org.modeshape.graph.query.model
Class SetQuery

java.lang.Object
  org.modeshape.graph.query.model.SetQuery

All Implemented Interfaces:

Serializable, Command, LanguageObject, QueryCommand, Visitable

Direct Known Subclasses:

JcrSetQuery

@Immutable
public class SetQuery
extends Object
implements QueryCommand

This object acts as a Set operator on multiple queries, such as performing UNION, INTERSECT, and EXCEPT operations.

The two queries are expected to have the same number and order of columns, and the corresponding columns types must be compatible.

See Also:

Serialized Form

Nested Class Summary

static class

SetQuery.Operation

Constructor Summary

SetQuery(QueryCommand left, SetQuery.Operation operation, QueryCommand right, boolean all)
Create a set query involving the supplied left- and right-hand-side queries.

SetQuery(QueryCommand left, SetQuery.Operation operation, QueryCommand right, boolean all, List<? extends Ordering> orderings, Limit limit)
Create a set query involving the supplied left- and right-hand-side queries.

Method Summary

void	accept(Visitor visitor) Accept the supplied visitor, which should call back to the visitor to complete the double-dispatch operation.
SetQuery	adding(Ordering... orderings)
List<? extends Column>	columns() Return the columns defining the query results.
boolean	equals(Object obj)
int	hashCode()
boolean	isAll() Return whether this set query is a 'UNION ALL' or 'INTERSECT ALL' or 'EXCEPT ALL' query.
QueryCommand	left() Get the left-hand query.
Limit	limits() Get the limits associated with this query.
SetQuery.Operation	operation() Get the set operation for this query.
List<? extends Ordering>	orderings() Return the orderings for this query.
QueryCommand	right() Get the right-hand query.
String	toString()
protected static boolean	unionableColumns(List<? extends Column> left, List<? extends Column> right)
SetQuery	withLimit(int rowLimit) Create a copy of this query, but one that uses the supplied limit on the number of result rows.
SetQuery	withOffset(int offset) Create a copy of this query, but one that uses the supplied offset.

Methods inherited from class java.lang.Object

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

Constructor Detail

SetQuery

public SetQuery(QueryCommand left,
                SetQuery.Operation operation,
                QueryCommand right,
                boolean all)

Create a set query involving the supplied left- and right-hand-side queries.

Parameters:

left - the left-hand-side query being combined

operation - the set operation

right - the right-hand-side query being combined

all - true if all of the results should be included

Throws:

IllegalArgumentException - if the left-hand-side query, right-hand-side query, or operation are null

SetQuery

public SetQuery(QueryCommand left,
                SetQuery.Operation operation,
                QueryCommand right,
                boolean all,
                List<? extends Ordering> orderings,
                Limit limit)

Create a set query involving the supplied left- and right-hand-side queries.

Parameters:

left - the left-hand-side query being combined

operation - the set operation

right - the right-hand-side query being combined

all - true if all of the results should be included

orderings - the specification of the order of the result rows, or null if the results need not be ordered

limit - the limit for the result rows, or null if there are no limits

Throws:

IllegalArgumentException - if the left-hand-side query, right-hand-side query, or operation are null

Method Detail

unionableColumns

protected static boolean unionableColumns(List<? extends Column> left,
                                          List<? extends Column> right)

columns

public List<? extends Column> columns()

Return the columns defining the query results. If there are no columns, then the columns are implementation determined.

Specified by:

columns in interface QueryCommand

Returns:

the list of columns; never null

See Also:

QueryCommand.columns()

limits

public Limit limits()

Get the limits associated with this query.

Specified by:

limits in interface QueryCommand

Returns:

the limits; never null but possibly unlimited

See Also:

QueryCommand.limits()

orderings

public List<? extends Ordering> orderings()

Return the orderings for this query.

Specified by:

orderings in interface QueryCommand

Returns:

the list of orderings; never null

See Also:

QueryCommand.orderings()

left

public QueryCommand left()

Get the left-hand query.

Returns:

the left-hand query; never null

right

public QueryCommand right()

Get the right-hand query.

Returns:

the right-hand query; never null

operation

public final SetQuery.Operation operation()

Get the set operation for this query.

Returns:

the operation; never null

isAll

public final boolean isAll()

Return whether this set query is a 'UNION ALL' or 'INTERSECT ALL' or 'EXCEPT ALL' query.

Returns:

true if this is an 'ALL' query, or false otherwise

toString

public String toString()

Overrides:

toString in class Object

See Also:

Object.toString()

hashCode

public int hashCode()

Overrides:

hashCode in class Object

See Also:

Object.hashCode()

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

See Also:

Object.equals(java.lang.Object)

accept

public void accept(Visitor visitor)

Accept the supplied visitor, which should call back to the visitor to complete the double-dispatch operation.

Specified by:

accept in interface Visitable

Parameters:

visitor - the visitor; never null

See Also:

Visitable.accept(org.modeshape.graph.query.model.Visitor)

withLimit

public SetQuery withLimit(int rowLimit)

Description copied from interface: QueryCommand

Create a copy of this query, but one that uses the supplied limit on the number of result rows.

Specified by:

withLimit in interface QueryCommand

Parameters:

rowLimit - the limit that should be used; must be a positive number

Returns:

the copy of the query that uses the supplied limit; never null

withOffset

public SetQuery withOffset(int offset)

Description copied from interface: QueryCommand

Create a copy of this query, but one that uses the supplied offset.

Specified by:

withOffset in interface QueryCommand

Parameters:

offset - the limit that should be used; may not be negative

Returns:

the copy of the query that uses the supplied offset; never null

adding

public SetQuery adding(Ordering... orderings)