org.apache.ojb.broker.query
Class QueryByCriteria

java.lang.Object
  org.apache.ojb.broker.query.AbstractQueryImpl
      org.apache.ojb.broker.query.QueryByCriteria

All Implemented Interfaces:

Serializable, Query

Direct Known Subclasses:

QueryByMtoNCriteria, ReportQueryByCriteria

public class QueryByCriteria
extends AbstractQueryImpl

represents a search by criteria. "find all articles where article.price > 100" could be represented as: Criteria crit = new Criteria(); crit.addGreaterThan("price", new Double(100)); Query qry = new QueryByCriteria(Article.class, crit); The PersistenceBroker can retrieve Objects by Queries as follows: PersistenceBroker broker = PersistenceBrokerFactory.createPersistenceBroker(); Collection col = broker.getCollectionByQuery(qry); Creation date: (24.01.2001 21:45:46)

Version:

$Id: QueryByCriteria.java,v 1.1 2007-08-24 22:17:36 ewestfal Exp $

Author:

Thomas Mahler

See Also:

Serialized Form

Field Summary

static Criteria	CRITERIA_SELECT_ALL handy criteria that can be used to select all instances of a class.
private Criteria	m_criteria
private boolean	m_distinct
private List	m_groupby
private Criteria	m_havingCriteria
private String	m_objectProjectionAttribute
private List	m_orderby
private Map	m_pathClasses
private Collection	m_pathOuterJoins
private List	m_prefetchedRelationships

Fields inherited from class org.apache.ojb.broker.query.AbstractQueryImpl

m_baseClass, m_searchClass, serialVersionUID

Fields inherited from interface org.apache.ojb.broker.query.Query

NO_END_AT_INDEX, NO_START_AT_INDEX, NOT_SCROLLABLE, SCROLLABLE

Constructor Summary

QueryByCriteria(Class aClassToSearchFrom)
Build a Query based on a Class Object.

QueryByCriteria(Class targetClass, Criteria criteria)
Build a Query for class targetClass with criteria.

QueryByCriteria(Class targetClass, Criteria criteria, boolean distinct)
Build a Query for class targetClass with criteria.

QueryByCriteria(Class targetClass, Criteria whereCriteria, Criteria havingCriteria)
Build a Query for class targetClass with criteria.

QueryByCriteria(Class targetClass, Criteria whereCriteria, Criteria havingCriteria, boolean distinct)
Build a Query for class targetClass with criteria.

QueryByCriteria(Object anObject)
Build a Query based on anObject
all non null values are used as EqualToCriteria

QueryByCriteria(Object anObject, boolean distinct)
Build a Query based on anObject
all non null values are used as EqualToCriteria

Method Summary

void	addGroupBy(FieldHelper aField) Adds a field for groupby
void	addGroupBy(String fieldName) Adds a groupby fieldName for ReportQueries.
void	addGroupBy(String[] fieldNames) Adds an array of groupby fieldNames for ReportQueries.
void	addOrderBy(FieldHelper aField) Adds a field for orderBy
void	addOrderBy(String fieldName) Deprecated. use #addOrderByAscending(String fieldName)
void	addOrderBy(String fieldName, boolean sortAscending) Adds a field for orderBy
void	addOrderByAscending(String fieldName) Adds a field for orderBy ASCENDING
void	addOrderByDescending(String fieldName) Adds a field for orderBy DESCENDING
void	addPathClass(String aPath, Class aClass) Add a hint Class for a path.
void	addPrefetchedRelationship(String aName) add the name of aRelationship for prefetched read
private static Criteria	buildCriteria(Object anExample) Build Criteria based on example object all non null values are used as EqualToCriteria
List	getClassesForPath(String aPath) Get the a List of Class objects used as hints for a path
Criteria	getCriteria() return the criteria of the query if present or null.
List	getGroupBy() Gets the groupby for ReportQueries of all Criteria and Sub Criteria the elements are of class FieldHelper
Criteria	getHavingCriteria() return the criteria of the query if present or null.
String	getObjectProjectionAttribute()
List	getOrderBy() Answer the orderBy of all Criteria and Sub Criteria the elements are of class FieldHelper
Collection	getOuterJoinPaths() Get a Collection containing all Paths having an Outer-Joins-Setting
Map	getPathClasses() Gets the pathClasses.
List	getPrefetchedRelationships() Returns the names of Relationships to be prefetched
boolean	isDistinct() Gets the distinct.
boolean	isPathOuterJoin(String aPath) Answer true if outer join for path should be used.
void	setCriteria(Criteria criteria) Sets the criteria.
void	setDistinct(boolean distinct) Sets the distinct.
void	setHavingCriteria(Criteria havingCriteria) Sets the havingCriteria.
void	setObjectProjectionAttribute(String objectProjectionAttribute) Use this method to query some related class by object references, for example query.setObjectProjectionAttribute("ref1.ref2.ref3");
void	setObjectProjectionAttribute(String objectProjectionAttribute, Class objectProjectionClass)
void	setPathClass(String aPath, Class aClass) Set the Class for a path.
void	setPathOuterJoin(String aPath) Force outer join for the last segment of the path.
String	toString() Insert the method's description here.

