Package org.apache.commons.dbcp2

# Class PoolableConnectionFactory

java.lang.Object
org.apache.commons.dbcp2.PoolableConnectionFactory

All Implemented Interfaces:
  `PooledObjectFactory<PoolableConnection>`

Direct Known Subclasses:
  `PoolableManagedConnectionFactory`

public class PoolableConnectionFactory extends Object implements PooledObjectFactory<PoolableConnection>
A `PooledObjectFactory` that creates `PoolableConnection`s.

Since:
  2.0

- ## Constructor Summary

  Constructors
  Constructor
  Description
  `PoolableConnectionFactory(ConnectionFactory connFactory, ObjectName dataSourceJmxObjectName)`
  Creates a new `PoolableConnectionFactory`.

- ## Method Summary

  Modifier and Type
  Method
  Description
  `void`
  `activateObject(PooledObject<PoolableConnection> p)`
  `void`
  `destroyObject(PooledObject<PoolableConnection> p)`
  `void`
  `destroyObject(PooledObject<PoolableConnection> p, DestroyMode mode)`
  `boolean`
  `getCacheState()`
  Gets the cache state to propagate in `makeObject()`.
  `ConnectionFactory`
  `getConnectionFactory()`
  Gets the connection factory.
  `protected AtomicLong`
  `getConnectionIndex()`
  Gets how many connections were created in `makeObject()`.
  `Collection<String>`
  `getConnectionInitSqls()`
  Gets the collection of initialization SQL statements.
  `ObjectName`
  `getDataSourceJmxName()`
  Gets data source JMX ObjectName.
  `ObjectName`
  `getDataSourceJmxObjectName()`
  Gets the data source JMX ObjectName.
  `Boolean`
  `getDefaultAutoCommit()`
  Gets the Default auto-commit value.
  `String`
  `getDefaultCatalog()`
  Gets the default catalog.
  `Integer`
  `getDefaultQueryTimeout()`
  Deprecated.
  Use `getDefaultQueryTimeoutDuration()`.
  `Duration`
  `getDefaultQueryTimeoutDuration()`
  Gets the default query timeout Duration.
  `Integer`
  `getDefaultQueryTimeoutSeconds()`
  Deprecated.
  Use `getDefaultQueryTimeoutDuration()`.
  `Boolean`
  `getDefaultReadOnly()`
  Gets the default read-only-value.
  `String`
  `getDefaultSchema()`
  Gets the default schema.
  `int`
  `getDefaultTransactionIsolation()`
  Gets the default transaction isolation.
  `Collection<String>`
  `getDisconnectionIgnoreSqlCodes()`
  Gets the collection of SQL State codes that are not considered fatal disconnection codes.
  `Collection<String>`
  `getDisconnectionSqlCodes()`
  Gets SQL State codes considered to signal fatal conditions.
  `Duration`
  `getMaxConnDuration()`
  Gets the Maximum connection duration.
  `long`
  `getMaxConnLifetimeMillis()`
  Gets the Maximum connection lifetime in milliseconds.
  `protected int`
  `getMaxOpenPreparedStatements()`
  Gets the maximum number of open prepared statements.
  `ObjectPool<PoolableConnection>`
  `getPool()`
  Returns the `ObjectPool` in which `Connection`s are pooled.
  `boolean`
  `getPoolStatements()`
  Tests whether to pool statements.
  `String`
  `getValidationQuery()`
  Gets the validation query.
  `Duration`
  `getValidationQueryTimeoutDuration()`
  Gets the query timeout in seconds.
  `int`
  `getValidationQueryTimeoutSeconds()`
  Deprecated.
  Use `getValidationQueryTimeoutDuration()`.
  `protected void`
  `initializeConnection(Connection conn)`
  Initializes the given connection with the collection of SQL statements set in `setConnectionInitSql(Collection)`.
  `boolean`
  `isAutoCommitOnReturn()`
  Tests whether to set auto-commit on `passivateObject(PooledObject)`.
  `boolean`
  `isEnableAutoCommitOnReturn()`
  Deprecated.
  Use `isAutoCommitOnReturn()`.
  `boolean`
  `isFastFailValidation()`
  True means that validation will fail immediately for connections that have previously thrown SQLExceptions with SQL State indicating fatal disconnection errors.
  `boolean`
  `isRollbackOnReturn()`
  Tests whether to rollback on return.
  `PooledObject<PoolableConnection>`
  `makeObject()`
  `void`
  `passivateObject(PooledObject<PoolableConnection> p)`
