edu.indiana.dde.mylead.dai
Class MyLeadQryAttrDefImpl

java.lang.Object
  extended by uk.org.ogsadai.engine.Activity
      extended by uk.org.ogsadai.activity.sql.SQLActivity
          extended by edu.indiana.dde.mylead.dai.MyLeadActivity
              extended by edu.indiana.dde.mylead.dai.MyLeadQryAttrDefImpl

public class MyLeadQryAttrDefImpl
extends MyLeadActivity

Handles Elements from a Grid Data Service Document.


Nested Class Summary
 
Nested classes/interfaces inherited from class uk.org.ogsadai.activity.sql.SQLActivity
uk.org.ogsadai.activity.sql.SQLActivity.ParameterInput, uk.org.ogsadai.activity.sql.SQLActivity.StreamInput, uk.org.ogsadai.activity.sql.SQLActivity.ValueInput
 
Field Summary
 
Fields inherited from class edu.indiana.dde.mylead.dai.MyLeadActivity
AUTHORITY_ADDATTR, AUTHORITY_CREATE, AUTHORITY_DEL_REPLICA, AUTHORITY_DEL_USER, AUTHORITY_DELETEATTR, AUTHORITY_UPDATE, mActivityName, mDn, mTimingPnt, MYLEAD_DB, MYLEAD_WRITER_REPLICA, MYLEAD_WRITER_TBL, startTime
 
Fields inherited from class uk.org.ogsadai.activity.sql.SQLActivity
CREATE_DATABASE, DROP_DATABASE, EXPRESSION, mAllInput, mConnection, mConnectionManager, mCredentials, mExpression, mExpressionInput, mInputStreams, mIsTransaction, mNameToInput, mOpenConnection, mOutput, mStatement, RESULT_STREAM, SQL_PARAMETERS, STORED_PROCEDURE, WEB_ROW_SET_STREAM
 
Fields inherited from class uk.org.ogsadai.engine.Activity
mContext, mExternalInputs, mExternalOutputs, mInternalInputs, mInternalOutputs
 
Constructor Summary
MyLeadQryAttrDefImpl(org.w3c.dom.Element element)
          Constructor
 
Method Summary
protected  boolean getResult()
          This method does the actual processing of the attribute definition query.
 void processBlock()
          This method will return the output on the outputStream.
 
Methods inherited from class edu.indiana.dde.mylead.dai.MyLeadActivity
checkAuthorization, dumpLog, endProcessing, finalize, getObjectId, getParameter, getWhiteboardId, markTime, queryTimestamp, startProcessing
 
Methods inherited from class uk.org.ogsadai.activity.sql.SQLActivity
initialise, loadNextExpression, parseCommand, parseResultStream, parseSQLParameters, prepareStatement, setupInputStreamNames
 
Methods inherited from class uk.org.ogsadai.engine.Activity
cleanUp, connectsTo, getActivityConfiguration, getName, getObservableStatus, getProperties, getStatus, hasActivityConfiguration, hasProperties, processFirst, setCompleted, setError
 
Methods inherited from class java.lang.Object
clone, equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

MyLeadQryAttrDefImpl

public MyLeadQryAttrDefImpl(org.w3c.dom.Element element)
                     throws uk.org.ogsadai.common.exception.engine.activity.ActivityUserException,
                            uk.org.ogsadai.common.exception.engine.activity.ActivitySystemException
Constructor

Parameters:
element - Element containing Statement conforming to schema for this activity. It is assumed schema checks have been carried out.
Throws:
uk.org.ogsadai.common.exception.engine.activity.ActivitySystemException - If there is a problem constructing the activity due to an implementation error or OGSA-DAI confguration problem.
uk.org.ogsadai.common.exception.engine.activity.ActivityUserException - If there is a problem constructing the activity due to a user mistake such as an invalid setting.
Method Detail

getResult

protected boolean getResult()
                     throws java.sql.SQLException,
                            uk.org.ogsadai.common.exception.engine.activity.ActivitySystemException,
                            uk.org.ogsadai.common.exception.engine.activity.ActivityUserException
This method does the actual processing of the attribute definition query. If it encounters any error in executing or in the data (e.g., the user does not exist) then an OGSA-DAI ActivityUserException is thrown and the processBlock method outputs the error message returned to the user.

Overrides:
getResult in class uk.org.ogsadai.activity.sql.SQLActivity
Returns:
boolean indicating if getResult completed. Although the return value is not used in this activity's process block method, it has to return a boolean since this method returns a boolean in the SQLActivity as defined in OGSA-DAI.
Throws:
SQLException, - ActivitySystemException, ActivityUserException
java.sql.SQLException
uk.org.ogsadai.common.exception.engine.activity.ActivitySystemException
uk.org.ogsadai.common.exception.engine.activity.ActivityUserException

processBlock

public void processBlock()
This method will return the output on the outputStream. After the MyLeadQryAttrDefImpl instance has been constructed, all of the parameters have been parsed from the input perform document. OGSA-DAI will then call processBlock() until there are no more results. When this method is called, if there is not a connection, a connection will be acquired (or processing is complete). If a connection is established (either new or already existing) then getResult() will be called. The getResult() method will put the output to mOutput. Compared to other activities which may process in blocks, this activity always writes it result out as a single block. If the results are query results, the activity generally feads a deliver to stream activity. No Exceptions are thrown since they will be flagged as a status flag with the activity and the output stream will be closed On error endProcessing is called and the ERROR status is set.

Specified by:
processBlock in class uk.org.ogsadai.engine.Activity