Methods inherited from class org.apache.ojb.broker.query.AbstractQueryImpl

fullSize, fullSize, getBaseClass, getEndAtIndex, getExampleObject, getFetchSize, getSearchClass, getStartAtIndex, getWithExtents, setEndAtIndex, setFetchSize, setStartAtIndex, setWithExtents, usePaging

Methods inherited from class java.lang.Object

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

Field Detail

m_criteria

private Criteria m_criteria

m_distinct

private boolean m_distinct

m_pathClasses

private Map m_pathClasses

m_havingCriteria

private Criteria m_havingCriteria

m_objectProjectionAttribute

private String m_objectProjectionAttribute

m_orderby

private List m_orderby

m_groupby

private List m_groupby

m_prefetchedRelationships

private List m_prefetchedRelationships

m_pathOuterJoins

private Collection m_pathOuterJoins

CRITERIA_SELECT_ALL

public static final Criteria CRITERIA_SELECT_ALL

handy criteria that can be used to select all instances of a class.

Constructor Detail

QueryByCriteria

public QueryByCriteria(Class targetClass,
                       Criteria whereCriteria,
                       Criteria havingCriteria,
                       boolean distinct)

Build a Query for class targetClass with criteria. Criteriy may be null (will result in a query returning ALL objects from a table)

QueryByCriteria

public QueryByCriteria(Class targetClass,
                       Criteria whereCriteria,
                       Criteria havingCriteria)

Build a Query for class targetClass with criteria. Criteriy may be null (will result in a query returning ALL objects from a table)

QueryByCriteria

public QueryByCriteria(Class targetClass,
                       Criteria criteria)

Build a Query for class targetClass with criteria. Criteriy may be null (will result in a query returning ALL objects from a table)

QueryByCriteria

public QueryByCriteria(Class targetClass,
                       Criteria criteria,
                       boolean distinct)

Build a Query for class targetClass with criteria. Criteriy may be null (will result in a query returning ALL objects from a table)

QueryByCriteria

public QueryByCriteria(Object anObject,
                       boolean distinct)

Build a Query based on anObject
all non null values are used as EqualToCriteria

QueryByCriteria

public QueryByCriteria(Object anObject)

Build a Query based on anObject
all non null values are used as EqualToCriteria

QueryByCriteria

public QueryByCriteria(Class aClassToSearchFrom)

Build a Query based on a Class Object. This Query will return all instances of the given class.

Parameters:

aClassToSearchFrom - the class to search from

Method Detail

buildCriteria

private static Criteria buildCriteria(Object anExample)

Build Criteria based on example object
all non null values are used as EqualToCriteria

addPathClass

public void addPathClass(String aPath,
                         Class aClass)

Add a hint Class for a path. Used for relationships to extents.
SqlStatment will use these hint classes when resolving the path. Without these hints SqlStatment will use the base class the relationship points to ie: Article instead of CdArticle.

Parameters:

aPath - the path segment ie: allArticlesInGroup

aClass - the Class ie: CdArticle

See Also:

org.apache.ojb.broker.QueryTest#testInversePathExpression()

setPathClass

public void setPathClass(String aPath,
                         Class aClass)

Set the Class for a path. Used for relationships to extents.
SqlStatment will use this class when resolving the path. Without this hint SqlStatment will use the base class the relationship points to ie: Article instead of CdArticle. Using this method is the same as adding just one hint

Parameters:

aPath - the path segment ie: allArticlesInGroup

aClass - the Class ie: CdArticle

See Also:

org.apache.ojb.broker.QueryTest#testInversePathExpression(), addPathClass(java.lang.String, java.lang.Class)

getClassesForPath

public List getClassesForPath(String aPath)

Get the a List of Class objects used as hints for a path

Parameters:

aPath - the path segment ie: allArticlesInGroup

Returns:

a List o Class objects to be used in SqlStatment

See Also:

addPathClass(java.lang.String, java.lang.Class), org.apache.ojb.broker.QueryTest#testInversePathExpression()

isPathOuterJoin

public boolean isPathOuterJoin(String aPath)

Answer true if outer join for path should be used.