  `void`
  `setAutoCommitOnReturn(boolean autoCommitOnReturn)`
  Sets whether to set auto-commit on `passivateObject(PooledObject)`.
  `void`
  `setCacheState(boolean cacheState)`
  Sets the cache state to propagate in `makeObject()`.
  `void`
  `setClearStatementPoolOnReturn(boolean clearStatementPoolOnReturn)`
  Sets whether the pool of statements (which was enabled with `setPoolStatements(boolean)`) should be cleared when the connection is returned to its pool.
  `void`
  `setConnectionInitSql(Collection<String> connectionInitSqls)`
  Sets the SQL statements I use to initialize newly created `Connection`s.
  `void`
  `setDefaultAutoCommit(Boolean defaultAutoCommit)`
  Sets the default "auto commit" setting for borrowed `Connection`s
  `void`
  `setDefaultCatalog(String defaultCatalog)`
  Sets the default "catalog" setting for borrowed `Connection`s
  `void`
  `setDefaultQueryTimeout(Integer defaultQueryTimeoutSeconds)`
  Deprecated.
  Use `setDefaultQueryTimeout(Duration)`.
  `void`
  `setDefaultQueryTimeout(Duration defaultQueryTimeoutDuration)`
  Sets the query timeout Duration.
  `void`
  `setDefaultReadOnly(Boolean defaultReadOnly)`
  Sets the default "read only" setting for borrowed `Connection`s
  `void`
  `setDefaultSchema(String defaultSchema)`
  Sets the default "schema" setting for borrowed `Connection`s
  `void`
  `setDefaultTransactionIsolation(int defaultTransactionIsolation)`
  Sets the default "Transaction Isolation" setting for borrowed `Connection`s
  `void`
  `setDisconnectionIgnoreSqlCodes(Collection<String> disconnectionIgnoreSqlCodes)`
  Sets the disconnection SQL codes to ignore.
  `void`
  `setDisconnectionSqlCodes(Collection<String> disconnectionSqlCodes)`
  Sets the disconnection SQL codes.
  `void`
  `setEnableAutoCommitOnReturn(boolean autoCommitOnReturn)`
  Deprecated.
  `void`
  `setFastFailValidation(boolean fastFailValidation)`
  `void`
  `setMaxConn(Duration maxConnDuration)`
  Sets the maximum lifetime in milliseconds of a connection after which the connection will always fail activation, passivation and validation.
  `void`
  `setMaxConnLifetimeMillis(long maxConnLifetimeMillis)`
  Deprecated.
  Use `setMaxConn(Duration)`.
  `void`
  `setMaxOpenPreparedStatements(int maxOpenPreparedStatements)`
  Sets the maximum number of open prepared statements.
  `void`
  `setMaxOpenPrepatedStatements(int maxOpenPreparedStatements)`
  Deprecated.
  Use `setMaxOpenPreparedStatements(int)`.
  `void`
  `setPool(ObjectPool<PoolableConnection> pool)`
  Sets the `ObjectPool` in which to pool `Connection`s.
  `void`
  `setPoolStatements(boolean poolStatements)`
  Sets whether to pool statements.
  `void`
  `setRollbackOnReturn(boolean rollbackOnReturn)`
  Sets whether to rollback on return.
  `void`
  `setValidationQuery(String validationQuery)`
  Sets the query I use to `validate` `Connection`s.
  `void`
  `setValidationQueryTimeout(int validationQueryTimeoutSeconds)`
  Deprecated.
  `setValidationQueryTimeout(Duration)`.
  `void`
  `setValidationQueryTimeout(Duration validationQueryTimeoutDuration)`
  Sets the validation query timeout, the amount of time, that connection validation will wait for a response from the database when executing a validation query.
  `void`
  `validateConnection(PoolableConnection conn)`
  Validates the given connection if it is open.
  `boolean`
  `validateObject(PooledObject<PoolableConnection> p)`

  ### Methods inherited from class java.lang.Object

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

- ## Constructor Details

  - ### PoolableConnectionFactory

    public PoolableConnectionFactory(ConnectionFactory connFactory, ObjectName dataSourceJmxObjectName)
    Creates a new `PoolableConnectionFactory`.
    Parameters:
      `connFactory` - the `ConnectionFactory` from which to obtain base `Connection`s
      `dataSourceJmxObjectName` - The JMX object name, may be null.

- ## Method Details

  - ### activateObject

    public void activateObject(PooledObject<PoolableConnection> p) throws SQLException
    Specified by:
      `activateObject` in interface `PooledObjectFactory<PoolableConnection>`
    Throws:
      `SQLException`

  - ### destroyObject

    public void destroyObject(PooledObject<PoolableConnection> p) throws SQLException
    Specified by:
      `destroyObject` in interface `PooledObjectFactory<PoolableConnection>`
    Throws:
      `SQLException`

  - ### destroyObject

    public void destroyObject(PooledObject<PoolableConnection> p, DestroyMode mode) throws SQLException
    Specified by:
      `destroyObject` in interface `PooledObjectFactory<PoolableConnection>`
    Throws:
      `SQLException`
    Since:
      2.9.0

  - ### getCacheState

    public boolean getCacheState()
    Gets the cache state to propagate in `makeObject()`.
    Returns:
      The cache state.
    Since:
      2.6.0.

  - ### getConnectionFactory

    public ConnectionFactory getConnectionFactory()
    Gets the connection factory.
    Returns:
      The connection factory.
    Since:
      2.6.0.

  - ### getConnectionIndex

    protected AtomicLong getConnectionIndex()
    Gets how many connections were created in `makeObject()`.
    Returns:
      the connection count.

  - ### getConnectionInitSqls

    public Collection<String> getConnectionInitSqls()
    Gets the collection of initialization SQL statements.
    Returns:
      The collection of initialization SQL statements.
    Since:
      2.6.0

  - ### getDataSourceJmxName

    public ObjectName getDataSourceJmxName()
    Gets data source JMX ObjectName.
    Returns:
      The data source JMX ObjectName.
    Since:
      2.6.0.

  - ### getDataSourceJmxObjectName

    public ObjectName getDataSourceJmxObjectName()
    Gets the data source JMX ObjectName.
    Returns:
      The data source JMX ObjectName.
    Since:
      2.6.0

  - ### getDefaultAutoCommit

    public Boolean getDefaultAutoCommit()
    Gets the Default auto-commit value.
    Returns:
      The default auto-commit value.
    Since:
      2.6.0

  - ### getDefaultCatalog

    public String getDefaultCatalog()
    Gets the default catalog.
    Returns:
      The default catalog.
    Since:
      2.6.0

  - ### getDefaultQueryTimeout

    @Deprecated public Integer getDefaultQueryTimeout()
    Deprecated.
    Use `getDefaultQueryTimeoutDuration()`.
    Gets the default query timeout in seconds.
    Returns:
      The default query timeout in seconds.

  - ### getDefaultQueryTimeoutDuration

    public Duration getDefaultQueryTimeoutDuration()
    Gets the default query timeout Duration.
    Returns:
      The default query timeout Duration.
    Since:
      2.10.0

  - ### getDefaultQueryTimeoutSeconds

    @Deprecated public Integer getDefaultQueryTimeoutSeconds()
    Deprecated.
    Use `getDefaultQueryTimeoutDuration()`.
    Gets the default query timeout in seconds.
    Returns:
      The default query timeout in seconds.
    Since:
      2.6.0

  - ### getDefaultReadOnly

    public Boolean getDefaultReadOnly()
    Gets the default read-only-value.
    Returns:
      The default read-only-value.
    Since:
      2.6.0

  - ### getDefaultSchema

    public String getDefaultSchema()
    Gets the default schema.
    Returns:
      The default schema.
    Since:
      2.6.0

  - ### getDefaultTransactionIsolation

    public int getDefaultTransactionIsolation()
    Gets the default transaction isolation.
    Returns:
      The default transaction isolation.
    Since:
      2.6.0

  - ### getDisconnectionIgnoreSqlCodes

    public Collection<String> getDisconnectionIgnoreSqlCodes()
    Gets the collection of SQL State codes that are not considered fatal disconnection codes.

    This method returns the collection of SQL State codes that have been set to be ignored when determining if a `SQLException` signals a disconnection. These codes are excluded from being treated as fatal even if they match the typical disconnection criteria.

