLException
- if a database access error occurs, this
method is called on a closed connection
or the given parameter is not a Statement
constant indicating whether auto-generated keys should be
returnedSQLFeatureNotSupportedException
- if the JDBC driver does not support
this method with a constant of Statement.RETURN_GENERATED_KEYSsql
- an SQL statement that may contain one or more '?' IN
parameter placeholdersautoGeneratedKeys
- a flag indicating whether auto-generated keys
should be returned; one of
Statement.RETURN_GENERATED_KEYS
or
Statement.NO_GENERATED_KEYS
PreparedStatement
object, containing the
pre-compiled SQL statement, that will have the capability of
returning auto-generated keysPreparedStatement prepareStatement(String sql, int[] columnIndexes) throws SQLException
PreparedStatement
object capable
of returning the auto-generated keys designated by the given array.
This array contains the indexes of the columns in the target
table that contain the auto-generated keys that should be made
available. The driver will ignore the array if the SQL statement
is not an INSERT
statement, or an SQL statement able to return
auto-generated keys (the list of such statements is vendor-specific).
An SQL statement with or without IN parameters can be
pre-compiled and stored in a PreparedStatement
object. This
object can then be used to efficiently execute this statement
multiple times.
Note: This method is optimized for handling
parametric SQL statements that benefit from precompilation. If
the driver supports precompilation,
the method prepareStatement
will send
the statement to the database for precompilation. Some drivers
may not support precompilation. In this case, the statement may
not be sent to the database until the PreparedStatement
object is executed. This has no direct effect on users; however, it does
affect which methods throw certain SQLExceptions.
Result sets created using the returned PreparedStatement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
The holdability of the created result sets can be determined by
calling getHoldability()
.
SQLException
- if a database access error occurs
or this method is called on a closed connectionSQLFeatureNotSupportedException
- if the JDBC driver does not support
this methodsql
- an SQL statement that may contain one or more '?' IN
parameter placeholderscolumnIndexes
- an array of column indexes indicating the columns
that should be returned from the inserted row or rowsPreparedStatement
object, containing the
pre-compiled statement, that is capable of returning the
auto-generated keys designated by the given array of column
indexesPreparedStatement prepareStatement(String sql, String[] columnNames) throws SQLException
PreparedStatement
object capable
of returning the auto-generated keys designated by the given array.
This array contains the names of the columns in the target
table that contain the auto-generated keys that should be returned.
The driver will ignore the array if the SQL statement
is not an INSERT
statement, or an SQL statement able to return
auto-generated keys (the list of such statements is vendor-specific).
An SQL statement with or without IN parameters can be
pre-compiled and stored in a PreparedStatement
object. This
object can then be used to efficiently execute this statement
multiple times.
Note: This method is optimized for handling
parametric SQL statements that benefit from precompilation. If
the driver supports precompilation,
the method prepareStatement
will send
the statement to the database for precompilation. Some drivers
may not support precompilation. In this case, the statement may
not be sent to the database until the PreparedStatement
object is executed. This has no direct effect on users; however, it does
affect which methods throw certain SQLExceptions.
Result sets created using the returned PreparedStatement
object will by default be type TYPE_FORWARD_ONLY
and have a concurrency level of CONCUR_READ_ONLY
.
The holdability of the created result sets can be determined by
calling getHoldability()
.
SQLException
- if a database access error occurs
or this method is called on a closed connectionSQLFeatureNotSupportedException
- if the JDBC driver does not support
this methodsql
- an SQL statement that may contain one or more '?' IN
parameter placeholderscolumnNames
- an array of column names indicating the columns
that should be returned from the inserted row or rowsPreparedStatement
object, containing the
pre-compiled statement, that is capable of returning the
auto-generated keys designated by the given array of column
namesClob createClob() throws SQLException
Clob
interface. The object
returned initially contains no data. The setAsciiStream
,
setCharacterStream
and setString
methods of
the Clob
interface may be used to add data to the Clob
.SQLException
- if an object that implements the
Clob
interface can not be constructed, this method is
called on a closed connection or a database access error occurs.SQLFeatureNotSupportedException
- if the JDBC driver does not support
this data typeClob
interfaceBlob createBlob() throws SQLException
Blob
interface. The object
returned initially contains no data. The setBinaryStream
and
setBytes
methods of the Blob
interface may be used to add data to
the Blob
.SQLException
- if an object that implements the
Blob
interface can not be constructed, this method is
called on a closed connection or a database access error occurs.SQLFeatureNotSupportedException
- if the JDBC driver does not support
this data typeBlob
interfaceNClob createNClob() throws SQLException
NClob
interface. The object
returned initially contains no data. The setAsciiStream
,
setCharacterStream
and setString
methods of the NClob
interface may
be used to add data to the NClob
.SQLException
- if an object that implements the
NClob
interface can not be constructed, this method is
called on a closed connection or a database access error occurs.SQLFeatureNotSupportedException
- if the JDBC driver does not support
this data typeNClob
interfaceSQLXML createSQLXML() throws SQLException
SQLXML
interface. The object
returned initially contains no data. The createXmlStreamWriter
object and
setString
method of the SQLXML
interface may be used to add data to the SQLXML
object.SQLException
- if an object that implements the SQLXML
interface can not
be constructed, this method is
called on a closed connection or a database access error occurs.SQLFeatureNotSupportedException
- if the JDBC driver does not support
this data typeSQLXML
interfaceboolean isValid(int timeout) throws SQLException
The query submitted by the driver to validate the connection shall be executed in the context of the current transaction.
SQLException
- if the value supplied for timeout
is less then 0timeout
- - The time in seconds to wait for the database operation
used to validate the connection to complete. If
the timeout period expires before the operation
completes, this method returns false. A value of
0 indicates a timeout is not applied to the
database operation.
DatabaseMetaData.getClientInfoProperties()
void setClientInfo(String name, String value) throws SQLClientInfoException
Applications may use the DatabaseMetaData.getClientInfoProperties
method to determine the client info properties supported by the driver
and the maximum length that may be specified for each property.
The driver stores the value specified in a suitable location in the database. For example in a special register, session parameter, or system table column. For efficiency the driver may defer setting the value in the database until the next time a statement is executed or prepared. Other than storing the client information in the appropriate place in the database, these methods shall not alter the behavior of the connection in anyway. The values supplied to these methods are used for accounting, diagnostics and debugging purposes only.
The driver shall generate a warning if the client info name specified is not recognized by the driver.
If the value specified to this method is greater than the maximum
length for the property the driver may either truncate the value and
generate a warning or generate a SQLClientInfoException
. If the driver
generates a SQLClientInfoException
, the value specified was not set on the
connection.
The following are standard client info properties. Drivers are not required to support these properties however if the driver supports a client info property that can be described by one of the standard properties, the standard property name should be used.
SQLClientInfoException
- if the database server returns an error while
setting the client info value on the database server or this method
is called on a closed connection
name
- The name of the client info property to setvalue
- The value to set the client info property to. If the
value is null, the current value of the specified
property is cleared.
void setClientInfo(Properties properties) throws SQLClientInfoException
Properties
object contains the names and values of the client info
properties to be set. The set of client info properties contained in
the properties list replaces the current set of client info properties
on the connection. If a property that is currently set on the
connection is not present in the properties list, that property is
cleared. Specifying an empty properties list will clear all of the
properties on the connection. See setClientInfo (String, String)
for
more information.
If an error occurs in setting any of the client info properties, a
SQLClientInfoException
is thrown. The SQLClientInfoException
contains information indicating which client info properties were not set.
The state of the client information is unknown because
some databases do not allow multiple client info properties to be set
atomically. For those databases, one or more properties may have been
set before the error occurred.
SQLClientInfoException
- if the database server returns an error while
setting the clientInfo values on the database server or this method
is called on a closed connectionproperties
- the list of client info properties to set
setClientInfo(String, String)
String getClientInfo(String name) throws SQLException
Applications may use the DatabaseMetaData.getClientInfoProperties
method to determine the client info properties supported by the driver.
SQLException
- if the database server returns an error when
fetching the client info value from the database
or this method is called on a closed connection
name
- The name of the client info property to retrieve
DatabaseMetaData.getClientInfoProperties()
Properties getClientInfo() throws SQLException
SQLException
- if the database server returns an error when
fetching the client info values from the database
or this method is called on a closed connection
Properties
object that contains the name and current value of
each of the client info properties supported by the driver.
Array createArrayOf(String typeName, Object[] elements) throws SQLException
Note: When createArrayOf
is used to create an array object
that maps to a primitive data type, then it is implementation-defined
whether the Array
object is an array of that primitive
data type or an array of Object
.
Note: The JDBC driver is responsible for mapping the elements
Object
array to the default JDBC SQL type defined in
java.sql.Types for the given class of Object
. The default
mapping is specified in Appendix B of the JDBC specification. If the
resulting JDBC type is not the appropriate type for the given typeName then
it is implementation defined whether an SQLException
is
thrown or the driver supports the resulting conversion.
SQLException
- if a database error occurs, the JDBC type is not
appropriate for the typeName and the conversion is not supported, the typeName is null or this method is called on a closed connectionSQLFeatureNotSupportedException
- if the JDBC driver does not support this data typetypeName
- the SQL name of the type the elements of the array map to. The typeName is a
database-specific name which may be the name of a built-in type, a user-defined type or a standard SQL type supported by this database. This
is the value returned by Array.getBaseTypeName
elements
- the elements that populate the returned objectStruct createStruct(String typeName, Object[] attributes) throws SQLException
SQLException
- if a database error occurs, the typeName is null or this method is called on a closed connectionSQLFeatureNotSupportedException
- if the JDBC driver does not support this data typetypeName
- the SQL type name of the SQL structured type that this Struct
object maps to. The typeName is the name of a user-defined type that
has been defined for this database. It is the value returned by
Struct.getSQLTypeName
.attributes
- the attributes that populate the returned objectvoid setSchema(String schema) throws SQLException
If the driver does not support schemas, it will silently ignore this request.
