com.heckmansoft.surjey.model.datastore
Class Datastore

java.lang.Object
  com.heckmansoft.surjey.model.datastore.Datastore

Direct Known Subclasses:

QuestionDatastore, QuestionTypeDatastore, ResponseAnswerDatastore, ResponseDatastore, SectionDatastore, SurveyDatastore

public class Datastore

extends java.lang.Object

Manages object-relational mapping for ValueObject objects.

Constructor Summary

Datastore(java.lang.String tableName, java.lang.String addTableFields)
Constructor.

Method Summary

protected boolean	executeDelete(java.lang.String id) Populate and execute the prepared delete statement.
protected boolean	executeInsert(ValueObject vo) Populate and execute the prepared insert statement.
protected boolean	executeUpdate(ValueObject vo) Populate and execute the prepared update statement.
protected ValueObject	extract(java.sql.ResultSet results) Extract an object from the given result set.
protected ValueObject	extract(java.sql.ResultSet results, ValueObject vo) Populate a given object using the given result set.
protected ValueObjectList	extractList(java.sql.ResultSet results) Extract a list of objects from a given result set.
protected ValueObject	extractSingle(java.sql.ResultSet results) Extract an object from the given result set.
ValueObjectList	findAll() Finds all objects managed in this datastore.
protected java.lang.String	generateDeleteSQL(java.lang.String whereClause) Generate an SQL delete statement.
protected java.lang.String	generateInsertSQL() Generate an SQL insert statement.
protected java.lang.String	generateSelectSQL(java.lang.String whereClause) Generate an SQL select statement.
protected java.lang.String	generateUpdateSQL(java.lang.String whereClause) Generate an SQL update statement.
protected java.util.List	getArgs(ValueObject vo) From the given object, get a list of arguments to use for constructing a query or update.
java.sql.Connection	getConnection() Get the current connection.
Transaction	getTransaction() Get the current transaction.
boolean	insert(ValueObject vo) Store an object.
boolean	insert(ValueObjectList vos) Store a list of objects.
protected void	populateStatement(java.util.List args) Populate the current prepared statement, using given args.
boolean	remove(java.lang.String id) Remove a stored object with given id.
boolean	remove(ValueObject vo) Remove a stored object.
boolean	remove(ValueObjectList vos) Remove a list of stored objects.
protected java.sql.ResultSet	selectAll() Finds all objects for current table.
protected java.sql.ResultSet	selectById(java.lang.String id) Finds a particular object by its id in the current table.
protected java.sql.ResultSet	selectWhere(java.lang.String whereClause, java.util.List args) Finds all objects in the current table matching a given set of criteria.
boolean	update(ValueObject vo) Updates a given object that has been stored previously.
boolean	update(ValueObjectList vos) Updates a list of objects that have been stored previously.

Methods inherited from class java.lang.Object

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

Constructor Detail

Datastore

public Datastore(java.lang.String tableName,
                 java.lang.String addTableFields)

Constructor. Note that this datastore assumes that fields "id" and "name" exist in the table. You can specify additional fields using the second argument to this constructor.

Parameters:

tableName - The table being serviced by this datastore.

addTableFields - A comma delimited string of additional fields.

Method Detail

getConnection

public java.sql.Connection getConnection()
                                  throws DatastoreException

Get the current connection. Obtains a new one from the DAO if there is no current connection or the current connection is closed.

Returns:

The current connection.

Throws:

DatastoreException

getTransaction

public Transaction getTransaction()
                           throws DatastoreException

Get the current transaction. If there is no current transaction, a new one is created using the current connection. If there is a current transaction, the number of users of that transaction is incremented.

Returns:

The current transaction.

Throws:

DatastoreException

findAll

public ValueObjectList findAll()
                        throws DatastoreException

Finds all objects managed in this datastore.

Returns:

A List containing the objects.

Throws:

DatastoreException

insert

public boolean insert(ValueObject vo)
               throws DatastoreException

Store an object. This should only be used for objects that have not been stored before.

Parameters:

vo - The object to be stored.

Returns:

true if insert was successful.

Throws:

DatastoreException

insert

public boolean insert(ValueObjectList vos)
               throws DatastoreException

Store a list of objects. This should only be used for objects that have not been stored before. This method is more efficient than calling insert() multiple times.

Parameters:

vos - A list of objects.

Returns:

true if objects were inserted successfully

Throws:

DatastoreException

update

public boolean update(ValueObject vo)
               throws DatastoreException

Updates a given object that has been stored previously.

Parameters:

vo - The object that has been updated.

Returns:

true if object is found and updated.

Throws:

DatastoreException

update

public boolean update(ValueObjectList vos)
               throws DatastoreException

Updates a list of objects that have been stored previously. More efficient than calling update() multiple times.

Parameters:

vos - A list of updated value objects.