    Returns:
      a `Collection` of SQL State codes that should be ignored for disconnection checks.
    Since:
      2.13.0

  - ### getDisconnectionSqlCodes

    public Collection<String> getDisconnectionSqlCodes()
    Gets SQL State codes considered to signal fatal conditions.

    Overrides the defaults in `Utils.getDisconnectionSqlCodes()` (plus anything starting with `Utils.DISCONNECTION_SQL_CODE_PREFIX`). If this property is non-null and `isFastFailValidation()` is `true`, whenever connections created by this factory generate exceptions with SQL State codes in this list, they will be marked as "fatally disconnected" and subsequent validations will fail fast (no attempt at isValid or validation query).

    If `isFastFailValidation()` is `false` setting this property has no effect.

    Returns:
      SQL State codes overriding defaults
    Since:
      2.1

  - ### getMaxConnDuration

    public Duration getMaxConnDuration()
    Gets the Maximum connection duration.
    Returns:
      Maximum connection duration.
    Since:
      2.10.0

  - ### getMaxConnLifetimeMillis

    public long getMaxConnLifetimeMillis()
    Gets the Maximum connection lifetime in milliseconds.
    Returns:
      Maximum connection lifetime in milliseconds.
    Since:
      2.6.0

  - ### getMaxOpenPreparedStatements

    protected int getMaxOpenPreparedStatements()
    Gets the maximum number of open prepared statements.
    Returns:
      The maximum number of open prepared statements.

  - ### getPool

    public ObjectPool<PoolableConnection> getPool()
    Returns the `ObjectPool` in which `Connection`s are pooled.
    Returns:
      the connection pool

  - ### getPoolStatements

    public boolean getPoolStatements()
    Tests whether to pool statements.
    Returns:
      Whether to pool statements.
    Since:
      2.6.0.

  - ### getValidationQuery

    public String getValidationQuery()
    Gets the validation query.
    Returns:
      Validation query.
    Since:
      2.6.0

  - ### getValidationQueryTimeoutDuration

    public Duration getValidationQueryTimeoutDuration()
    Gets the query timeout in seconds.
    Returns:
      Validation query timeout in seconds.
    Since:
      2.10.0

  - ### getValidationQueryTimeoutSeconds

    @Deprecated public int getValidationQueryTimeoutSeconds()
    Deprecated.
    Use `getValidationQueryTimeoutDuration()`.
    Gets the query timeout in seconds.
    Returns:
      Validation query timeout in seconds.
    Since:
      2.6.0

  - ### initializeConnection

    protected void initializeConnection(Connection conn) throws SQLException
    Initializes the given connection with the collection of SQL statements set in `setConnectionInitSql(Collection)`.
    Parameters:
      `conn` - the connection to initialize.
    Throws:
      `SQLException` - if a database access error occurs or this method is called on a closed connection.
    See Also:
      - `setConnectionInitSql(Collection)`

  - ### isAutoCommitOnReturn

    public boolean isAutoCommitOnReturn()
    Tests whether to set auto-commit on `passivateObject(PooledObject)`.
    Returns:
      Whether to set auto-commit on `passivateObject(PooledObject)`.
    Since:
      2.6.0

  - ### isEnableAutoCommitOnReturn

    @Deprecated public boolean isEnableAutoCommitOnReturn()
    Deprecated.
    Use `isAutoCommitOnReturn()`.
    Tests whether to set auto-commit on `passivateObject(PooledObject)`.
    Returns:
      Whether to set auto-commit on `passivateObject(PooledObject)`.

  - ### isFastFailValidation

    public boolean isFastFailValidation()
    True means that validation will fail immediately for connections that have previously thrown SQLExceptions with SQL State indicating fatal disconnection errors.
    Returns:
      true if connections created by this factory will fast fail validation.
    Since:
      2.1, 2.5.0 Defaults to true, previous versions defaulted to false.
    See Also:
      - `setDisconnectionSqlCodes(Collection)`

  - ### isRollbackOnReturn

    public boolean isRollbackOnReturn()
    Tests whether to rollback on return.
    Returns:
      Whether to rollback on return.

