com.gargoylesoftware.base.resource.jdbc
public final class ConnectionWrapper extends Object implements Connection, ManagedResource
The contract with JDBC says that result sets must be closed before statements and statements must be closed before connections but java does not enforce this contract. It is quite possible to close a connection while statements and result sets are still open. While some database drivers handle this condition nicely, others will start failing in undefined ways when this happens.
This wrapper class is a solution to this problem. If the connection is only accessed through the wrapper then the wrapper will ensure that everything is closed in the correct order. It will also ensure that the various jdbc objects (connections, statements, result sets and metadata) cannot be used after they are closed.
This class was created for the JDBCResourceFactory but can be used by itself.
Version: $Revision: 1.4 $
Field Summary | |
---|---|
Connection | delegate_ |
boolean | isOpen_ |
List | openDatabaseMetaData_ |
List | openStatements_ |
String | resourceFactoryName_ |
Constructor Summary | |
---|---|
ConnectionWrapper(Connection connection)
Create a new connection wrapper
|
Method Summary | |
---|---|
void | checkConnection()
Check to see if the connection is still open. |
void | clearWarnings()
Clears all warnings reported for this Connection object.
|
void | close()
Releases a Connection's database and JDBC resources immediately instead
of waiting for them to be automatically released. |
void | closeAnyOpenMetaDatas()
Close any open DatabaseMetaData objects
|
void | closeAnyOpenStatements()
Close any open statements
|
void | commit()
Makes all changes made since the previous commit/rollback permanent and
releases any database locks currently held by the Connection. |
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.
|
boolean | getAutoCommit()
Gets the current auto-commit state.
|
String | getCatalog()
Returns the Connection's current catalog name.
|
Connection | getDelegate()
Return the wrapped connection
|
int | getHoldability()
Retrieves the current holdability of ResultSet objects
created using this Connection object.
|
DatabaseMetaData | getMetaData()
Gets the metadata regarding this connection's database. |
int | getOpenStatementCount()
Return the number of statements that are currently open. |
String | getResourceFactoryName()
Return the name of the factory that allocated this connection
|
int | getTransactionIsolation()
Gets this Connection's current transaction isolation level.
|
Map | getTypeMap()
Gets the type map object associated with this connection. |
SQLWarning | getWarnings()
Returns the first warning reported by calls on this Connection. |
boolean | isClosed()
Tests to see if a Connection is closed.
|
boolean | isReadOnly()
Tests to see if the connection is in read-only mode.
|
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 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, 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, 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 given Savepoint object from the current
transaction. |
void | rollback()
Drops all changes made since the previous commit/rollback and releases
any database locks currently held by this Connection. |
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. |
void | setCatalog(String catalog)
Sets a catalog name in order to select a subspace of this Connection's
database in which to work. |
void | setHoldability(int holdability)
Changes the holdability of ResultSet objects
created using this Connection object to the given
holdability.
|
void | setReadOnly(boolean readOnly)
Puts this connection in read-only mode as a hint to enable database
optimizations. |
void | setResourceFactoryName(String name)
Set the name of the factory that allocated this connection
|
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 | setTransactionIsolation(int level)
Attempts to change the transaction isolation level to the one given. |
void | setTypeMap(Map map)
Installs the given type map as the type map for this connection. |
Parameters: connection The connection that we are wrapping
Throws: SQLException
Connection
object.
After a call to this method, the method getWarnings
returns
null until a new warning is reported for this Connection.
Throws: SQLException if a database access error occurs
Note: A Connection is automatically closed when it is garbage collected. Certain fatal errors also result in a closed Connection.
Throws: SQLException if a database access error occurs
Throws: SQLException If an error occurs
Throws: SQLException If an error occurs
Throws: SQLException if a database access error occurs
See Also: ConnectionWrapper
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 is more efficient to use a PreparedStatement
object.
Result sets created using the returned Statement
object
will by default have forward-only type and read-only concurrency.
Returns: a new Statement object
Throws: SQLException if a database access error occurs
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 result set concurrency type to be overridden.
Parameters: resultSetType a result set type; see ResultSet.TYPE_XXX resultSetConcurrency a concurrency type; see ResultSet.CONCUR_XXX
Returns: a new Statement object
Throws: SQLException if a database access error occurs
Since: 1.2
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.
