uk.org.ogsadai.activity.sql
Class SQLStoredProcedureActivity

java.lang.Object
  |
  +--uk.org.ogsadai.activity.Activity
        |
        +--uk.org.ogsadai.activity.sql.AbstractSQLActivity
              |
              +--uk.org.ogsadai.activity.sql.AbstractParameterisedSQLActivity
                    |
                    +--uk.org.ogsadai.activity.sql.SQLStoredProcedureActivity

public class SQLStoredProcedureActivity

extends AbstractParameterisedSQLActivity

Executes a stored procedure across a JDBC connection. The output is a sequence of blocks. Each block is an object of one of the following types:

• java.sql.ResultSet
• a String containing an XML fragment of the form <resultStream updateCount="N"/>
• java.util.Map mapping the position of an output parameter (which has been registered before the stored procedure was executed) to its value

The credentials of the user should be available to obtain a connection from the JDBCConnectionProvider.

For information on this activity see the OGSA-DAI user doc: OGSA-DAI/doc/interaction/activities/relational/sqlStoredProcedure.html

Author:

The OGSA-DAI Project Team.

Field Summary

private static java.lang.String	COPYRIGHT_NOTICE Copyright statement
private static DAILogger	LOG Logger object for logging in this class
private java.sql.Connection	mConnection JDBC database connection handler
private boolean	mFinishedProcessing Indicates whether processing is complete
private boolean	mGetMoreResults Are there more results to get?
private boolean	mIsResultSet Is the current result a java.sql.ResultSet?

Fields inherited from class uk.org.ogsadai.activity.sql.AbstractParameterisedSQLActivity

mParameters

Fields inherited from class uk.org.ogsadai.activity.sql.AbstractSQLActivity

CREATE_DATABASE, DROP_DATABASE, EXPRESSION, mCredentials, mDataResource, mExpression, mInputStreamNames, mOutput, mStatement, RESULT_STREAM, SQL_OUT_PARAMETERS, SQL_PARAMETERS, STORED_PROCEDURE, WEB_ROW_SET_STREAM

Fields inherited from class uk.org.ogsadai.activity.Activity

mContext, mExternalInputs, mExternalOutputs, mInternalInputs, mInternalOutputs

Constructor Summary

SQLStoredProcedureActivity(org.w3c.dom.Element element)
Constructs an activity using the specified element.

Method Summary

protected void	cleanUp() This method can be overridden by any Activity implementations that need to free up resources in the event of an error or intermediate termination of the activity processing.
private java.lang.String	getExpression(int numParameters) Constructs the expression for calling the stored procedure
private java.lang.String	getStream(org.w3c.dom.NodeList nodelist) Gets the name of the activity's output stream.
private void	parseOutParameters(org.w3c.dom.NodeList nodelist) Parses the SQL out parameters for the stored procedure and saves these.
protected void	processBlock() Performs an iteration of the processing of an activity.
protected void	processFirst() This method is called during the first iteration of processing an activity.

Methods inherited from class uk.org.ogsadai.activity.sql.AbstractParameterisedSQLActivity

initialise, initialiseInputStreamNames, parseSQLParameters

Methods inherited from class uk.org.ogsadai.activity.sql.AbstractSQLActivity

createOutputPipe, parseExpression, parseResultStream

Methods inherited from class uk.org.ogsadai.activity.Activity

connectsTo, getActivityConfiguration, getActivityName, getCause, getName, getObservableStatus, getProperties, getSession, getStatus, hasActivityConfiguration, hasProperties, process, setActivityName, setCompleted, setError

Methods inherited from class java.lang.Object

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

Field Detail

COPYRIGHT_NOTICE

private static final java.lang.String COPYRIGHT_NOTICE

Copyright statement

See Also:

Constant Field Values

LOG

private static DAILogger LOG

Logger object for logging in this class

mConnection

private java.sql.Connection mConnection

JDBC database connection handler

mFinishedProcessing

private boolean mFinishedProcessing

Indicates whether processing is complete

mGetMoreResults

private boolean mGetMoreResults

Are there more results to get?

mIsResultSet

private boolean mIsResultSet

Is the current result a java.sql.ResultSet?

Constructor Detail

SQLStoredProcedureActivity

public SQLStoredProcedureActivity(org.w3c.dom.Element element)
                           throws ActivitySpecificationException,
                                  ActivityCreationException

Constructs an activity using the specified element.

Parameters:

element - Element to configure the activity with - from a perform document.

Throws:

ActivityCreationException - If there is a problem constructing the activity.

ActivitySpecificationException - If there is a problem constructing the activity due to an invalid setting in element.

See Also:

uk.org.ogsadai.activity

Method Detail

processFirst

protected void processFirst()

Description copied from class: Activity

This method is called during the first iteration of processing an activity. It can be overridden by subclasses to define some processing that should be done only once during the first iteration of the activity processing, for example evaluating a database query.

Overrides:

processFirst in class Activity

processBlock

protected void processBlock()

Description copied from class: Activity

Performs an iteration of the processing of an activity. This may involve reading a block of input data and writing a block of output data, or may involve some other kind of processing. When an activity is processed by the OGSA-DAI engine, this method will be invoked repeatedly until the activity either completes or stops due to an error or termination call. An implementation of this method should invoke the setCompleted method to indicate that processing is complete, or the setError method if an error occurs that will prevent the processing from completing.

Specified by:

processBlock in class Activity

cleanUp

protected void cleanUp()

Description copied from class: Activity

This method can be overridden by any Activity implementations that need to free up resources in the event of an error or intermediate termination of the activity processing.

Overrides:

cleanUp in class Activity

getExpression

private java.lang.String getExpression(int numParameters)

Constructs the expression for calling the stored procedure

Parameters:

numParameters - the number of parameters that will be passed to the procedure

Returns:

the expression string.

getStream

private java.lang.String getStream(org.w3c.dom.NodeList nodelist)

Gets the name of the activity's output stream.

Parameters:

nodelist - Elements with name attributes. First node in the list has the value of the name attribute returned.

Returns:

the name of the activity's output stream

parseOutParameters

private void parseOutParameters(org.w3c.dom.NodeList nodelist)
                         throws ActivitySpecificationException

Parses the SQL out parameters for the stored procedure and saves these.

Parameters:

nodelist - Elements with position and type attributes. Each element is assumed to declare one SQL out parameter.

Throws:

ActivitySpecificationException - If the attributes have non-integer values.