Class GenericDataStoreHelper

  • All Implemented Interfaces:
    DataStoreHelper
    Direct Known Subclasses:
    DataDirectDataStoreHelper, DB2DataStoreHelper, DerbyDataStoreHelper, InformixDataStoreHelper, MicrosoftSQLServerDataStoreHelper, MSSQLDataStoreHelper, OracleDataStoreHelper, SybaseDataStoreHelper

    public class GenericDataStoreHelper
    extends java.lang.Object
    implements DataStoreHelper
    GenericDataStoreHelper is a general DataStoreHelper implementation for databases and JDBC drivers fully compliant with SQL-99, X/OPEN, and JDBC. If you need to plug in additional DataStoreHelper functionality, you must either inherit from GenericDataStoreHelper or a subclass of GenericDataStoreHelper.
    Note: This class and its methods can not be called or referenced directly by user applications.

    SQLException mappings specific to the GenericDataStoreHelper are the following:

    Error CodeSQL StatePortableSQLException subclass
    23505DuplicateKeyException.class
    55032StaleConnectionException.class
    08001StaleConnectionException.class
    08003StaleConnectionException.class
    40003StaleConnectionException.class
    S1000StaleConnectionException.class
    08006StaleConnectionException.class
    08S01StaleConnectionException.class
    • Constructor Detail

      • GenericDataStoreHelper

        public GenericDataStoreHelper​(java.util.Properties props)
        This GenericDataStoreHelper constructor creates a new GenericDataStoreHelper based on the DataStoreHelper properties provided. All implementations inheriting from a data store helper must supply this same list of properties to their super class by invoking the constructor of their super class with the list of properties.
        Parameters:
        props - DataStoreHelper properties.
    • Method Detail

      • isDuplicateKey

        public boolean isDuplicateKey​(java.sql.SQLException sqlX)

        Liberty does not invoke this method.

        Specified by:
        isDuplicateKey in interface DataStoreHelper
        Parameters:
        sqlX - the error.
        Returns:
        true if the error indicates a duplicate key violation, otherwise false.
      • getIsolationLevel

        public int getIsolationLevel​(AccessIntent intent)
                              throws javax.resource.ResourceException
        This method determines the transaction isolation level to use as default for the database backend.

        For generic databases and JDBC drivers, java.sql.Connection.TRANSACTION_READ_COMMITTED is returned under all circumstances.

        Specified by:
        getIsolationLevel in interface DataStoreHelper
        Parameters:
        intent - always null in Liberty.
        Returns:
        A transaction isolation level appropriate for the specified database.
        Throws:
        javax.resource.ResourceException - If a transaction isolation level cannot be determined.
      • getResultSetType

        public int getResultSetType​(AccessIntent intent)
                             throws javax.resource.ResourceException
        This method is unused in Liberty.
        Specified by:
        getResultSetType in interface DataStoreHelper
        Throws:
        javax.resource.ResourceException
      • getResultSetConcurrency

        public int getResultSetConcurrency​(AccessIntent intent)
                                    throws javax.resource.ResourceException
        This method is unused in Liberty.
        Specified by:
        getResultSetConcurrency in interface DataStoreHelper
        Throws:
        javax.resource.ResourceException
      • isConnectionError

        public boolean isConnectionError​(java.sql.SQLException ex)
        This method determines whether a SQLException indicates a fatal connection error based on the exception map for this data store helper. You need to override this method if you provide custom exceptions that inherit from StaleConnectionException or StaleStatementException.
        Specified by:
        isConnectionError in interface DataStoreHelper
        Parameters:
        ex - the SQLException to check.
        Returns:
        true if the exception indicates a fatal connection error, otherwise false.
      • hasLostUpdateOrDeadLockOccurred

        public java.lang.String hasLostUpdateOrDeadLockOccurred​(int isoLevel,
                                                                boolean loadedForUpdate)
        This method is unused in Liberty.
        Specified by:
        hasLostUpdateOrDeadLockOccurred in interface DataStoreHelper
      • findMappingClass

        public java.lang.Class findMappingClass​(java.sql.SQLException e)

        This method locates the com.ibm.websphere.ce.cm.PortableSQLException subclass corresponding to the specified SQLException, as defined by the GenericDataStoreHelper SQLException map and user-defined SQLException map. Precedence and related details of SQLException mapping are described on the DataStoreHelper.setUserDefinedMap method.

        Overriding this method is one of three options for modifying SQLException mapping. The other two options are overriding the mapException method and invoking the setUserDefinedMap method to add a user-defined SQLException map.