Calling setSchema
has no effect on previously created or prepared
Statement
objects. It is implementation defined whether a DBMS
prepare operation takes place immediately when the Connection
method prepareStatement
or prepareCall
is invoked.
For maximum portability, setSchema
should be called before a
Statement
is created or prepared.
SQLException
- if a database access error occurs
or this method is called on a closed connectionschema
- the name of a schema in which to workgetSchema()
String getSchema() throws SQLException
Connection
object's current schema name.SQLException
- if a database access error occurs
or this method is called on a closed connectionnull
if there is nonesetSchema(java.lang.String)
void abort(Executor executor) throws SQLException
abort
results in:
SQLException
.
Calling abort
marks the connection closed and releases any
resources. Calling abort
on a closed connection is a
no-op.
It is possible that the aborting and releasing of the resources that are
held by the connection can take an extended period of time. When the
abort
method returns, the connection will have been marked as
closed and the Executor
that was passed as a parameter to abort
may still be executing tasks to release resources.
This method checks to see that there is an SQLPermission
object before allowing the method to proceed. If a
SecurityManager
exists and its
checkPermission
method denies calling abort
,
this method throws a
java.lang.SecurityException
.
SQLException
- if a database access error occurs or
the executor
is null
,SecurityException
- if a security manager exists and its
checkPermission
method denies calling abort
executor
- The Executor
implementation which will
be used by abort
.SecurityManager.checkPermission(java.security.Permission)
,
Executor
void setNetworkTimeout(Executor executor, int milliseconds) throws SQLException
Connection
or
objects created from the Connection
will wait for the database to reply to any one request. If any
request remains unanswered, the waiting method will
return with a SQLException
, and the Connection
or objects created from the Connection
will be marked as
closed. Any subsequent use of
the objects, with the exception of the close
,
isClosed
or Connection.isValid
methods, will result in a SQLException
.
Note: This method is intended to address a rare but serious
condition where network partitions can cause threads issuing JDBC calls
to hang uninterruptedly in socket reads, until the OS TCP-TIMEOUT
(typically 10 minutes). This method is related to the
abort()
method which provides an administrator
thread a means to free any such threads in cases where the
JDBC connection is accessible to the administrator thread.
The setNetworkTimeout
method will cover cases where
there is no administrator thread, or it has no access to the
connection. This method is severe in it's effects, and should be
given a high enough value so it is never triggered before any more
normal timeouts, such as transaction timeouts.
JDBC driver implementations may also choose to support the
setNetworkTimeout
method to impose a limit on database
response time, in environments where no network is present.
Drivers may internally implement some or all of their API calls with multiple internal driver-database transmissions, and it is left to the driver implementation to determine whether the limit will be applied always to the response to the API call, or to any single request made during the API call.
This method can be invoked more than once, such as to set a limit for an area of JDBC code, and to reset to the default on exit from this area. Invocation of this method has no impact on already outstanding requests.
The Statement.setQueryTimeout()
timeout value is independent of the
timeout value specified in setNetworkTimeout
. If the query timeout
expires before the network timeout then the
statement execution will be canceled. If the network is still
active the result will be that both the statement and connection
are still usable. However if the network timeout expires before
the query timeout or if the statement timeout fails due to network
problems, the connection will be marked as closed, any resources held by
the connection will be released and both the connection and
statement will be unusable.
When the driver determines that the setNetworkTimeout
timeout
value has expired, the JDBC driver marks the connection
closed and releases any resources held by the connection.
This method checks to see that there is an SQLPermission
object before allowing the method to proceed. If a
SecurityManager
exists and its
checkPermission
method denies calling
setNetworkTimeout
, this method throws a
java.lang.SecurityException
.
SQLException
- if a database access error occurs, this
method is called on a closed connection,
the executor
is null
,
or the value specified for seconds
is less than 0.SecurityException
- if a security manager exists and its
checkPermission
method denies calling
setNetworkTimeout
.SQLFeatureNotSupportedException
- if the JDBC driver does not support
this methodexecutor
- The Executor
implementation which will
be used by setNetworkTimeout
.milliseconds
- The time in milliseconds to wait for the database
operation
to complete. If the JDBC driver does not support milliseconds, the
JDBC driver will round the value up to the nearest second. If the
timeout period expires before the operation
completes, a SQLException will be thrown.
A value of 0 indicates that there is not timeout for database operations.SecurityManager.checkPermission(java.security.Permission)
,
Statement.setQueryTimeout(int)
,
getNetworkTimeout()
,
abort(java.util.concurrent.Executor)
,
Executor
int getNetworkTimeout() throws SQLException
SQLException
is thrown.SQLException
- if a database access error occurs or
this method is called on a closed Connection
SQLFeatureNotSupportedException
- if the JDBC driver does not support
this methodsetNetworkTimeout(java.util.concurrent.Executor, int)
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