org.eclipse.equinox.p2.query

Class QueryUtil

java.lang.Object

org.eclipse.equinox.p2.query.QueryUtil

public class QueryUtil
extends java.lang.Object

Helper class for query related tasks.

Since:

2.0

Field Summary

Fields

Modifier and Type	Field and Description
static IQuery<IInstallableUnit>	ALL_UNITS
static java.lang.String	ANY
static IQuery<IInstallableUnit>	NO_UNITS
static java.lang.String	PROP_TYPE_CATEGORY
static java.lang.String	PROP_TYPE_GROUP
static java.lang.String	PROP_TYPE_PATCH

Constructor Summary

Constructors

Constructor and Description
QueryUtil()

Method Summary

Modifier and Type	Method and Description
static <T> IQueryable<T>	compoundQueryable(java.util.Collection<? extends IQueryable<T>> queryables) Creates a queryable that combines the given collection of input queryables
static <T> IQueryable<T>	compoundQueryable(IQueryable<T> query1, IQueryable<T> query2) Creates a queryable that combines the two provided input queryables
static <T> IQuery<T>	createCompoundQuery(java.util.Collection<? extends IQuery<? extends T>> queries, boolean and) Creates a compound query that combines the given queries.
static <T> IQuery<T>	createCompoundQuery(IQuery<? extends T> query1, IQuery<T> query2, boolean and) Creates a compound query that combines the two queries.
static IQuery<IInstallableUnit>	createIUAnyQuery() Returns a query that matches all InstallableUnit elements
static IQuery<IInstallableUnit>	createIUCategoryMemberQuery(IInstallableUnit category) Creates a new query that will return the members of the given category.
static IQuery<IInstallableUnit>	createIUCategoryQuery() Creates a query matching every IInstallableUnit that is a category.
static IQuery<IInstallableUnit>	createIUGroupQuery() Creates a query matching every IInstallableUnit that is a group.
static IQuery<IInstallableUnit>	createIUPatchQuery() Creates an IInstallableUnit that will match all patches.
static IQuery<IInstallableUnit>	createIUProductQuery() Creates an IInstallableUnit that will match all products.
static IQuery<IInstallableUnit>	createIUPropertyQuery(java.lang.String propertyName, java.lang.String propertyValue) Creates a query that searches for IInstallableUnit instances that have a property whose value matches the provided value.
static IQuery<IInstallableUnit>	createIUQuery(IVersionedId versionedId) Creates a query that will match any IInstallableUnit with the given id and version.
static IQuery<IInstallableUnit>	createIUQuery(java.lang.String id) Creates a query that will match any IInstallableUnit with the given id, regardless of version.
static IQuery<IInstallableUnit>	createIUQuery(java.lang.String id, Version version) Creates a query that will match any IInstallableUnit with the given id and version.
static IQuery<IInstallableUnit>	createIUQuery(java.lang.String id, VersionRange range) Creates a query that will match any IInstallableUnit with the given id, and whose version falls in the provided range.
static IQuery<IInstallableUnit>	createLatestIUQuery() Creates a query that returns the latest version for each unique id of an IVersionedId.
static <T extends IVersionedId> IQuery<T>	createLatestQuery(IQuery<T> query) Creates a query that returns the latest version for each unique id of an IVersionedId from the collection produced by query.
static <T> IQuery<T>	createLimitQuery(IQuery<T> query, int limit) Creates a limit query that can be used to limit the number of query results returned.
static <T> IQuery<T>	createMatchQuery(java.lang.Class<? extends T> matchingClass, IExpression matchExpression, java.lang.Object... parameters) Creates an query that will iterate over all candidates and discriminate all candidates that are not instances of matchinClass> or for which the boolean matchExpression returns false.
static <T> IQuery<T>	createMatchQuery(java.lang.Class<? extends T> matchingClass, java.lang.String matchExpression, java.lang.Object... parameters) Parses the matchExpression and creates an query that will iterate over all candidates and discriminate all candidates that are not instances of matchinClass> or for which the boolean matchExpression returns false.
static IQuery<IInstallableUnit>	createMatchQuery(IExpression matchExpression, java.lang.Object... parameters) Creates an IInstallableUnit query that will iterate over all candidates and discriminate by applying the boolean matchExpression on each candidate.
static IQuery<IInstallableUnit>	createMatchQuery(java.lang.String matchExpression, java.lang.Object... parameters) Parses the matchExpression and creates an IInstallableUnit query that will iterate over all candidates and discriminate by applying the boolean matchExpression on each candidate.
static <T> IQuery<T>	createPipeQuery(java.util.Collection<? extends IQuery<? extends T>> queries) Creates a piped query based on the provided input queries.
static <T> IQuery<T>	createPipeQuery(IQuery<? extends T> query1, IQuery<? extends T> query2) Creates a piped query based on the provided input queries.
static <T> IQuery<T>	createQuery(java.lang.Class<? extends T> matchingClass, IExpression expression, java.lang.Object... parameters) Creates a query that will limit the result to instances of the matchinClass.
static <T> IQuery<T>	createQuery(java.lang.Class<? extends T> matchingClass, java.lang.String expression, java.lang.Object... parameters) Parses the expression and creates a query that will limit the result to instances of the matchinClass.
static IQuery<IInstallableUnit>	createQuery(IExpression expression, java.lang.Object... parameters) Creates an IInstallableUnit query based on an expression that uses all candidates as input.
static IQuery<IInstallableUnit>	createQuery(java.lang.String expression, java.lang.Object... parameters) Parses the expression and creates an IInstallableUnit query.
static boolean	isCategory(IInstallableUnit iu) Test if the IInstallableUnit is a category.
static boolean	isFragment(IInstallableUnit iu) Test if the IInstallableUnit is a fragment.
static boolean	isGroup(IInstallableUnit iu) Test if the IInstallableUnit is a group.
static boolean	isPatch(IInstallableUnit iu) Test if the IInstallableUnit is a patch.
static boolean	isProduct(IInstallableUnit iu) Test if the IInstallableUnit is a product.