        Parameters:
        e - The SQLException for which to locate a com.ibm.websphere.ce.cm.PortableSQLException subclass.
        Returns:
        The com.ibm.websphere.ce.cm.PortableSQLException subclass matching the SQLException, or null if no match was found.
      • mapException

        public java.sql.SQLException mapException​(java.sql.SQLException e)

        The application server uses this API to replace java.sql.SQLExceptions with the exceptions defined in the map if the data source's error detection model is configured to exception mapping. If configured to exception checking, then the application server consults the map to help determine the cause of the error, but does not replace the exception.

        This method maps the specified SQLException to a corresponding com.ibm.websphere.ce.cm.PortableSQLException subclass. If no corresponding com.ibm.websphere.ce.cm.PortableSQLException subclass is found, the SQLException is returned unchanged.
        Specified by:
        mapException in interface DataStoreHelper
        Parameters:
        e - a SQLException.
        Returns:
        a com.ibm.websphere.ce.cm.PortableSQLException subclass corresponding to the specified SQLException, or the unchanged SQLException if no match is found.
      • doConnectionSetup

        public void doConnectionSetup​(java.sql.Connection conn)
                               throws java.sql.SQLException

        This method configures a connection before first use. This method is invoked only when a new connection to the database is created. It is not invoked when connections are reused from the connection pool.

        GenericDataStoreHelper does not perform any connection setup.

        Specified by:
        doConnectionSetup in interface DataStoreHelper
        Parameters:
        conn - the connection to set up.
        Throws:
        java.sql.SQLException - if connection setup cannot be completed successfully.
      • doConnectionCleanup

        public boolean doConnectionCleanup​(java.sql.Connection conn)
                                    throws java.sql.SQLException

        This method is used to clean up a connection before it is returned to the connection pool for later reuse. Liberty automatically resets all standard connection properties (fields for which getters and setters are defined on java.sql.Connection). This method may be used to reset other properties proprietary to a specific JDBC driver/database and do whatever else is necessary to prepare the connection for reuse.

        A DataStoreHelper is permitted to use the provided connection to create and execute statements for the purpose of cleaning up the connection. Any statements created within the doConnectionCleanup method must be explicitly closed within the doConnectionCleanup method. The doConnectionCleanup method must never close the connection being cleaned up.

        If any standard connection properties are modified in this method, a value of true must be returned, indicating that at least one standard connection property was modified. A value of false is returned only if no standard connection properties were modified.

        GenericDataStoreHelper does not perform any connection cleanup.

        Specified by:
        doConnectionCleanup in interface DataStoreHelper
        Parameters:
        conn - the connection to attempt to cleanup.
        Returns:
        true if any standard connection property was modified, otherwise false.
        Throws:
        java.sql.SQLException - If an error occurs while cleaning up the connection.
      • doConnectionCleanupWithValidCheck

        public boolean doConnectionCleanupWithValidCheck​(java.sql.Connection conn)
                                                  throws java.sql.SQLException
        Description copied from interface: DataStoreHelper
        This method is unused in Liberty.
        Specified by:
        doConnectionCleanupWithValidCheck in interface DataStoreHelper
        Throws:
        java.sql.SQLException
      • doStatementCleanup

        public void doStatementCleanup​(java.sql.PreparedStatement stmt)
                                throws java.sql.SQLException

        This method cleans up a statement before the statement is returned to the statement cache. This method is called only for statements that are cached. It is called only if at least one of the following statement properties has changed:

        • cursorName
        • fetchDirection
        • maxFieldSize
        • maxRows
        • queryTimeout

        GenericDataStoreHelper resets all of the properties listed above.

        The following operations do not need to be included in the statement cleanup since they are automatically performed when caching statements,

        • setFetchSize(0)
        • clearParameters()
        • clearWarnings()

        A helper class implementing this method may choose to do additional cleanup for the statement. However, this should never include closing the statement, since the statement is intended to be cached.

        Specified by:
        doStatementCleanup in interface DataStoreHelper
        Parameters:
        stmt - the PreparedStatement.
        Throws:
        java.sql.SQLException - if an error occurs cleaning up the statement.
      • showLockInfo

        public java.lang.String showLockInfo​(java.util.Properties props)
                                      throws java.lang.Exception
        This method returns database lock information. It is unused in Liberty.
        Parameters:
        props - properties containing information needed to connect to the database.
        Returns:
        the lock information.
        Throws:
        java.lang.Exception - if an error occurs while collecting the lock information.
      • setUserDefinedMap

        public void setUserDefinedMap​(java.util.Map newmap)

        This method configures a user-defined SQLException map that supersedes the default SQLException mappings for the DataStoreHelper. The DataStoreHelper implementations that are provided by the application server use SQLException maps to detect connection errors that can end connections, as well as other specific types of errors. A custom DataStoreHelper can alter the default mappings by invoking this method. Do not invoke this method from a custom DataStoreHelper if you also configure identifyException for a dataSource. When you configure identifyException, the application server invokes this method to overlay the default error mappings with the error mappings that are specified in the custom property. Do not invoke this method directly from application code.

