Class PoolableConnection

java.lang.Object

org.datanucleus.store.rdbms.datasource.dbcp2.AbandonedTrace

org.datanucleus.store.rdbms.datasource.dbcp2.DelegatingConnection<Connection>

org.datanucleus.store.rdbms.datasource.dbcp2.PoolableConnection

All Implemented Interfaces:

AutoCloseable, Connection, Wrapper, TrackedUse, PoolableConnectionMXBean

public class PoolableConnection
extends DelegatingConnection<Connection>
implements PoolableConnectionMXBean

A delegating connection that, rather than closing the underlying connection, returns itself to an ObjectPool when closed.

Since:

2.0

Field Summary

Fields

Modifier and Type	Field	Description
private final Collection<String>	disconnectionSqlCodes	SQL_STATE codes considered to signal fatal conditions.
private final boolean	fastFailValidation	Whether or not to fast fail validation after fatal connection errors
private boolean	fatalSqlExceptionThrown	Indicate that unrecoverable SQLException was thrown when using this connection.
private final ObjectNameWrapper	jmxObjectName
private String	lastValidationSql
private static MBeanServer	MBEAN_SERVER
private final ObjectPool<PoolableConnection>	pool	The pool to which I should return.
private PreparedStatement	validationPreparedStatement

Fields inherited from interface Connection

TRANSACTION_NONE, TRANSACTION_READ_COMMITTED, TRANSACTION_READ_UNCOMMITTED, TRANSACTION_REPEATABLE_READ, TRANSACTION_SERIALIZABLE

Constructor Summary

Constructors

Constructor	Description
PoolableConnection(Connection conn, ObjectPool<PoolableConnection> pool, ObjectName jmxName)
PoolableConnection(Connection conn, ObjectPool<PoolableConnection> pool, ObjectName jmxObjectName, Collection<String> disconnectSqlCodes, boolean fastFailValidation)

Method Summary

Modifier and Type	Method	Description
void	close()	Returns me to my pool.
Collection<String>	getDisconnectionSqlCodes()
String	getToString()	Expose the DelegatingConnection.toString() method via a bean getter so it can be read as a property via JMX.
protected void	handleException(SQLException e)
boolean	isClosed()
private boolean	isDisconnectionSqlException(SQLException e)	Checks the SQLState of the input exception and any nested SQLExceptions it wraps.
boolean	isFastFailValidation()
protected void	passivate()
void	reallyClose()	Actually close my underlying Connection.
void	validate(String sql, int timeoutSeconds)	Validates the connection, using the following algorithm: If fastFailValidation (constructor argument) is true and this connection has previously thrown a fatal disconnection exception, a SQLException is thrown. If sql is null, the driver's #isValid(timeout) is called.

Methods inherited from class DelegatingConnection

abort, activate, checkOpen, clearCachedState, clearWarnings, closeInternal, commit, createArrayOf, createBlob, createClob, createNClob, createSQLXML, createStatement, createStatement, createStatement, createStruct, getAutoCommit, getCacheState, getCatalog, getClientInfo, getClientInfo, getDefaultQueryTimeout, getDelegate, getDelegateInternal, getHoldability, getInnermostDelegate, getInnermostDelegateInternal, getMetaData, getNetworkTimeout, getSchema, getTransactionIsolation, getTypeMap, getWarnings, handleExceptionNoThrow, innermostDelegateEquals, isClosedInternal, isReadOnly, isValid, isWrapperFor, nativeSQL, prepareCall, prepareCall, prepareCall, prepareStatement, prepareStatement, prepareStatement, prepareStatement, prepareStatement, prepareStatement, releaseSavepoint, rollback, rollback, setAutoCommit, setCacheState, setCatalog, setClientInfo, setClientInfo, setClosedInternal, setDefaultQueryTimeout, setDelegate, setHoldability, setNetworkTimeout, setReadOnly, setSavepoint, setSavepoint, setSchema, setTransactionIsolation, setTypeMap, toString, unwrap

Methods inherited from class AbandonedTrace

addTrace, clearTrace, getLastUsed, getTrace, removeThisTrace, removeTrace, setLastUsed, setLastUsed

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface Connection

beginRequest, endRequest, setShardingKey, setShardingKey, setShardingKeyIfValid, setShardingKeyIfValid

Methods inherited from interface PoolableConnectionMXBean

clearCachedState, clearWarnings, getAutoCommit, getCacheState, getCatalog, getHoldability, getSchema, getTransactionIsolation, isReadOnly, setAutoCommit, setCacheState, setCatalog, setHoldability, setReadOnly, setSchema, setTransactionIsolation

