de.fuberlin.wiwiss.d2rq.values
Class SQLExpressionValueMaker
java.lang.Object
de.fuberlin.wiwiss.d2rq.values.SQLExpressionValueMaker
- All Implemented Interfaces:
- ValueMaker
public class SQLExpressionValueMaker
- extends Object
- implements ValueMaker
A value maker that creates its values from a SQL expression.
TODO Write unit tests
- Author:
- Richard Cyganiak (richard@cyganiak.de)
Fields inherited from interface de.fuberlin.wiwiss.d2rq.values.ValueMaker |
NULL |
SQLExpressionValueMaker
public SQLExpressionValueMaker(Expression expression)
describeSelf
public void describeSelf(NodeSetFilter c)
- Specified by:
describeSelf
in interface ValueMaker
projectionSpecs
public Set<ProjectionSpec> projectionSpecs()
- Description copied from interface:
ValueMaker
- Returns a set of all
ProjectionSpec
s containing data necessary
for this ValueSource.
- Specified by:
projectionSpecs
in interface ValueMaker
- Returns:
- a set of
ProjectionSpec
s
makeValue
public String makeValue(ResultRow row)
- Description copied from interface:
ValueMaker
- Retrieves a value from a database row according to some rule or pattern.
- Specified by:
makeValue
in interface ValueMaker
- Parameters:
row
- the database row
- Returns:
- a value created from the row
valueExpression
public Expression valueExpression(String value)
- Description copied from interface:
ValueMaker
- A SQL expression that selects only rows where this value maker
produces the specified value.
Expression.FALSE
if this
value maker is incapable of producing the value.
- Specified by:
valueExpression
in interface ValueMaker
- Parameters:
value
- A value
- Returns:
- An expression that selects rows that produce this value
renameAttributes
public ValueMaker renameAttributes(ColumnRenamer renamer)
- Specified by:
renameAttributes
in interface ValueMaker
orderSpecs
public List<OrderSpec> orderSpecs(boolean ascending)
- Specified by:
orderSpecs
in interface ValueMaker
hashCode
public int hashCode()
- Overrides:
hashCode
in class Object
equals
public boolean equals(Object other)
- Overrides:
equals
in class Object
toString
public String toString()
- Overrides:
toString
in class Object