uk.ac.ed.epcc.webapp.model.data

Class ConstIndexedSQLValue<T extends DataObject,I extends DataObject>

java.lang.Object

uk.ac.ed.epcc.webapp.model.data.ConstIndexedSQLValue<T,I>

Type Parameters:

T - Type of owning/home table.

I - Type of remote table

All Implemented Interfaces:

FilterProvider<T,IndexedReference>, GroupingSQLValue<IndexedReference>, IndexedSQLValue<T,I>, SQLValue<IndexedReference>, Targetted<IndexedReference>

public class ConstIndexedSQLValue<T extends DataObject,I extends DataObject>
extends java.lang.Object
implements IndexedSQLValue<T,I>, GroupingSQLValue<IndexedReference>

a IndexedSQLValue that resolves to a constant value. It adds the id of the reference to the SQL statement. This is therefore illegal in a GROUP BY clause so the class implements GroupingSQLValue.

See Also:

SQLGroupMapper

Constructor Summary

Constructors

Constructor and Description
ConstIndexedSQLValue(AppContext conn, java.lang.Class<T> clazz, IndexedReference<I> val)

Method Summary

Modifier and Type	Method and Description
int	add(java.lang.StringBuilder sb, boolean qualify) Add the expression to a StringBuilder
int	addGroup(java.lang.StringBuilder sb, boolean qualify) Add the group-by clause to a query.
boolean	equals(java.lang.Object obj)
DataObjectFactory<I>	getFactory() get the remote DataObjectFactory
SQLFilter<T>	getFilter(MatchCondition match, IndexedReference val) Create a SQLFilter comparing against the target value
java.lang.Class<T>	getFilterType() get the type bounds on the produced SQLFilter.
java.util.List<PatternArgument>	getGroupParameters(java.util.List<PatternArgument> list) Get the parameters for a group-by clause.
SQLExpression<java.lang.Integer>	getIDExpression() Get a Integer valued SQLExpression for the id of the referenced value.
SQLFilter<T>	getNullFilter(boolean is_null) create a SQLFilter checking if the target value is or is not null.
SQLFilter<T>	getOrderFilter(boolean descending) create a SQLFilter that orders results by the target value.
java.util.List<PatternArgument>	getParameters(java.util.List<PatternArgument> list) Add parameters for this value to a list.
SQLFilter	getRequiredFilter() Get an SQLFilter required to be added to the filter set.
SQLFilter<T>	getSQLFilter(SQLFilter<I> fil) Create a filter for the home table out of a a filter on the target object.
java.lang.Class<IndexedReference>	getTarget() Get the type of the returned object as far as it is known.
boolean	groupingIsomorphic() Is there always a one-to-one mapping between groups and values
int	hashCode()
IndexedReference<I>	makeObject(java.sql.ResultSet rs, int pos) Extract a result of the expression from a ResultSet into an object of the specified type.
java.lang.String	toString()

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface uk.ac.ed.epcc.webapp.jdbc.expr.GroupingSQLValue

checkContentsCanGroup

Constructor Detail

ConstIndexedSQLValue

public ConstIndexedSQLValue(AppContext conn,
                            java.lang.Class<T> clazz,
                            IndexedReference<I> val)

Method Detail

add

public int add(java.lang.StringBuilder sb,
               boolean qualify)

Description copied from interface: SQLValue

Add the expression to a StringBuilder

Specified by:

add in interface SQLValue<IndexedReference>

Parameters:

sb - StringBuilder to modify

qualify - boolean should fields be qualified with the table name

Returns:

number of fields added

getParameters

public java.util.List<PatternArgument> getParameters(java.util.List<PatternArgument> list)

Description copied from interface: SQLValue

Add parameters for this value to a list.

Specified by:

getParameters in interface SQLValue<IndexedReference>

Parameters:

list - to modify

Returns:

modified list of parameter objects

makeObject

public IndexedReference<I> makeObject(java.sql.ResultSet rs,
                                      int pos)
                               throws DataException

Description copied from interface: SQLValue

Extract a result of the expression from a ResultSet into an object of the specified type. Note that this method is also used to extract the result of functions over the result type.

