org.datanucleus.store.rdbms.sql.method

Class MapValueMethod

java.lang.Object

org.datanucleus.store.rdbms.sql.method.MapValueMethod

All Implemented Interfaces:

SQLMethod

public class MapValueMethod
extends Object
implements SQLMethod

Method for evaluating VALUE({mapExpr}). Returns an ObjectExpression representing the value mapping.

Constructor Summary

Constructors

Constructor and Description
MapValueMethod()

Method Summary

Modifier and Type	Method and Description
protected SQLExpression	getAsJoin(SQLStatement stmt, MapExpression mapExpr) Implementation of VALUE(map) using a join to the table representing the map, and returning the value.
protected SQLExpression	getAsSubquery(SQLStatement stmt, MapExpression mapExpr) Implementation of VALUE(map) using a subquery on the table representing the map, returning the value.
SQLExpression	getExpression(SQLStatement stmt, SQLExpression expr, List<SQLExpression> args) Return the expression for this SQL function.

Methods inherited from class java.lang.Object

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

Constructor Detail

MapValueMethod

public MapValueMethod()

Method Detail

getExpression

public SQLExpression getExpression(SQLStatement stmt,
                                   SQLExpression expr,
                                   List<SQLExpression> args)

Description copied from interface: SQLMethod

Return the expression for this SQL function.

Specified by:

getExpression in interface SQLMethod

Parameters:

stmt - SQLStatement that this expression is for

expr - The expression that it is invoked on

args - Arguments passed in

Returns:

The SQL expression using the SQL function

getAsJoin

protected SQLExpression getAsJoin(SQLStatement stmt,
                                  MapExpression mapExpr)

Implementation of VALUE(map) using a join to the table representing the map, and returning the value.

Parameters:

stmt - SQLStatement

mapExpr - The map expression

Returns:

The value expression

getAsSubquery

protected SQLExpression getAsSubquery(SQLStatement stmt,
                                      MapExpression mapExpr)

Implementation of VALUE(map) using a subquery on the table representing the map, returning the value.

Parameters:

stmt - SQLStatement

mapExpr - The map expression

Returns:

The value expression