Methods inherited from class java.lang.Object

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

Field Detail

ALL_UNITS

public static final IQuery<IInstallableUnit> ALL_UNITS

ANY

public static final java.lang.String ANY

See Also:

Constant Field Values

NO_UNITS

public static final IQuery<IInstallableUnit> NO_UNITS

PROP_TYPE_CATEGORY

public static final java.lang.String PROP_TYPE_CATEGORY

See Also:

Constant Field Values

PROP_TYPE_GROUP

public static final java.lang.String PROP_TYPE_GROUP

See Also:

Constant Field Values

PROP_TYPE_PATCH

public static final java.lang.String PROP_TYPE_PATCH

See Also:

Constant Field Values

Constructor Detail

QueryUtil

public QueryUtil()

Method Detail

compoundQueryable

public static <T> IQueryable<T> compoundQueryable(java.util.Collection<? extends IQueryable<T>> queryables)

Creates a queryable that combines the given collection of input queryables

Parameters:

queryables - The collection of queryables to be combined

compoundQueryable

public static <T> IQueryable<T> compoundQueryable(IQueryable<T> query1,
                                                  IQueryable<T> query2)

Creates a queryable that combines the two provided input queryables

Parameters:

query1 - The first queryable

query2 - The second queryable

createCompoundQuery

public static <T> IQuery<T> createCompoundQuery(java.util.Collection<? extends IQuery<? extends T>> queries,
                                                boolean and)

Creates a compound query that combines the given queries. If all queries are candidate match queries, then the queries will be concatenated as a boolean 'and' or a boolean 'or' expression depending on the and flag. If at least one query is a full query, all queries will instead be evaluated using intersection when and is true or a union.

Parameters:

queries - The queries to perform

and - true if this query represents an intersection or a logical 'and', and false if this query represents a union or a logical 'or'.

Returns:

A compound query

createCompoundQuery

public static <T> IQuery<T> createCompoundQuery(IQuery<? extends T> query1,
                                                IQuery<T> query2,
                                                boolean and)

Creates a compound query that combines the two queries. If both queries are candidate match queries, then the queries will be concatenated as a boolean 'and' or a boolean 'or' expression depending on the and flag. If at least one query is a full query, all queries will instead be evaluated using intersection when and is true or a union.

Parameters:

query1 - the first query

query2 - the second query

and - true if this query represents an intersection or a logical 'and', and false if this query represents a union or a logical 'or'.

Returns:

A compound query

createIUAnyQuery

public static IQuery<IInstallableUnit> createIUAnyQuery()

Returns a query that matches all InstallableUnit elements

createIUCategoryMemberQuery

public static IQuery<IInstallableUnit> createIUCategoryMemberQuery(IInstallableUnit category)

Creates a new query that will return the members of the given category. If the specified IInstallableUnit is not a category, then no installable unit will satisfy the query.