Specified by:

makeObject in interface SQLValue<IndexedReference>

Parameters:

rs - ResultSet

Returns:

produced object

Throws:

DataException

getRequiredFilter

public SQLFilter getRequiredFilter()

Description copied from interface: SQLValue

Get an SQLFilter required to be added to the filter set. This is usually to implement a join.

Specified by:

getRequiredFilter in interface SQLValue<IndexedReference>

Returns:

null or SQLFilter

getTarget

public java.lang.Class<IndexedReference> getTarget()

Description copied from interface: Targetted

Get the type of the returned object as far as it is known. Normally this should be the erasure type corresponding to T.

Specified by:

getTarget in interface Targetted<IndexedReference>

Returns:

Class object for return type

getFilter

public SQLFilter<T> getFilter(MatchCondition match,
                              IndexedReference val)
                       throws CannotFilterException,
                              NoSQLFilterException

Description copied from interface: FilterProvider

Create a SQLFilter comparing against the target value

Specified by:

getFilter in interface FilterProvider<T extends DataObject,IndexedReference>

Returns:

SQLFilter

Throws:

CannotFilterException

NoSQLFilterException

getNullFilter

public SQLFilter<T> getNullFilter(boolean is_null)
                           throws CannotFilterException,
                                  NoSQLFilterException

Description copied from interface: FilterProvider

create a SQLFilter checking if the target value is or is not null.

Specified by:

getNullFilter in interface FilterProvider<T extends DataObject,IndexedReference>

Returns:

SQLFilter

Throws:

CannotFilterException

NoSQLFilterException

getOrderFilter

public SQLFilter<T> getOrderFilter(boolean descending)
                            throws CannotFilterException,
                                   NoSQLFilterException

Description copied from interface: FilterProvider

create a SQLFilter that orders results by the target value. This may involve joins so may not be just an OrderFilter though it will contain one.

Specified by:

getOrderFilter in interface FilterProvider<T extends DataObject,IndexedReference>

Returns:

SQLFilter

Throws:

CannotFilterException

NoSQLFilterException

getFilterType

public java.lang.Class<T> getFilterType()

Description copied from interface: FilterProvider

get the type bounds on the produced SQLFilter.

Specified by:

getFilterType in interface FilterProvider<T extends DataObject,IndexedReference>

Returns:

Class

getSQLFilter

public SQLFilter<T> getSQLFilter(SQLFilter<I> fil)
                          throws CannotFilterException

Description copied from interface: IndexedSQLValue

Create a filter for the home table out of a a filter on the target object. This adds any necessary join filters. If fil is null it only returns the necessary join filter.

Specified by:

getSQLFilter in interface IndexedSQLValue<T extends DataObject,I extends DataObject>

Returns:

SQLFilter

Throws:

CannotFilterException

getFactory

public DataObjectFactory<I> getFactory()
                                throws java.lang.Exception

Description copied from interface: IndexedSQLValue

get the remote DataObjectFactory

Specified by:

getFactory in interface IndexedSQLValue<T extends DataObject,I extends DataObject>

Returns:

DataObjectFactory

Throws:

java.lang.Exception

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

addGroup

public int addGroup(java.lang.StringBuilder sb,
                    boolean qualify)

Description copied from interface: GroupingSQLValue

Add the group-by clause to a query. Note this can be a null operation in which case it will return zero.

Specified by:

addGroup in interface GroupingSQLValue<IndexedReference>

Returns:

actual number of fields added

getGroupParameters

public java.util.List<PatternArgument> getGroupParameters(java.util.List<PatternArgument> list)

Description copied from interface: GroupingSQLValue

Get the parameters for a group-by clause.

Specified by:

getGroupParameters in interface GroupingSQLValue<IndexedReference>

Returns:

modified list

groupingIsomorphic

public final boolean groupingIsomorphic()

Description copied from interface: GroupingSQLValue

Is there always a one-to-one mapping between groups and values

Specified by:

groupingIsomorphic in interface GroupingSQLValue<IndexedReference>

Returns:

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getIDExpression

public SQLExpression<java.lang.Integer> getIDExpression()

Description copied from interface: IndexedSQLValue

Get a Integer valued SQLExpression for the id of the referenced value. This is used to provide match filters for two references.

Specified by:

getIDExpression in interface IndexedSQLValue<T extends DataObject,I extends DataObject>

Returns:

SQLExpression