Parameters: 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
Returns: a new Statement
object that will generate
ResultSet
objects with the given type,
concurrency, and holdability
Throws: SQLException if a database access error occurs
or the given parameters are not ResultSet
constants indicating type, concurrency, and holdability
Since: 1.4
See Also: java.sql.ResultSet
Returns: the current state of auto-commit mode
Throws: SQLException if a database access error occurs
See Also: ConnectionWrapper
Returns: the current catalog name or null
Throws: SQLException if a database access error occurs
Returns: The wrapped connection
ResultSet
objects
created using this Connection
object.
Returns: the holdability, one of
ResultSet.HOLD_CURSORS_OVER_COMMIT
or
ResultSet.CLOSE_CURSORS_AT_COMMIT
Throws: SQLException if a database access occurs
Since: 1.4
See Also: ConnectionWrapper java.sql.ResultSet
Returns: a DatabaseMetaData object for this Connection
Throws: SQLException if a database access error occurs
Returns: The number of statements that are currently open.
Returns: The name of the factory
Returns: the current TRANSACTION_* mode value
Throws: SQLException if a database access error occurs
Returns: the java.util.Map
object associated with this
Connection
object
Throws: SQLException If a sql error occurs
Since: 1.2
Note: Subsequent warnings will be chained to this SQLWarning.
Returns: the first SQLWarning or null
Throws: SQLException if a database access error occurs
Returns: true if the connection is closed; false if it's still open
Throws: SQLException if a database access error occurs
Returns: true if connection is read-only and false otherwise
Throws: SQLException if a database access error occurs
Parameters: sql a SQL statement that may contain one or more '?' parameter placeholders
Returns: the native form of this statement
Throws: SQLException if a database access error occurs
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 will have forward-only type and read-only concurrency,
by default.
Parameters: sql a SQL statement that may contain one or more '?' parameter placeholders. Typically this statement is a JDBC function call escape string.
Returns: a new CallableStatement object containing the pre-compiled SQL statement
Throws: SQLException if a database access error occurs
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 result set concurrency type to be
overridden.
Parameters: sql a SQL statement that may contain one or more '?' parameter placeholders. Typically this statement is a JDBC function call escape string. resultSetType a result set type; see ResultSet.TYPE_XXX resultSetConcurrency a concurrency type; see ResultSet.CONCUR_XXX
Returns: a new CallableStatement object containing the pre-compiled SQL statement
Throws: SQLException if a database access error occurs
Since: 1.2
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.
Parameters: sql a String
object that is the SQL statement to
be sent to the database; may contain on or more ? parameters 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
Returns: a new CallableStatement
object, containing the
pre-compiled SQL statement, that will generate
ResultSet
objects with the given type,
concurrency, and holdability
Throws: SQLException if a database access error occurs
or the given parameters are not ResultSet
constants indicating type, concurrency, and holdability
Since: 1.4
See Also: java.sql.ResultSet
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
is executed. This
has no direct effect on users; however, it does affect which method
throws certain SQLExceptions.
Result sets created using the returned PreparedStatement will have forward-only type and read-only concurrency, by default.
Parameters: sql a SQL statement that may contain one or more '?' IN parameter placeholders
Returns: a new PreparedStatement object containing the pre-compiled statement
Throws: SQLException if a database access error occurs
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 result set concurrency
type to be overridden.
Parameters: sql a SQL statement that may contain one or more '?' parameter placeholders. Typically this statement is a JDBC function call escape string. resultSetType a result set type; see ResultSet.TYPE_XXX resultSetConcurrency a concurrency type; see ResultSet.CONCUR_XXX
Returns: a new PreparedStatement object containing the pre-compiled SQL statement
Throws: SQLException if a database access error occurs
Since: 1.2
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.
Parameters: sql a String
object that is the SQL statement to
be sent to the database; may contain one or more ? IN
parameters 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
Returns: a new PreparedStatement
object, containing the
pre-compiled SQL statement, that will generate
ResultSet
objects with the given type,
concurrency, and holdability
Throws: SQLException if a database access error occurs
or the given parameters are not ResultSet
constants indicating type, concurrency, and holdability
Since: 1.4
See Also: java.sql.ResultSet
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.
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
.