        Example usage of the setUserDefinedMap method:

            public MyCustomDataStoreHelper()
            {
               ...
               java.util.HashMap MyErrorMap = new java.util.HashMap(2);
               myErrorMap.put(new Integer(-801), MyDuplicateKeyException.class);
               myErrorMap.put(new Integer(-1015), MyStaleConnectionException.class);
               setUserDefinedMap(myErrorMap);
               ...
            }
         

        User-defined exception mapping takes priority over all other exception mapping done by a DataStoreHelper.

        For example, assume the following exception mappings are defined:

         User-defined mappings
         SQL State  S1000: UserDefinedException
        
         Default mappings
         Error Code 23505: DuplicateKeyException
         SQL State  S1000: StaleConnectionException
         

        Given the above mappings, if a SQLException is received with SQL State S1000 and Error Code 23505, the DataStoreHelper implementations map the exception to UserDefinedException.

        Additionally, mapping done by the WebSphere DataStoreHelpers does not include mapping by chained exceptions when no match is found for the original exception.

        Specified by:
        setUserDefinedMap in interface DataStoreHelper
        Parameters:
        newmap - a mapping of SQLException SQL States and Error Codes to com.ibm.websphere.ce.cm.PortableSQLException subclasses. The key for the Map must be a String (representing the SQL State) or an Integer (representing the Error Code). The value for the Map must be a subclass of com.ibm.websphere.ce.cm.PortableSQLException. User-defined subclasses are permitted, but are required to declare a public constructor accepting a SQLException as the single parameter. Void.class may also be used for the value, in which case any existing mapping for the specified SQL State or Error Code is removed.
      • calcPartitionNumber

        public short calcPartitionNumber​(java.lang.String fullTableName,
                                         java.util.Properties propPartKeys)
                                  throws javax.resource.ResourceException
        This method is unused in Liberty
        Specified by:
        calcPartitionNumber in interface DataStoreHelper
        Throws:
        javax.resource.ResourceException
      • getPrintWriter

        public java.io.PrintWriter getPrintWriter()
        This method is used to obtain the java.io.PrintWriter to use for logging when database logging is enabled (for example: WAS.database=all=enabled). By default, null is returned and a java.io.PrintWriter instance is used. You can override this method to return a different java.io.PrintWriter instance instead of the default.
        Specified by:
        getPrintWriter in interface DataStoreHelper
        Returns:
        java.io.PrintWriter.
      • getXAExceptionContents

        public java.lang.String getXAExceptionContents​(javax.transaction.xa.XAException x)
        This method provides a plug-in point for providing meaningful logging information for an XAException. The information can include details of the original exception that caused the XAException, if applicable. This method is used to obtain trace information for XAExceptions to include in trace.
        Specified by:
        getXAExceptionContents in interface DataStoreHelper
        Parameters:
        x - the XAException.
        Returns:
        detailed information about the XAException, for inclusion in trace.
      • modifyXAFlag

        public int modifyXAFlag​(int xaflag)

        This method is used only when the branch-coupling="LOOSE" resource reference extension is specified. This method modifies the given XA start flag. Some databases, such as Oracle, require a proprietary flag, such as OracleXAResource.ORATRANSLOOSE.

        GenericDataStoreHelper makes no modifications to the XA start flag.

        Specified by:
        modifyXAFlag in interface DataStoreHelper
        Parameters:
        xaflag - The XA start flag to modify.
        Returns:
        The modified XA start flag.
      • doConnectionSetupPerTransaction

        public void doConnectionSetupPerTransaction​(javax.security.auth.Subject sub,
                                                    java.lang.String user,
                                                    java.sql.Connection conn,
                                                    boolean reauthRequired,
                                                    java.lang.Object properties)
                                             throws java.sql.SQLException
        Description copied from interface: DataStoreHelper
        This method is invoked each time a connection comes out of the connection pool and only before transactions begin on that connection. This method is different from the doConnectionSetup() method which is only called when a physical connection is first created.
        Note that this method must not be used to change any of the java.sql.Connection properties.
        Note also that users might need to implement the doConnectionCleanup() method to reset the java.sql.Connection to the original state prior to calling doConnectionSetupPerTransaction
        Note also the java.util.Properties parameter which contains a property DataStoreHelper.FIRST_TIME_CALLED. The DataStoreHelper.FIRST_TIME_CALLED is set to true when the doConnectionSetupPerTransaction is called by for the first time for any connection. The DataStoreHelper.FIRST_TIME_CALLED is set to false thereafter.
        Specified by:
        doConnectionSetupPerTransaction in interface DataStoreHelper
        Parameters:
        sub - javax.security.auth.Subject for the newly requested connection. This value is null unless res-auth is set to container.
        user - java.lang.String user name of the newly requested connection. This value is specified only if the subject is null.
        conn - java.sql.Connection
        reauthRequired - boolean that indicates whether reauthentication is required on the passed connection to get the connection in sync with the subject or user name:
        • FALSE: connection is in sync with the passed subject or user name.
        • TRUE: conneciton is not in sync with the passed subject or user name. In this case, users are required to provide reauthentication implementation for the connection.
        properties - java.util.Properties
        Throws:
        java.sql.SQLException - if connection throws an exception.
      • doConnectionSetupPerGetConnection

