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

Class ArrayFuncValue<F,T>

java.lang.Object

uk.ac.ed.epcc.webapp.jdbc.expr.ArrayFuncValue<F,T>

Type Parameters:

T -

All Implemented Interfaces:

SQLValue<T>, Targetted<T>

public class ArrayFuncValue<F,T>
extends java.lang.Object
implements SQLValue<T>

A SQLValue that selects one of a set of values under control of an ArrayFunc (e.g. greatest/least).

Constructor Summary

Constructors

Constructor and Description
ArrayFuncValue(java.lang.Class<F> filter_type, ArrayFunc f, java.lang.Class<T> target, SQLValue<? extends T>... e)

Method Summary

Modifier and Type	Method and Description
int	add(java.lang.StringBuilder sb, boolean qualify) Add the expression to a StringBuilder
java.util.List<PatternArgument>	getParameters(java.util.List<PatternArgument> list) Add parameters for this value to a list.
SQLFilter<F>	getRequiredFilter() Get an SQLFilter required to be added to the filter set.
java.lang.Class<T>	getTarget() Get the type of the returned object as far as it is known.
T	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

Constructor Detail

ArrayFuncValue

public ArrayFuncValue(java.lang.Class<F> filter_type,
                      ArrayFunc f,
                      java.lang.Class<T> target,
                      SQLValue<? extends T>... e)

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<T>

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<T>

Parameters:

list - to modify

Returns:

modified list of parameter objects

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

makeObject

public T 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<T>

Parameters:

rs - ResultSet

Returns:

produced object

Throws:

DataException

java.sql.SQLException

getTarget

public java.lang.Class<T> 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<T>

Returns:

Class object for return type

getRequiredFilter

public SQLFilter<F> 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<T>

Returns:

null or SQLFilter