  - ### makeObject

    public PooledObject<PoolableConnection> makeObject() throws SQLException
    Specified by:
      `makeObject` in interface `PooledObjectFactory<PoolableConnection>`
    Throws:
      `SQLException`

  - ### passivateObject

    public void passivateObject(PooledObject<PoolableConnection> p) throws SQLException
    Specified by:
      `passivateObject` in interface `PooledObjectFactory<PoolableConnection>`
    Throws:
      `SQLException`

  - ### setAutoCommitOnReturn

    public void setAutoCommitOnReturn(boolean autoCommitOnReturn)
    Sets whether to set auto-commit on `passivateObject(PooledObject)`.
    Parameters:
      `autoCommitOnReturn` - whether to set auto-commit.

  - ### setCacheState

    public void setCacheState(boolean cacheState)
    Sets the cache state to propagate in `makeObject()`.
    Parameters:
      `cacheState` - the cache state to propagate.

  - ### setClearStatementPoolOnReturn

    public void setClearStatementPoolOnReturn(boolean clearStatementPoolOnReturn)
    Sets whether the pool of statements (which was enabled with `setPoolStatements(boolean)`) should be cleared when the connection is returned to its pool. Default is false.
    Parameters:
      `clearStatementPoolOnReturn` - clear or not
    Since:
      2.8.0

  - ### setConnectionInitSql

    public void setConnectionInitSql(Collection<String> connectionInitSqls)
    Sets the SQL statements I use to initialize newly created `Connection`s. Using `null` turns off connection initialization.
    Parameters:
      `connectionInitSqls` - SQL statement to initialize `Connection`s.

  - ### setDefaultAutoCommit

    public void setDefaultAutoCommit(Boolean defaultAutoCommit)
    Sets the default "auto commit" setting for borrowed `Connection`s
    Parameters:
      `defaultAutoCommit` - the default "auto commit" setting for borrowed `Connection`s

  - ### setDefaultCatalog

    public void setDefaultCatalog(String defaultCatalog)
    Sets the default "catalog" setting for borrowed `Connection`s
    Parameters:
      `defaultCatalog` - the default "catalog" setting for borrowed `Connection`s

  - ### setDefaultQueryTimeout

    public void setDefaultQueryTimeout(Duration defaultQueryTimeoutDuration)
    Sets the query timeout Duration.
    Parameters:
      `defaultQueryTimeoutDuration` - the query timeout Duration.
    Since:
      2.10.0

  - ### setDefaultQueryTimeout

    @Deprecated public void setDefaultQueryTimeout(Integer defaultQueryTimeoutSeconds)
    Deprecated.
    Use `setDefaultQueryTimeout(Duration)`.
    Sets the query timeout in seconds.
    Parameters:
      `defaultQueryTimeoutSeconds` - the query timeout in seconds.

  - ### setDefaultReadOnly

    public void setDefaultReadOnly(Boolean defaultReadOnly)
    Sets the default "read only" setting for borrowed `Connection`s
    Parameters:
      `defaultReadOnly` - the default "read only" setting for borrowed `Connection`s

  - ### setDefaultSchema

    public void setDefaultSchema(String defaultSchema)
    Sets the default "schema" setting for borrowed `Connection`s
    Parameters:
      `defaultSchema` - the default "schema" setting for borrowed `Connection`s
    Since:
      2.5.0

  - ### setDefaultTransactionIsolation

    public void setDefaultTransactionIsolation(int defaultTransactionIsolation)
    Sets the default "Transaction Isolation" setting for borrowed `Connection`s
    Parameters:
      `defaultTransactionIsolation` - the default "Transaction Isolation" setting for returned `Connection`s

  - ### setDisconnectionIgnoreSqlCodes

    public void setDisconnectionIgnoreSqlCodes(Collection<String> disconnectionIgnoreSqlCodes)
    Sets the disconnection SQL codes to ignore.
    Parameters:
      `disconnectionIgnoreSqlCodes` - The collection of SQL State codes to be ignored.
    Throws:
      `IllegalArgumentException` - if any SQL state codes overlap with those in `disconnectionSqlCodes`.
    Since:
      2.13.0
    See Also:
      - `getDisconnectionIgnoreSqlCodes()`

  - ### setDisconnectionSqlCodes

    public void setDisconnectionSqlCodes(Collection<String> disconnectionSqlCodes)
    Sets the disconnection SQL codes.
    Parameters:
      `disconnectionSqlCodes` - The disconnection SQL codes.
    Throws:
      `IllegalArgumentException` - if any SQL state codes overlap with those in `disconnectionIgnoreSqlCodes`.
    Since:
      2.1
    See Also:
      - `getDisconnectionSqlCodes()`

  - ### setEnableAutoCommitOnReturn

    @Deprecated public void setEnableAutoCommitOnReturn(boolean autoCommitOnReturn)
    Deprecated.
    Sets whether to set auto-commit on `passivateObject(PooledObject)`.
    Parameters:
      `autoCommitOnReturn` - whether to set auto-commit.

