uk.org.ogsadai.activity.relational
Class MySQLExtractPhysicalSchemaActivity

java.lang.Object
  |
  +--uk.org.ogsadai.activity.Activity
        |
        +--uk.org.ogsadai.activity.relational.MySQLExtractPhysicalSchemaActivity

public class MySQLExtractPhysicalSchemaActivity
extends Activity

An activity that retrieves physical metadata from a MySQL database and returns an XML string.

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

Author:
The OGSA-DAI Team.

Field Summary
private static java.lang.String COPYRIGHT_NOTICE
          Copyright statement
static java.lang.String JOIN_BUFFER_SIZE
          Constant
private static DAILogger LOG
          Logger object for logging in this class
static java.lang.String MAX_JOIN_SIZE
          Constant
private  java.sql.Connection mConnection
          Database connection
private  java.lang.String mCredentials
          User's credentials
private  JDBCConnectionProvider mDataResource
          Database connection manager
private  BlockWriter mOutput
          Activity output - the database schema
private  java.sql.ResultSet mTableInfo
          Table metadata
private  java.lang.String mTablePattern
          Table name pattern
 
Fields inherited from class uk.org.ogsadai.activity.Activity
mContext, mExternalInputs, mExternalOutputs, mInternalInputs, mInternalOutputs
 
Constructor Summary
MySQLExtractPhysicalSchemaActivity(org.w3c.dom.Element 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 getDatabaseName(java.sql.Connection connection)
          Get the database name for this connection.
 void initialise()
          This method should be overridden by subclasses to perform any initialisation they require before the process method invocations begin.
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.Activity
connectsTo, createOutputPipe, 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


mDataResource

private JDBCConnectionProvider mDataResource
Database connection manager


mConnection

private java.sql.Connection mConnection
Database connection


mCredentials

private java.lang.String mCredentials
User's credentials


mOutput

private BlockWriter mOutput
Activity output - the database schema


mTableInfo

private java.sql.ResultSet mTableInfo
Table metadata


mTablePattern

private java.lang.String mTablePattern
Table name pattern


MAX_JOIN_SIZE

public static final java.lang.String MAX_JOIN_SIZE
Constant

See Also:
Constant Field Values

JOIN_BUFFER_SIZE

public static final java.lang.String JOIN_BUFFER_SIZE
Constant

See Also:
Constant Field Values
Constructor Detail

MySQLExtractPhysicalSchemaActivity

public MySQLExtractPhysicalSchemaActivity(org.w3c.dom.Element element)
                                   throws ActivitySpecificationException,
                                          ActivityCreationException
Method Detail

initialise

public void initialise()
                throws ActivitySpecificationException,
                       ActivityExecutionException
Description copied from class: Activity
This method should be overridden by subclasses to perform any initialisation they require before the process method invocations begin. This might be used for setting up convenient fields to reference objects contained in the context. It shouldn't be used for opening resources. That should be done in processFirst.

Overrides:
initialise in class Activity
Throws:
ActivityExecutionException - If some system problem prevents the activity from initialising.
ActivitySpecificationException - If a problem with settings provided by a client prevents the activity from initialising.

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

getDatabaseName

private java.lang.String getDatabaseName(java.sql.Connection connection)
                                  throws java.sql.SQLException
Get the database name for this connection.

Parameters:
connection - A database connection
Returns:
name of the database
Throws:
java.sql.SQLException - If there was a problem connecting to the database