org.modeshape.jcr.query.model

Class SetQuery

java.lang.Object

org.modeshape.jcr.query.model.SetQuery

All Implemented Interfaces:

Serializable, QueryCommand, SetQuery, Command, LanguageObject, Visitable

@Immutable
public class SetQuery
extends Object
implements QueryCommand, SetQuery

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

Nested Classes

Modifier and Type	Class and Description
static class	SetQuery.Operation

Constructor Summary

Constructors

Constructor and Description
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

Modifier and Type	Method and Description
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)
Column[]	getColumns() Gets the columns for this query.
QueryCommand	getLeft() Get the left-hand query.
Limit	getLimits() Get the limits associated with this query.
String	getOperation() Get the set operation for this query.
Ordering[]	getOrderings() Gets the orderings for this query.
QueryCommand	getRight() Get the right-hand query.
int	hashCode()
boolean	isAll() Return whether this set query is a 'UNION ALL' or 'INTERSECT ALL' or 'EXCEPT ALL' query.
SetQuery.Operation	operation() Get the set operation for this query.
List<? extends Ordering>	orderings() Return the orderings for this 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()

Description copied from interface: QueryCommand

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

Returns:

the list of columns; never null

getLimits

public Limit getLimits()

Description copied from interface: QueryCommand

Get the limits associated with this query.

Specified by:

getLimits in interface QueryCommand

Returns:

the limits; never null but possibly unlimited

orderings

public List<? extends Ordering> orderings()

Description copied from interface: QueryCommand

Return the orderings for this query.

Returns:

the list of orderings; never null

getLeft

public QueryCommand getLeft()

Description copied from interface: SetQuery

Get the left-hand query.

Specified by:

getLeft in interface SetQuery

Returns:

the left-hand query; never null

getRight

public QueryCommand getRight()

Description copied from interface: SetQuery

Get the right-hand query.

Specified by:

getRight in interface SetQuery

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

getOperation

public String getOperation()

Description copied from interface: SetQuery

Get the set operation for this query.

Specified by:

getOperation in interface SetQuery

Returns:

the operation; never null

isAll

public final boolean isAll()

Description copied from interface: SetQuery

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

Specified by:

isAll in interface SetQuery

Returns:

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

getOrderings

public Ordering[] getOrderings()

Description copied from interface: QueryCommand

Gets the orderings for this query.

Specified by:

getOrderings in interface QueryCommand

Returns:

an array of zero or more orderings; non-null

getColumns

public Column[] getColumns()

Description copied from interface: QueryCommand

Gets the columns for this query.

Specified by:

getColumns in interface QueryCommand

Returns:

an array of zero or more columns; non-null

toString

public String toString()

Overrides:

toString in class Object

hashCode

public int hashCode()

Overrides:

hashCode in class Object

equals

public boolean equals(Object obj)

Overrides:

equals in class Object

accept

public void accept(Visitor visitor)

Description copied from interface: Visitable

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

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.

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.

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)