Обсуждение: Database reset connection

On Wed, 2016-11-30 at 16:48 +0530, Manoj Palhade wrote:
> Hi,
>
> I have Java class which implements the Database(Postgres) related
> functionality.
>
> The problem is if Database stopped and then restart then My this
> class throws SQLException as connection got reset(database is up and
> running).
>
> Is there any way that after Database restarted; my class
> automatically Connection to database and work as expected instead of
> throwing SQLException.
>
> Is there anyway with Properties as a parameter to
> DriverManager.getConnection().
>
> Thanks and Regards,
>
> Manoj Palhade
>

From the javdoc's:-

 isValid

boolean isValid(int timeout)
                throws SQLException

    Returns true if the connection has not been closed and is still
valid. The driver shall submit a query on the connection or use some
other mechanism that positively verifies the connection is still valid
when this method is called.

    The query submitted by the driver to validate the connection shall
be executed in the context of the current transaction.

    Parameters:
        timeout - - 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.

    Returns:
        true if the connection is valid, false otherwise 
    Throws:
        SQLException - if the value supplied for timeout is less then 0
    Since:
        1.6

    See Also:
        DatabaseMetaData.getClientInfoProperties()

On Wed, 2016-11-30 at 16:48 +0530, Manoj Palhade wrote:
> Hi,
>
> I have Java class which implements the Database(Postgres) related
> functionality.
>
> The problem is if Database stopped and then restart then My this
> class throws SQLException as connection got reset(database is up and
> running).
>
> Is there any way that after Database restarted; my class
> automatically Connection to database and work as expected instead of
> throwing SQLException.
>
> Is there anyway with Properties as a parameter to
> DriverManager.getConnection().
>
> Thanks and Regards,
>
> Manoj Palhade
>

From the javdoc's:-

 isValid

boolean isValid(int timeout)
                throws SQLException

    Returns true if the connection has not been closed and is still
valid. The driver shall submit a query on the connection or use some
other mechanism that positively verifies the connection is still valid
when this method is called.

    The query submitted by the driver to validate the connection shall
be executed in the context of the current transaction.

    Parameters:
        timeout - - 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.

    Returns:
        true if the connection is valid, false otherwise 
    Throws:
        SQLException - if the value supplied for timeout is less then 0
    Since:
        1.6

    See Also:
        DatabaseMetaData.getClientInfoProperties()

Hi,

Thanks for your quick reply.

It looks like I am using JDBC3 from the runtime exception I got

 (Caused by: java.lang.AbstractMethodError: org.postgresql.jdbc3.Jdbc3Connection.isValid(I)Z)

I guess postgresql.jdbc3 does not have any way to auto Connection to database with timer.

Thanks and Regards,

Manoj Palhade

On Wed, Nov 30, 2016 at 5:58 PM, rob stone <floriparob@gmail.com> wrote:

On Wed, 2016-11-30 at 16:48 +0530, Manoj Palhade wrote:
> Hi,
>
> I have Java class which implements the Database(Postgres) related
> functionality.
>
> The problem is if Database stopped and then restart then My this
> class throws SQLException as connection got reset(database is up and
> running).
>
> Is there any way that after Database restarted; my class
> automatically Connection to database and work as expected instead of
> throwing SQLException.
>
> Is there anyway with Properties as a parameter to
> DriverManager.getConnection().
>
> Thanks and Regards,
>
> Manoj Palhade
>

From the javdoc's:-

 isValid

boolean isValid(int timeout)
                throws SQLException

    Returns true if the connection has not been closed and is still
valid. The driver shall submit a query on the connection or use some
other mechanism that positively verifies the connection is still valid
when this method is called.

    The query submitted by the driver to validate the connection shall
be executed in the context of the current transaction.

    Parameters:
        timeout - - 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.

    Returns:
        true if the connection is valid, false otherwise 
    Throws:
        SQLException - if the value supplied for timeout is less then 0
    Since:
        1.6

    See Also:
        DatabaseMetaData.getClientInfoProperties()

Hi,

Thanks for your quick reply.

It looks like I am using JDBC3 from the runtime exception I got

 (Caused by: java.lang.AbstractMethodError: org.postgresql.jdbc3.Jdbc3Connection.isValid(I)Z)

I guess postgresql.jdbc3 does not have any way to auto Connection to database with timer.

Thanks and Regards,

Manoj Palhade

On Wed, Nov 30, 2016 at 5:58 PM, rob stone <floriparob@gmail.com> wrote:

On Wed, 2016-11-30 at 16:48 +0530, Manoj Palhade wrote:
> Hi,
>
> I have Java class which implements the Database(Postgres) related
> functionality.
>
> The problem is if Database stopped and then restart then My this
> class throws SQLException as connection got reset(database is up and
> running).
>
> Is there any way that after Database restarted; my class
> automatically Connection to database and work as expected instead of
> throwing SQLException.
>
> Is there anyway with Properties as a parameter to
> DriverManager.getConnection().
>
> Thanks and Regards,
>
> Manoj Palhade
>

From the javdoc's:-

 isValid

boolean isValid(int timeout)
                throws SQLException

    Returns true if the connection has not been closed and is still
valid. The driver shall submit a query on the connection or use some
other mechanism that positively verifies the connection is still valid
when this method is called.

    The query submitted by the driver to validate the connection shall
be executed in the context of the current transaction.

    Parameters:
        timeout - - 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.

    Returns:
        true if the connection is valid, false otherwise 
    Throws:
        SQLException - if the value supplied for timeout is less then 0
    Since:
        1.6

    See Also:
        DatabaseMetaData.getClientInfoProperties()