org.eclipse.stardust.engine.api.query

Class Query

java.lang.Object

org.eclipse.stardust.engine.api.query.Query

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

ActivityInstanceQuery, BusinessObjectQuery, DataQuery, DeployedModelQuery, DeployedRuntimeArtifactQuery, DocumentQuery, LogEntryQuery, PreferenceQuery, ProcessDefinitionQuery, ProcessInstanceQuery, UserGroupQuery, UserQuery, WorklistQuery

public abstract class Query
extends Object
implements Serializable

Basic functionality for creating query containers for complex queries.

A query consists of the following three optional parts:

• Filter criteria to qualify/reduce the set of data returned
• Order conditions to (partially) specify the order of the data returned.
• Evaluation policies to select strategies for evaluating the query.

Version:

$Revision$

Author:

rsauer

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
Query(FilterVerifier filterVerifyer)

Method Summary

Methods

Modifier and Type	Method and Description
FilterAndTerm	getFilter() Gets the top-level filter term.
OrderCriteria	getOrderCriteria() Gets the top-level order criteria.
EvaluationPolicy	getPolicy(Class policyClass) Extracts any set policy of the given kind.
OrderCriteria	orderBy(FilterableAttribute attribute) Orders the resulting elements by ascending values of the given attribute.
OrderCriteria	orderBy(FilterableAttribute attribute, boolean ascending) Orders the resulting elements by either ascending or descending values of the given attribute.
OrderCriteria	orderBy(OrderCriterion criterion) Adds a new order criterion.
void	removePolicy(Class policyClass) Removes any set policy of the given kind.
void	setPolicy(EvaluationPolicy policy) Sets the given policy.
String	toString()
FilterAndTerm	where(FilterCriterion filter) Adds the given filter criterion to the top-level filter term.

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

Query

public Query(FilterVerifier filterVerifyer)

Method Detail

getFilter

public final FilterAndTerm getFilter()

Gets the top-level filter term.

Returns:

The top-level AND filtert term.

See Also:

where(FilterCriterion)

where

public final FilterAndTerm where(FilterCriterion filter)
                          throws UnsupportedFilterException

Adds the given filter criterion to the top-level filter term.

Parameters:

filter - The filter criterion to be added

Returns:

The top-level AND filer-term, thus allowing for chained calls.

Throws:

UnsupportedFilterException - if the filter criterion to be added is not valid for this specific query

See Also:

getFilter()

orderBy

public final OrderCriteria orderBy(OrderCriterion criterion)

Adds a new order criterion.

Parameters:

criterion - The order criterion to add.

Returns:

The callee's order criteria, thus allowing chained calls.

See Also:

orderBy(FilterableAttribute, boolean), orderBy(FilterableAttribute)

orderBy

public final OrderCriteria orderBy(FilterableAttribute attribute)

Orders the resulting elements by ascending values of the given attribute.

Parameters:

attribute - The attribute to order by.

Returns:

The callee's order criteria, thus allowing chained calls.

See Also:

orderBy(FilterableAttribute, boolean), orderBy(OrderCriterion)

orderBy

public final OrderCriteria orderBy(FilterableAttribute attribute,
                    boolean ascending)

Orders the resulting elements by either ascending or descending values of the given attribute.

Parameters:

attribute - The attribute to order by.

ascending - Flag indicating if ordering should be performed by either ascending or descending attribute value.

Returns:

The callee's order criteria, thus allowing chained calls.

See Also:

orderBy(FilterableAttribute), orderBy(OrderCriterion)

getOrderCriteria

public final OrderCriteria getOrderCriteria()

Gets the top-level order criteria.

Returns:

The top-level order criteria.

See Also:

orderBy(FilterableAttribute), orderBy(OrderCriterion), orderBy(FilterableAttribute, boolean)

getPolicy

public final EvaluationPolicy getPolicy(Class policyClass)

Extracts any set policy of the given kind.

Parameters:

policyClass - The kind of policy to extract.

Returns:

The policy, or null if no such policy exists for the query.

See Also:

setPolicy(org.eclipse.stardust.engine.api.query.EvaluationPolicy), removePolicy(java.lang.Class)

setPolicy

public final void setPolicy(EvaluationPolicy policy)

Sets the given policy.

There always exists at most one policy per policy class. Thus an existing policy of the same class is overwritten.

Parameters:

policy - The policy to be set.

See Also:

getPolicy(java.lang.Class), removePolicy(java.lang.Class)

removePolicy

public final void removePolicy(Class policyClass)

Removes any set policy of the given kind.

Parameters:

policyClass - The kind of policy to be removed from the query.

See Also:

getPolicy(java.lang.Class), setPolicy(org.eclipse.stardust.engine.api.query.EvaluationPolicy)

toString

public String toString()

Overrides:

toString in class Object