Parameters: sql an SQL statement that may contain one or more '?' IN
parameter placeholders autoGeneratedKeys a flag indicating whether auto-generated keys
should be returned; one of
Statement.RETURN_GENERATED_KEYS
or
Statement.NO_GENERATED_KEYS
Returns: a new PreparedStatement
object, containing the
pre-compiled SQL statement, that will have the capability of
returning auto-generated keys
Throws: SQLException if a database access error occurs
or the given parameter is not a Statement
constant indicating whether auto-generated keys should be
returned
Since: 1.4
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. This array is ignored if the SQL
statement is not an INSERT
statement.
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
.
Parameters: sql an SQL statement that may contain one or more '?' IN parameter placeholders columnIndexes an array of column indexes indicating the columns that should be returned from the inserted row or rows
Returns: a new PreparedStatement
object, containing the
pre-compiled statement, that is capable of returning the
auto-generated keys designated by the given array of column
indexes
Throws: SQLException if a database access error occurs
Since: 1.4
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.
This array is ignored if the SQL
statement is not an INSERT
statement.
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
.
Parameters: sql an SQL statement that may contain one or more '?' IN parameter placeholders columnNames an array of column names indicating the columns that should be returned from the inserted row or rows
Returns: a new PreparedStatement
object, containing the
pre-compiled statement, that is capable of returning the
auto-generated keys designated by the given array of column
names
Throws: SQLException if a database access error occurs
Since: 1.4
Savepoint
object from the current
transaction. Any reference to the savepoint after it have been removed
will cause an SQLException
to be thrown.
Parameters: savepoint the Savepoint
object to be removed
Throws: SQLException if a database access error occurs or
the given Savepoint
object is not a valid
savepoint in the current transaction
Since: 1.4
Throws: SQLException if a database access error occurs
See Also: ConnectionWrapper
Savepoint
object
was set.
This method should be used only when auto-commit has been disabled.
Parameters: savepoint the Savepoint
object to roll back to
Throws: SQLException if a database access error occurs,
the Savepoint
object is no longer valid,
or this Connection
object is currently in
auto-commit mode
Since: 1.4
See Also: Savepoint
commit
or the method rollback
. By
default, new connections are in auto-commit mode. The commit occurs when the statement completes or the next execute occurs, whichever comes first. In the case of statements returning a ResultSet, the statement completes when the last row of the ResultSet has been retrieved or the ResultSet has been closed. In advanced cases, a single statement may return multiple results as well as output parameter values. In these cases the commit occurs when all results and output parameter values have been retrieved.
Parameters: autoCommit true enables auto-commit; false disables auto-commit.
Throws: SQLException if a database access error occurs
Parameters: catalog The catalog name
Throws: SQLException if a database access error occurs
ResultSet
objects
created using this Connection
object to the given
holdability.
Parameters: holdability a ResultSet
holdability constant; one of
ResultSet.HOLD_CURSORS_OVER_COMMIT
or
ResultSet.CLOSE_CURSORS_AT_COMMIT
Throws: SQLException if a database access occurs, the given parameter
is not a ResultSet
constant indicating holdability,
or the given holdability is not supported
Since: 1.4
See Also: ConnectionWrapper java.sql.ResultSet
Note: This method cannot be called while in the middle of a transaction.
Parameters: readOnly true enables read-only mode; false disables read-only mode.
Throws: SQLException if a database access error occurs
Parameters: name The name of the factory
Savepoint
object that represents it.
Returns: the new Savepoint
object
Throws: SQLException if a database access error occurs
or this Connection
object is currently in
auto-commit mode
Since: 1.4
See Also: Savepoint
Savepoint
object that represents it.
Parameters: name a String
containing the name of the savepoint
Returns: the new Savepoint
object
Throws: SQLException if a database access error occurs
or this Connection
object is currently in
auto-commit mode
Since: 1.4
See Also: Savepoint
Connection
are the
possible transaction isolation levels. Note: This method cannot be called while in the middle of a transaction.
Parameters: level one of the TRANSACTION_* isolation values with the exception of TRANSACTION_NONE; some databases may not support other values
Throws: SQLException if a database access error occurs
Parameters: map the java.util.Map
object to install as the
replacement for this Connection
object's default type
map
Throws: SQLException If a sql error occurs
Since: 1.2