Returns:

true if update was successful.

Throws:

DatastoreException

remove

public boolean remove(ValueObject vo)
               throws DatastoreException

Remove a stored object.

Parameters:

vo - Object to be removed.

Returns:

true if a matching object is found and removed

Throws:

DatastoreException

remove

public boolean remove(java.lang.String id)
               throws DatastoreException

Remove a stored object with given id.

Parameters:

id - Id of object to be removed.

Returns:

true if a matching object is found and removed

Throws:

DatastoreException

remove

public boolean remove(ValueObjectList vos)
               throws DatastoreException

Remove a list of stored objects. More efficient than calling remove() multiple times.

Parameters:

vos - A list of objects to be removed.

Returns:

true if remove was successful.

Throws:

DatastoreException

selectAll

protected java.sql.ResultSet selectAll()
                                throws DatastoreException

Finds all objects for current table.

Returns:

A result set containing the results of the query.

Throws:

DatastoreException

selectById

protected java.sql.ResultSet selectById(java.lang.String id)
                                 throws DatastoreException

Finds a particular object by its id in the current table.

Parameters:

id - the id of the object to find.

Returns:

A result set containing the results of the query.

Throws:

DatastoreException

selectWhere

protected java.sql.ResultSet selectWhere(java.lang.String whereClause,
                                         java.util.List args)
                                  throws DatastoreException

Finds all objects in the current table matching a given set of criteria.

Parameters:

whereClause - The SQL where clause to use.

args - Array of Integers or Strings, with which to populate the where clause.

Returns:

A result set containing the results of the query.

Throws:

DatastoreException

executeInsert

protected boolean executeInsert(ValueObject vo)
                         throws DatastoreException

Populate and execute the prepared insert statement.

Parameters:

vo - The value object to use to populate the insert statement.

Returns:

true if insert was successful.

Throws:

java.sql.SQLException

DatastoreException

executeUpdate

protected boolean executeUpdate(ValueObject vo)
                         throws DatastoreException

Populate and execute the prepared update statement.

Parameters:

vo - The value object to use to populate the update statement.

Returns:

true if update was successful.

Throws:

java.sql.SQLException

DatastoreException

executeDelete

protected boolean executeDelete(java.lang.String id)
                         throws DatastoreException

Populate and execute the prepared delete statement.

Parameters:

id - The id to use in populating the statement.

Returns:

true if update was successful.

Throws:

java.sql.SQLException

DatastoreException

generateSelectSQL

protected java.lang.String generateSelectSQL(java.lang.String whereClause)

Generate an SQL select statement.

Parameters:

whereClause - Optional where clause to add to statement.

Returns:

The SQL statement.

generateInsertSQL

protected java.lang.String generateInsertSQL()

Generate an SQL insert statement.

Returns:

The SQL statement.

generateUpdateSQL

protected java.lang.String generateUpdateSQL(java.lang.String whereClause)

Generate an SQL update statement.

Parameters:

whereClause - Optional where clause to add to statement.

Returns:

The SQL statement.

generateDeleteSQL

protected java.lang.String generateDeleteSQL(java.lang.String whereClause)

Generate an SQL delete statement.

Parameters:

whereClause - Optional where clause to add to statement.

Returns:

The SQL statement.

populateStatement

protected void populateStatement(java.util.List args)
                          throws DatastoreException

Populate the current prepared statement, using given args.

Parameters:

args - An array of Integers and Strings

Throws:

java.sql.SQLException

DatastoreException

extractList

protected ValueObjectList extractList(java.sql.ResultSet results)
                               throws DatastoreException

Extract a list of objects from a given result set.

Parameters:

results - The result set.

Throws:

DatastoreException

extractSingle

protected ValueObject extractSingle(java.sql.ResultSet results)
                             throws DatastoreException

Extract an object from the given result set.

Parameters:

results - The result set.

Returns:

The newly extracted object.

Throws:

DatastoreException

extract

protected ValueObject extract(java.sql.ResultSet results,
                              ValueObject vo)
                       throws DatastoreException

Populate a given object using the given result set.

Parameters:

results - The result set.

vo - An object to populate.

Returns:

The populated object.

Throws:

DatastoreException

getArgs

protected java.util.List getArgs(ValueObject vo)

From the given object, get a list of arguments to use for constructing a query or update. When subclassing, this method should be overridden and called via super.getArgs(), and the resulting list should be added to.

Parameters:

vo - Object containing data to use.

Returns:

A list of arguments.

extract

protected ValueObject extract(java.sql.ResultSet results)
                       throws DatastoreException

Extract an object from the given result set. When subclassing, this method should be overridden and called via super.extract(results,foo), where foo is a new object of the type being served by the subclass.

Parameters:

results - The result set.

Returns:

The newly extracted object.

Throws:

DatastoreException