com.ibm.websphere.rsadapter

Class GenericDataStoreHelper

  • java.lang.Object
    • com.ibm.websphere.rsadapter.GenericDataStoreHelper
  • All Implemented Interfaces:
    DataStoreHelper
    Direct Known Subclasses:
    CloudscapeDataStoreHelper, com.ibm.websphere.rsadapter.DataDirectDataStoreHelper, DB2DataStoreHelper, DerbyDataStoreHelper, InformixDataStoreHelper, MicrosoftSQLServerDataStoreHelper, OracleDataStoreHelper, ProxyDSDataStoreHelper, 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

    • Field Detail

      • customDefinedWasDefaultIsoLevel

        protected int customDefinedWasDefaultIsoLevel

      • EOLN

        protected static final java.lang.String EOLN

      • genErrorMap

        protected java.util.HashMap genErrorMap
        A list of default exception mappings for a GenericDataStoreHelper.

      • tranErrorList

        protected java.util.List tranErrorList

      • defaultQueryTimeout

        protected int defaultQueryTimeout
        Default query timeout configured on the data source.
        Since:
        F010627, 500009

    • 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)

        The application server invokes this method to determine whether or not the specified error indicates a duplicate key violation. The method is invoked regardless of the data source's error detection model.

        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 based on the specified AccessIntent. If the AccessIntent parameter is null, a default value is returned that is appropriate 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 - An AccessIntent
        Returns:
        A transaction isolation level appropriate for the specified AccessIntent.
        Throws:
        javax.resource.ResourceException - If a transaction isolation level cannot be determined from the AccessIntent.

      • getResultSetType

        public int getResultSetType(AccessIntent intent)
                     throws javax.resource.ResourceException
        This method determines the result set type based on the specified AccessIntent. GenericDataStoreHelper always returns a value of java.sql.ResultSet.FETCH_FORWARD.
        Specified by:
        getResultSetType in interface DataStoreHelper
        Parameters:
        intent - An AccessIntent.
        Returns:
        A result set type constant defined on java.sql.ResultSet.
        Throws:
        javax.resource.ResourceException - If a result set type cannot be determined from the AccessIntent.

      • getResultSetConcurrency

        public int getResultSetConcurrency(AccessIntent intent)
                            throws javax.resource.ResourceException
        This method determines the result set concurrency based on the specified AccessIntent. GenericDataStoreHelper always returns java.sql.ResultSet.CONCUR_READ_ONLY.
        Specified by:
        getResultSetConcurrency in interface DataStoreHelper
        Parameters:
        intent - An AccessIntent.
        Returns:
        A result set concurrency constant defined on java.sql.ResultSet.
        Throws:
        javax.resource.ResourceException - If a result set concurrency cannot be determined from the AccessIntent.

      • 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 invoked when storing a CMP EntityBean if pessimistic concurrency control is activated. This method determines whether a potential lost update or deadlock scenario has occurred. If so, this method returns an appropriate message ID. This information is passed to the bean provider to provide notification that code changes are needed to avoid potential problems.

        pre-conditions

        • pessimistic concurrency control is being used
        • getAutoCommit() on the connection returns false

        Specified by:
        hasLostUpdateOrDeadLockOccurred in interface DataStoreHelper
        Parameters:
        isoLevel - the transaction isolation level used.
        loadedForUpdate - true if the CMP EntityBean was loaded for update (eg. FOR UPDATE keywords used on SELECT), otherwise false.
        Returns:
        One of the following
        1. DataStoreHelper.POTENTIAL_LOST_UPDATE
        2. DataStoreHelper.UPDATE_ON_READONLY
        3. DataStoreHelper.POTENTIAL_DEADLOCK

      • 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. WebSphere 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 to WebSphere 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
        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 by WebSphere 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 needed for the RAS subsystem.
        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 the userDefinedErrorMap data source custom property. When you configure the userDefinedErrorMap custom data source property, 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. This differs from the WAS 4.0 DataSource model where mapping by Error Code always takes precedence over mapping by SQL State.

        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 WebSphere DataStoreHelper implementations map the exception to UserDefinedException, whereas the WAS 4.0 DataSource map the exception to DuplicateKeyException.

        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.

      • getLockType

        public int getLockType(AccessIntent intent)

        This method returns a lock type constant based on the update hint value of the specified AccessIntent. The lock type is used by the persistence manager to determine which locking hints are used on a SELECT statement.

        GenericDataStoreHelper returns WSInteractionSpec.LOCKTYPE_SELECT in all cases, except for when all of the following are true:

        1. The access type of the AccessIntent is AccessIntent.ACCESS_TYPE_UPDATE.
        2. The concurrency control of the AccessIntent is AccessIntent.CONCURRENCY_CONTROL_PESSIMISTIC.
        3. The pessimistic update lock hint of the AccessIntent is either AccessIntent.PESSIMISTIC_UPDATE_LOCK_HINT_NONE or AccessIntent.PESSIMISTIC_UPDATE_LOCK_HINT_EXCLUSIVE.

        In the above case, GenericDataStoreHelper returns WSInteractionSpec.LOCKTYPE_SELECT_FOR_UPDATE.