Field Details

MBEAN_SERVER

private static MBeanServer MBEAN_SERVER

pool

private final ObjectPool<PoolableConnection> pool

The pool to which I should return.

jmxObjectName

private final ObjectNameWrapper jmxObjectName

validationPreparedStatement

private PreparedStatement validationPreparedStatement

lastValidationSql

private String lastValidationSql

fatalSqlExceptionThrown

private boolean fatalSqlExceptionThrown

Indicate that unrecoverable SQLException was thrown when using this connection. Such a connection should be considered broken and not pass validation in the future.

disconnectionSqlCodes

private final Collection<String> disconnectionSqlCodes

SQL_STATE codes considered to signal fatal conditions. Overrides the defaults in Utils.DISCONNECTION_SQL_CODES (plus anything starting with Utils.DISCONNECTION_SQL_CODE_PREFIX).

fastFailValidation

private final boolean fastFailValidation

Whether or not to fast fail validation after fatal connection errors

Constructor Details

PoolableConnection

public PoolableConnection(Connection conn,
 ObjectPool<PoolableConnection> pool,
 ObjectName jmxObjectName,
 Collection<String> disconnectSqlCodes,
 boolean fastFailValidation)

Parameters:

conn - my underlying connection

pool - the pool to which I should return when closed

jmxObjectName - JMX name

disconnectSqlCodes - SQL_STATE codes considered fatal disconnection errors

fastFailValidation - true means fatal disconnection errors cause subsequent validations to fail immediately (no attempt to run query or isValid)

PoolableConnection

public PoolableConnection(Connection conn,
 ObjectPool<PoolableConnection> pool,
 ObjectName jmxName)

Parameters:

conn - my underlying connection

pool - the pool to which I should return when closed

jmxName - JMX name

Method Details

passivate

protected void passivate()
                  throws SQLException

Overrides:

passivate in class DelegatingConnection<Connection>

Throws:

SQLException

isClosed

public boolean isClosed()
                 throws SQLException

This method should not be used by a client to determine whether or not a connection should be return to the connection pool (by calling close()). Clients should always attempt to return a connection to the pool once it is no longer required.

Specified by:

isClosed in interface Connection

Specified by:

isClosed in interface PoolableConnectionMXBean

Overrides:

isClosed in class DelegatingConnection<Connection>

Throws:

SQLException

close

public void close()
           throws SQLException

Returns me to my pool.

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Connection

Specified by:

close in interface PoolableConnectionMXBean

Overrides:

close in class DelegatingConnection<Connection>

Throws:

SQLException

reallyClose

public void reallyClose()
                 throws SQLException

Actually close my underlying Connection.

Specified by:

reallyClose in interface PoolableConnectionMXBean

Throws:

SQLException

getToString

public String getToString()

Expose the DelegatingConnection.toString() method via a bean getter so it can be read as a property via JMX.

Specified by:

getToString in interface PoolableConnectionMXBean

validate

public void validate(String sql,
 int timeoutSeconds)
              throws SQLException

Validates the connection, using the following algorithm:

1. If fastFailValidation (constructor argument) is true and this connection has previously thrown a fatal disconnection exception, a SQLException is thrown.
2. If sql is null, the driver's #isValid(timeout) is called. If it returns false, SQLException is thrown; otherwise, this method returns successfully.
3. If sql is not null, it is executed as a query and if the resulting ResultSet contains at least one row, this method returns successfully. If not, SQLException is thrown.

Parameters:

sql - The validation SQL query.

timeoutSeconds - The validation timeout in seconds.

Throws:

SQLException - Thrown when validation fails or an SQLException occurs during validation

isDisconnectionSqlException

private boolean isDisconnectionSqlException(SQLException e)

Checks the SQLState of the input exception and any nested SQLExceptions it wraps.

If disconnectionSqlCodes has been set, sql states are compared to those in the configured list of fatal exception codes. If this property is not set, codes are compared against the default codes in Utils.DISCONNECTION_SQL_CODES and in this case anything starting with #{link Utils.DISCONNECTION_SQL_CODE_PREFIX} is considered a disconnection.

Parameters:

e - SQLException to be examined

Returns:

true if the exception signals a disconnection

handleException

protected void handleException(SQLException e)
                        throws SQLException

Overrides:

handleException in class DelegatingConnection<Connection>

Throws:

SQLException

getDisconnectionSqlCodes

public Collection<String> getDisconnectionSqlCodes()

Returns:

The disconnection SQL codes.

Since:

2.6.0

isFastFailValidation

public boolean isFastFailValidation()

Returns:

Whether to fail-fast.

Since:

2.6.0