Parameters:

category - The category

Returns:

A query that returns category members

createIUCategoryQuery

public static IQuery<IInstallableUnit> createIUCategoryQuery()

Creates a query matching every IInstallableUnit that is a category.

Returns:

The query that matches categories

Since:

2.0

createIUGroupQuery

public static IQuery<IInstallableUnit> createIUGroupQuery()

Creates a query matching every IInstallableUnit that is a group.

Returns:

a query that matches all groups

createIUPatchQuery

public static IQuery<IInstallableUnit> createIUPatchQuery()

Creates an IInstallableUnit that will match all patches.

Returns:

The created query

createIUProductQuery

public static IQuery<IInstallableUnit> createIUProductQuery()

Creates an IInstallableUnit that will match all products.

Returns:

The created query

Since:

2.2

createIUPropertyQuery

public static IQuery<IInstallableUnit> createIUPropertyQuery(java.lang.String propertyName,
                                                             java.lang.String propertyValue)

Creates a query that searches for IInstallableUnit instances that have a property whose value matches the provided value. If no property name is specified, then all IInstallableUnit instances are accepted.

Parameters:

propertyName - The key of the property to match or null to match all

propertyValue - The value of the property. Can be ANY to match all values except null

Returns:

The query matching properties

createIUQuery

public static IQuery<IInstallableUnit> createIUQuery(IVersionedId versionedId)

Creates a query that will match any IInstallableUnit with the given id and version.

Parameters:

versionedId - The precise id/version combination that a matching unit must have

Returns:

a query that matches IU's by id and version

createIUQuery

public static IQuery<IInstallableUnit> createIUQuery(java.lang.String id)

Creates a query that will match any IInstallableUnit with the given id, regardless of version.

Parameters:

id - The installable unit id to match, or null to match any id

Returns:

a query that matches IU's by id

createIUQuery

public static IQuery<IInstallableUnit> createIUQuery(java.lang.String id,
                                                     Version version)

Creates a query that will match any IInstallableUnit with the given id and version.

Parameters:

id - The installable unit id to match, or null to match any id

version - The precise version that a matching unit must have or null to match any version

Returns:

a query that matches IU's by id and version

createIUQuery

public static IQuery<IInstallableUnit> createIUQuery(java.lang.String id,
                                                     VersionRange range)

Creates a query that will match any IInstallableUnit with the given id, and whose version falls in the provided range.

Parameters:

id - The installable unit id to match, or null to match any id

range - The version range to match or null to match any range.

Returns:

a query that matches IU's by id and range

createLatestIUQuery

public static IQuery<IInstallableUnit> createLatestIUQuery()

Creates a query that returns the latest version for each unique id of an IVersionedId. All other elements are discarded.

Returns:

A query matching the latest version for each id.

createLatestQuery

public static <T extends IVersionedId> IQuery<T> createLatestQuery(IQuery<T> query)

Creates a query that returns the latest version for each unique id of an IVersionedId from the collection produced by query. All other elements are discarded.

Parameters:

query - The query that precedes the latest query when evaluating.

Returns:

A query matching the latest version for each id.

createLimitQuery

public static <T> IQuery<T> createLimitQuery(IQuery<T> query,
                                             int limit)

Creates a limit query that can be used to limit the number of query results returned. Once the limit is reached, the query is terminated.

Parameters:

query - The query that should be limited

limit - A positive integer denoting the limit

Returns:

A limited query

Since:

2.0

createMatchQuery

public static IQuery<IInstallableUnit> createMatchQuery(IExpression matchExpression,
                                                        java.lang.Object... parameters)

Creates an IInstallableUnit query that will iterate over all candidates and discriminate by applying the boolean matchExpression on each candidate.

Parameters:

matchExpression - The boolean expression used for filtering one candidate

parameters - Values for parameter substitution

Returns:

The created query

createMatchQuery

public static IQuery<IInstallableUnit> createMatchQuery(java.lang.String matchExpression,
                                                        java.lang.Object... parameters)

Parses the matchExpression and creates an IInstallableUnit query that will iterate over all candidates and discriminate by applying the boolean matchExpression on each candidate.