Parameters:

aPath - the path to query the outer join setting for

Returns:

true for outer join

setPathOuterJoin

public void setPathOuterJoin(String aPath)

Force outer join for the last segment of the path. ie. path = 'a.b.c' the outer join will be applied only to the relationship from B to C. if multiple segments need an outer join, setPathOuterJoin needs to be called for each segement.

Parameters:

aPath - force outer join to the last segment of this path

getCriteria

public Criteria getCriteria()

Description copied from interface: Query

return the criteria of the query if present or null.

Specified by:

getCriteria in interface Query

Overrides:

getCriteria in class AbstractQueryImpl

getHavingCriteria

public Criteria getHavingCriteria()

Description copied from interface: Query

return the criteria of the query if present or null.

Specified by:

getHavingCriteria in interface Query

Overrides:

getHavingCriteria in class AbstractQueryImpl

toString

public String toString()

Insert the method's description here. Creation date: (07.02.2001 22:01:55)

Overrides:

toString in class Object

Returns:

java.lang.String

isDistinct

public boolean isDistinct()

Gets the distinct.

Specified by:

isDistinct in interface Query

Overrides:

isDistinct in class AbstractQueryImpl

Returns:

Returns a boolean

setDistinct

public void setDistinct(boolean distinct)

Sets the distinct.

Parameters:

distinct - The distinct to set

getPathClasses

public Map getPathClasses()

Gets the pathClasses. A Map containing hints about what Class to be used for what path segment

Returns:

Returns a Map

setCriteria

public void setCriteria(Criteria criteria)

Sets the criteria.

Parameters:

criteria - The criteria to set

setHavingCriteria

public void setHavingCriteria(Criteria havingCriteria)

Sets the havingCriteria.

Parameters:

havingCriteria - The havingCriteria to set

addGroupBy

public void addGroupBy(String fieldName)

Adds a groupby fieldName for ReportQueries.

Parameters:

fieldName - The groupby to set

addGroupBy

public void addGroupBy(FieldHelper aField)

Adds a field for groupby

Parameters:

aField -

addGroupBy

public void addGroupBy(String[] fieldNames)

Adds an array of groupby fieldNames for ReportQueries.

Parameters:

fieldNames - The groupby to set

getGroupBy

public List getGroupBy()

Description copied from interface: Query

Gets the groupby for ReportQueries of all Criteria and Sub Criteria the elements are of class FieldHelper

Specified by:

getGroupBy in interface Query

Overrides:

getGroupBy in class AbstractQueryImpl

Returns:

List of FieldHelper

See Also:

Query.getGroupBy()

addOrderBy

public void addOrderBy(String fieldName,
                       boolean sortAscending)

Adds a field for orderBy

Parameters:

fieldName - The field name to be used

sortAscending - true for ASCENDING, false for DESCENDING

addOrderBy

public void addOrderBy(String fieldName)

Deprecated. use #addOrderByAscending(String fieldName)

Adds a field for orderBy, order is ASCENDING

Parameters:

fieldName - The field name to be used

addOrderBy

public void addOrderBy(FieldHelper aField)

Adds a field for orderBy

Parameters:

aField -

addOrderByAscending

public void addOrderByAscending(String fieldName)

Adds a field for orderBy ASCENDING

Parameters:

fieldName - The field name to be used

addOrderByDescending

public void addOrderByDescending(String fieldName)

Adds a field for orderBy DESCENDING

Parameters:

fieldName - The field name to be used

getOrderBy

public List getOrderBy()

Description copied from interface: Query

Answer the orderBy of all Criteria and Sub Criteria the elements are of class FieldHelper

Specified by:

getOrderBy in interface Query

Overrides:

getOrderBy in class AbstractQueryImpl

Returns:

List of FieldHelper

See Also:

Query.getOrderBy()

addPrefetchedRelationship

public void addPrefetchedRelationship(String aName)

add the name of aRelationship for prefetched read

getPrefetchedRelationships

public List getPrefetchedRelationships()

Description copied from interface: Query

Returns the names of Relationships to be prefetched

Specified by:

getPrefetchedRelationships in interface Query

Overrides:

getPrefetchedRelationships in class AbstractQueryImpl

Returns:

List of Strings

getOuterJoinPaths

public Collection getOuterJoinPaths()

Get a Collection containing all Paths having an Outer-Joins-Setting

Returns:

a Collection containing the Paths (Strings)

getObjectProjectionAttribute

public String getObjectProjectionAttribute()

setObjectProjectionAttribute

public void setObjectProjectionAttribute(String objectProjectionAttribute)

Use this method to query some related class by object references, for example query.setObjectProjectionAttribute("ref1.ref2.ref3");

setObjectProjectionAttribute

public void setObjectProjectionAttribute(String objectProjectionAttribute,
                                         Class objectProjectionClass)