  - ### setFastFailValidation

    public void setFastFailValidation(boolean fastFailValidation)
    Parameters:
      `fastFailValidation` - true means connections created by this factory will fast fail validation
    Since:
      2.1
    See Also:
      - `isFastFailValidation()`

  - ### setMaxConn

    public void setMaxConn(Duration maxConnDuration)
    Sets the maximum lifetime in milliseconds of a connection after which the connection will always fail activation, passivation and validation. A value of zero or less indicates an infinite lifetime. The default value is -1.
    Parameters:
      `maxConnDuration` - The maximum lifetime in milliseconds.
    Since:
      2.10.0

  - ### setMaxConnLifetimeMillis

    @Deprecated public void setMaxConnLifetimeMillis(long maxConnLifetimeMillis)
    Deprecated.
    Use `setMaxConn(Duration)`.
    Sets the maximum lifetime in milliseconds of a connection after which the connection will always fail activation, passivation and validation. A value of zero or less indicates an infinite lifetime. The default value is -1.
    Parameters:
      `maxConnLifetimeMillis` - The maximum lifetime in milliseconds.

  - ### setMaxOpenPreparedStatements

    public void setMaxOpenPreparedStatements(int maxOpenPreparedStatements)
    Sets the maximum number of open prepared statements.
    Parameters:
      `maxOpenPreparedStatements` - The maximum number of open prepared statements.

  - ### setMaxOpenPrepatedStatements

    @Deprecated public void setMaxOpenPrepatedStatements(int maxOpenPreparedStatements)
    Deprecated.
    Use `setMaxOpenPreparedStatements(int)`.
    Deprecated due to typo in method name.
    Parameters:
      `maxOpenPreparedStatements` - The maximum number of open prepared statements.

  - ### setPool

    public void setPool(ObjectPool<PoolableConnection> pool)
    Sets the `ObjectPool` in which to pool `Connection`s.
    Parameters:
      `pool` - the `ObjectPool` in which to pool those `Connection`s

  - ### setPoolStatements

    public void setPoolStatements(boolean poolStatements)
    Sets whether to pool statements.
    Parameters:
      `poolStatements` - whether to pool statements.

  - ### setRollbackOnReturn

    public void setRollbackOnReturn(boolean rollbackOnReturn)
    Sets whether to rollback on return.
    Parameters:
      `rollbackOnReturn` - whether to rollback on return.

  - ### setValidationQuery

    public void setValidationQuery(String validationQuery)
    Sets the query I use to `validate` `Connection`s. Should return at least one row. If not specified, `Connection.isValid(int)` will be used to validate connections.
    Parameters:
      `validationQuery` - a query to use to `validate` `Connection`s.

  - ### setValidationQueryTimeout

    public void setValidationQueryTimeout(Duration validationQueryTimeoutDuration)
    Sets the validation query timeout, the amount of time, that connection validation will wait for a response from the database when executing a validation query. Use a value less than or equal to 0 for no timeout.
    Parameters:
      `validationQueryTimeoutDuration` - new validation query timeout duration.
    Since:
      2.10.0

  - ### setValidationQueryTimeout

    @Deprecated public void setValidationQueryTimeout(int validationQueryTimeoutSeconds)
    Deprecated.
    `setValidationQueryTimeout(Duration)`.
    Sets the validation query timeout, the amount of time, in seconds, that connection validation will wait for a response from the database when executing a validation query. Use a value less than or equal to 0 for no timeout.
    Parameters:
      `validationQueryTimeoutSeconds` - new validation query timeout value in seconds

  - ### validateConnection

    public void validateConnection(PoolableConnection conn) throws SQLException
    Validates the given connection if it is open.
    Parameters:
      `conn` - the connection to validate.
    Throws:
      `SQLException` - if the connection is closed or validate fails.

  - ### validateObject

    public boolean validateObject(PooledObject<PoolableConnection> p)
    Specified by:
      `validateObject` in interface `PooledObjectFactory<PoolableConnection>`