        public boolean doConnectionSetupPerGetConnection​(java.sql.Connection conn,
                                                         boolean isCMP,
                                                         java.lang.Object props)
                                                  throws java.sql.SQLException
        Description copied from interface: DataStoreHelper
        This method is invoked before a connection handle is provided to the application. This method is called when the connection handle provided is the only handle for the associated ManagedConnection. Thus, if connection sharing occurs, this method will not be called when additional connection handles are provided to the application for the same ManagedConnection. If connection handle usage follows a get/use/close pattern, such that the ManagedConnection has only 1 active connection handle outstanding at a time, then this method will be invoked for each getConnection call made by the application.
        This method may be overridden to provide code to set up a connection before its use by the application. This is particularly useful when applications don't have direct access to connections.
        Note that The get/use/close pattern must be used by the application if this method is overridden.
        Specified by:
        doConnectionSetupPerGetConnection in interface DataStoreHelper
        Parameters:
        conn - java.sql.Connection the underlying database physical connection
        isCMP - always false in Liberty.
        props - Map<String,Object> containing additional properties. The key DataStoreHelper.SUBJECT maps to the javax.security.auth.Subject if a Subject is available.
        Returns:
        boolean false indicates no connection setup is performed by this method, true otherwise. Default is false as its a no-op.
        Throws:
        java.sql.SQLException
      • doConnectionCleanupPerCloseConnection

        public boolean doConnectionCleanupPerCloseConnection​(java.sql.Connection conn,
                                                             boolean isCMP,
                                                             java.lang.Object props)
                                                      throws java.sql.SQLException
        Description copied from interface: DataStoreHelper
        This method is invoked immediately after a connection handle is closed by the application or implicitly by the application server runtime. If you override the doConnectionSetupPerGetConnection method to perform connection setup, then you must override this method to undo all connection setup done in the doConnectionSetupPerGetConnection method.
        This method is called when the connection handle closed is the last active handle for the associated ManagedConnection. Thus, if connection sharing occurs, this method will not be called when additional connection handles are active for the same ManagedConnection. If connection handle usage follows a get/use/close pattern, such that the ManagedConnection has only 1 connection handle outstanding at a time, then this method will be invoked for each Connection.close call made by the application. If the end of a transaction (commit or rollback) occurs before Connection.close is called, then the connection handle is dissociated from the ManagedConnection and this method is not invoked.
        Note that the get/use/close pattern must be used by the application when this method is overridden.
        Specified by:
        doConnectionCleanupPerCloseConnection in interface DataStoreHelper
        Parameters:
        conn - java.sql.Connection the underlying database physical connection
        isCMP - always false in Liberty.
        props - java.lang.Object this is not used and is a place holder for future changes.
        Returns:
        boolean false indicates no connection cleanup is performed by this method, true otherwise. Default is false as its a no-op.
        Throws:
        java.sql.SQLException
      • getPasswordForUseWithTrustedContextWithAuthentication

        public java.lang.String getPasswordForUseWithTrustedContextWithAuthentication​(java.lang.String identityname,
                                                                                      java.lang.String realm)
                                                                               throws java.sql.SQLException
        Description copied from interface: DataStoreHelper
        This method is unused in Liberty.
        Specified by:
        getPasswordForUseWithTrustedContextWithAuthentication in interface DataStoreHelper
        Throws:
        java.sql.SQLException
      • setConfig

        public final void setConfig​(java.lang.Object config)
        For internal use only.
        Parameters:
        config -
      • isUnsupported

        public boolean isUnsupported​(java.sql.SQLException x)
        Description copied from interface: DataStoreHelper
        Returns true if the exception indicates an unsupported operation.
        Specified by:
        isUnsupported in interface DataStoreHelper
        Parameters:
        x - the exception.
        Returns:
        true if the exception indicates an unsupported operation.