nz.co.gregs.dbvolution.actions

Class DBMigrationAction<R extends DBRow>

java.lang.Object

nz.co.gregs.dbvolution.actions.DBAction

nz.co.gregs.dbvolution.actions.DBMigrationAction<R>

Type Parameters:

R - the resulting DBRow from this DBQueryInsertAction

All Implemented Interfaces:

DBExecutable

public class DBMigrationAction<R extends DBRow>
extends DBAction

Provides support for the abstract concept of migrating rows from one or more tables to another table.

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Author:

Gregory Graham

Constructor Summary

Constructors

Constructor and Description
DBMigrationAction(DBMigration<R> migration, DBRow resultRow, DBRow... examples) Creates a DBMigrate action for the row.

Method Summary

Methods

Modifier and Type	Method and Description
DBActionList	execute(DBDatabase db) Performs the DB execute and returns a list of all actions performed in the process.
protected DBActionList	getActions() Returns a DBActionList of the actions required to perform this DBAction.
protected DBActionList	getRevertDBActionList() Returns a DBActionList containing the changes required to revert the DBAction.
ArrayList<String>	getSQLStatements(DBDatabase db) Returns a list of the SQL statements that this DBAction will produce for the specified database.
DBActionList	migrate(DBDatabase database) Perform the migration

Methods inherited from class nz.co.gregs.dbvolution.actions.DBAction

getPrimaryKeySQL, getRow

Methods inherited from class java.lang.Object

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

Constructor Detail

DBMigrationAction

public DBMigrationAction(DBMigration<R> migration,
                 DBRow resultRow,
                 DBRow... examples)

Creates a DBMigrate action for the row.

Parameters:

migration - the mapping to transform the source data

resultRow - the resulting DBRow produced by the mapping

examples - extra examples used to reduce the source data set.

Method Detail

migrate

public DBActionList migrate(DBDatabase database)
                     throws SQLException

Perform the migration

Parameters:

database - the database used by this action

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Returns:

a DBActionList of the migration's effects

Throws:

SQLException - SQL Exceptions may be thrown

getSQLStatements

public ArrayList<String> getSQLStatements(DBDatabase db)

Description copied from class: DBAction

Returns a list of the SQL statements that this DBAction will produce for the specified database.

Actions happen all by themselves but when you want to know what will actually happen, use this method to get a complete list of all the SQL required.

Specified by:

getSQLStatements in class DBAction

Parameters:

db - the database that the SQL must be appropriate for.

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Returns:

the list of SQL strings that equates to this action.

execute

public DBActionList execute(DBDatabase db)
                     throws SQLException

Description copied from interface: DBExecutable

Performs the DB execute and returns a list of all actions performed in the process.

The supplied row will be changed by the action in an appropriate way, however the Action will contain an unchanged and unchangeable copy of the row for internal use.

Parameters:

db - the target database.

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Returns:

The complete list of all actions performed to complete this action on the database

Throws:

SQLException - Database operations may throw SQLExceptions

getRevertDBActionList

protected DBActionList getRevertDBActionList()

Description copied from class: DBAction

Returns a DBActionList containing the changes required to revert the DBAction.

Every action has an opposite reaction. This method supplies the actions require to revert the change enacted by the action.

Revert actions are tricky to implement correctly, so be sure to check that the revert will produce the desired result.

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Specified by:

getRevertDBActionList in class DBAction

Returns:

a list of all the actions required to revert this action in the order they need to enacted.

getActions

protected DBActionList getActions()

Description copied from class: DBAction

Returns a DBActionList of the actions required to perform this DBAction.

Actions are allowed to create sub-actions so all actions are returned as a DBActionList.

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Specified by:

getActions in class DBAction

Returns:

a DBActionList of this DBAction.