Parameters:

matchExpression - The boolean expression used for filtering one candidate

parameters - Values for parameter substitution

Returns:

The created query

createMatchQuery

public static <T> IQuery<T> createMatchQuery(java.lang.Class<? extends T> matchingClass,
                                             IExpression matchExpression,
                                             java.lang.Object... parameters)

Creates an query that will iterate over all candidates and discriminate all candidates that are not instances of matchinClass> or for which the boolean matchExpression returns false.

Parameters:

matchingClass - The class that matching candidates must be an instance of

matchExpression - The boolean expression used for filtering one candidate

parameters - Values for parameter substitution

Returns:

The created query

createMatchQuery

public static <T> IQuery<T> createMatchQuery(java.lang.Class<? extends T> matchingClass,
                                             java.lang.String matchExpression,
                                             java.lang.Object... parameters)

Parses the matchExpression and creates an query that will iterate over all candidates and discriminate all candidates that are not instances of matchinClass> or for which the boolean matchExpression returns false.

Parameters:

matchingClass - The class that matching candidates must be an instance of

matchExpression - The boolean expression used for filtering one candidate

parameters - Values for parameter substitution

Returns:

The created query

createPipeQuery

public static <T> IQuery<T> createPipeQuery(java.util.Collection<? extends IQuery<? extends T>> queries)

Creates a piped query based on the provided input queries.

A pipe is a composite query in which each sub-query is executed in succession. The results from the ith sub-query are piped as input into the i+1th sub-query. The query will short-circuit if any query returns an empty result set.

Parameters:

queries - the ordered list of queries to perform

Returns:

A query pipe

createPipeQuery

public static <T> IQuery<T> createPipeQuery(IQuery<? extends T> query1,
                                            IQuery<? extends T> query2)

Creates a piped query based on the provided input queries.

A pipe is a composite query in which each sub-query is executed in succession. The results from the ith sub-query are piped as input into the i+1th sub-query. The query will short-circuit if any query returns an empty result set.

Parameters:

query1 - the first query

query2 - the second query

Returns:

A query pipe

createQuery

public static IQuery<IInstallableUnit> createQuery(IExpression expression,
                                                   java.lang.Object... parameters)

Creates an IInstallableUnit query based on an expression that uses all candidates as input.

Parameters:

expression - The query expression

parameters - Values for parameter substitution

Returns:

The created query

createQuery

public static IQuery<IInstallableUnit> createQuery(java.lang.String expression,
                                                   java.lang.Object... parameters)

Parses the expression and creates an IInstallableUnit query. The expression is expected to use all candidates as input.

Parameters:

expression - The query expression

parameters - Values for parameter substitution

Returns:

The created query

createQuery

public static <T> IQuery<T> createQuery(java.lang.Class<? extends T> matchingClass,
                                        IExpression expression,
                                        java.lang.Object... parameters)

Creates a query that will limit the result to instances of the matchinClass. The expression is expected to use all candidates as input.

Parameters:

matchingClass - The class used as discriminator for the result

expression - The query expression

parameters - Values for parameter substitution

Returns:

The created query

createQuery

public static <T> IQuery<T> createQuery(java.lang.Class<? extends T> matchingClass,
                                        java.lang.String expression,
                                        java.lang.Object... parameters)

Parses the expression and creates a query that will limit the result to instances of the matchinClass. The expression is expected to use all candidates as input.

Parameters:

matchingClass - The class used as discriminator for the result

expression - The query expression

parameters - Values for parameter substitution

Returns:

The created query

isCategory

public static boolean isCategory(IInstallableUnit iu)

Test if the IInstallableUnit is a category.

Parameters:

iu - the element being tested.

Returns:

true if the parameter is a category.

isFragment

public static boolean isFragment(IInstallableUnit iu)

Test if the IInstallableUnit is a fragment.

Parameters:

iu - the element being tested.

Returns:

true if the parameter is a fragment.

isGroup

public static boolean isGroup(IInstallableUnit iu)

Test if the IInstallableUnit is a group.

Parameters:

iu - the element being tested.

Returns:

true if the parameter is a group.

isProduct

public static boolean isProduct(IInstallableUnit iu)

Test if the IInstallableUnit is a product.

Parameters:

iu - the element being tested.

Returns:

true if the parameter is a group.

Since:

2.2

isPatch

public static boolean isPatch(IInstallableUnit iu)

Test if the IInstallableUnit is a patch.

Parameters:

iu - the element being tested.

Returns:

true if the parameter is a patch.