        Specified by:
        getLockType in interface DataStoreHelper
        Parameters:
        intent - An AccessIntent
        Returns:
        the lock type constant. Valid values are defined in com.ibm.websphere.rsadapter.WSInteractionSpec:
        • LOCKTYPE_SELECT
        • LOCKTYPE_SELECT_FOR_UPDATE
        • LOCKTYPE_SELECT_FOR_UPDATE_WITH_RS
        • LOCKTYPE_SELECT_FOR_UPDATE_WITH_RR

      • calcPartitionNumber

        public short calcPartitionNumber(java.lang.String fullTableName,
                        java.util.Properties propPartKeys)
                          throws javax.resource.ResourceException
        This method allows you to calculate the partition number based on the input table name and partition key properties. This method is reserved for future use and is not currently called by WebSphere.
        Specified by:
        calcPartitionNumber in interface DataStoreHelper
        Parameters:
        fullTableName - - the fully qualified table name.
        propPartKeys - - the partition key properties
        Returns:
        a partition number.
        Throws:
        javax.resource.ResourceException - any exception which occurs during the calculation of a partition key will result in a 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 created by WebSphere 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.
        Since:
        WAS 5.0.1

      • 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. WebSphere uses this method to obtain trace information for XAExceptions to include in WebSphere trace.
        Specified by:
        getXAExceptionContents in interface DataStoreHelper
        Parameters:
        xae - the XAException.
        Returns:
        detailed information about the XAException, for inclusion in a WebSphere trace.
        Since:
        WAS 5.0.2

      • modifyXAFlag

        public int modifyXAFlag(int xaflag)

        This method is used only when the transactionBranchesLooselyCoupled custom DataSource property is set to true. 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.
        Since:
        WAS 5.0.1

      • isBatchUpdateSupportedWithAccessIntent

        public boolean isBatchUpdateSupportedWithAccessIntent(AccessIntent accessIntent)
        This method is used to determine if CMP Entity Beans can support batch updates with the given AccessIntent. There are some AccessIntents (for example, WebSphere Optimistic Concurrency Control intent) for which some databases are not always capable of determining the number of updated rows. This prevents CMP Entity Beans from being able to support batch updates. In such cases, this method must return false.

        GenericDataStoreHelper returns a value of true, indicating batch updates are always supported. If necessary, you can change this value by overriding this method.

        Specified by:
        isBatchUpdateSupportedWithAccessIntent in interface DataStoreHelper
        Parameters:
        accessIntent - AccessIntent
        Returns:
        boolean true if batching is allowed with the given AccessIntent, otherwise false.
        Since:
        WAS 5.0.2

      • 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 by WebSphere runtime 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.
        Implementation of this method is required if the "reauthentication" datasource custom property is set to true or if "enable reauthentication checkbox" is checked. Failure to do so might result in unpredictable behavior.
        This method is not only limited to user reauthentication; users can also take advantage of this method in other situations. For example:
        • altering the identity for audit purposes
        • altering the target schema
        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 that WebSphere runtime will pass java.util.Properties object which contains a property DataStoreHelper.FIRST_TIME_CALLED. The DataStoreHelper.FIRST_TIME_CALLED is set to true when the doConnectionSetupPerTransaction is called by WebSphere runtime for the first time for any WebSphere 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.lang.Object WebSphere runtime passes java.util.Properties when calling this method
        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 by WebSphere Application Server runtime before a connection handle is provided to the application. This method is called by WebSphere Application Server runtime 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 dealing with CMP, where 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 - boolean: specifies if the connection is used for a CMP request or another type of request.
        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 by WebSphere Application Server runtime immediately after a connection handle is closed by the application or implicitly by WebSphere 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 by WebSphere Application Server runtime 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 - boolean: specifies if the connection is used for a CMP request or another type of request.
        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
        The application server invokes this method at run time to get the password that the application server will use to establish a trusted connection using the DB2 TrustedContext "with authentication" option or when the application server switches a trusted connection to another identity, and the "with authentication" option is enabled. The password that is returned by this method will not be stored locally in the application server.
        Be aware that the application server will call this method to get the password for trusted context usage if the following is true:
        • You set the useTrustedContextWithAuthentication data source custom property to true.
        • You use the TrustedConnectionMapping login configuration.

        Specified by:
        getPasswordForUseWithTrustedContextWithAuthentication in interface DataStoreHelper
        Parameters:
        identityname - String: the identity of the connection to which the application server is switching and for which password is needed.
        realm - String: the realm name that is being used that can determine the identity of the user.
        Returns:
        String password that will be used when switching trusted context identity to the specified user.
        Throws:
        java.sql.SQLException

      • isTransientConnectionError

        public boolean isTransientConnectionError(java.sql.SQLException ex)
        Description copied from interface: DataStoreHelper
        This method determines whether a SQLException indicates a transient connection error. That means the current SQL operation can be retried on the existing connection, if the method returns true. Currently, implementation of this method is limited to JDBC 4.0 compliant drivers.
        Specified by:
        isTransientConnectionError in interface DataStoreHelper
        Parameters:
        ex - the SQLException to check.
        Returns:
        true if the exception indicates a transient connection error, otherwise false.
        See Also:
        SQLException

      • setConfig

        public final void setConfig(java.lang.Object config)
        For internal use only.
        Parameters:
        config -
IBM WebSphere Application ServerTM
Release 8.5