uk.ac.ed.epcc.webapp.jdbc.expr

Class LabellerSQLValue<T,R>

java.lang.Object

uk.ac.ed.epcc.webapp.jdbc.expr.LabellerSQLValue<T,R>

Type Parameters:

T - type of nested SQLValue

R - type of returned object

All Implemented Interfaces:

GroupingSQLValue<R>, NestedSQLValue<R,T>, SQLValue<R>, Targetted<R>

public class LabellerSQLValue<T,R>
extends java.lang.Object
implements NestedSQLValue<R,T>

Constructor Summary

Constructors

Constructor and Description
LabellerSQLValue(AppContext c, Labeller<T,R> labeller, SQLValue<T> nested)

Method Summary

Modifier and Type	Method and Description
int	add(java.lang.StringBuilder sb, boolean qualify) Add the expression to a StringBuilder
SQLValue<T>	getNested()
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.
java.lang.Class<R>	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
R	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, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

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

addGroup, checkContentsCanGroup, getGroupParameters

Constructor Detail

LabellerSQLValue

public LabellerSQLValue(AppContext c,
                        Labeller<T,R> labeller,
                        SQLValue<T> nested)

Method Detail

getTarget

public java.lang.Class<R> 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<R>

Returns:

Class object for return type

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<R>

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<R>

Parameters:

list - to modify

Returns:

modified list of parameter objects

makeObject

public R makeObject(java.sql.ResultSet rs,
                    int pos)
             throws DataException,
                    java.sql.SQLException

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<R>

Parameters:

rs - ResultSet

Returns:

produced object

Throws:

DataException

java.sql.SQLException

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 NestedSQLValue<R,T>

Specified by:

getRequiredFilter in interface SQLValue<R>

Returns:

null or SQLFilter

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

getNested

public SQLValue<T> getNested()

Specified by:

getNested in interface NestedSQLValue<R,T>

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<R>

Specified by:

groupingIsomorphic in interface NestedSQLValue<R,T>

Returns: