er.extensions.eof.qualifiers

Class ERXExistsQualifier

java.lang.Object

com.webobjects.eocontrol.EOQualifier

er.extensions.eof.qualifiers.ERXExistsQualifier

All Implemented Interfaces:

EOKeyValueArchiving, EOQualifierEvaluation, NSCoding, Serializable, Cloneable

public class ERXExistsQualifier
extends EOQualifier
implements Cloneable, NSCoding, EOKeyValueArchiving

A qualifier that qualifies using an EXISTS clause. It will produce an SQL clause like the following: select t0.ID, t0.ATT_1, ... t0.ATT_N from FIRST_TABLE t0 where EXISTS (select t1.ID from ANOTHER_TABLE where t1.ATT_1 = ? and t1.FIRST_TABLE_ID = t0.ID)

See Also:

Serialized Form

Author:

Travis Cripps, Aaron Rosenzweig, Samuel Pelletier

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	ERXExistsQualifier.ExistsQualifierSQLGenerationSupport Implements the SQL generation for the exists qualifier.

Nested classes/interfaces inherited from class com.webobjects.eocontrol.EOQualifier

EOQualifier.Comparison, EOQualifier.ComparisonSupport, EOQualifier.QualifierVariableSubstitutionException

Nested classes/interfaces inherited from interface com.webobjects.foundation.NSCoding

NSCoding._BigDecimalSupport, NSCoding._BigIntegerSupport, NSCoding._BooleanSupport, NSCoding._ByteSupport, NSCoding._CharacterSupport, NSCoding._DateSupport, NSCoding._DoubleSupport, NSCoding._FloatSupport, NSCoding._IntegerSupport, NSCoding._LongSupport, NSCoding._NumberSupport, NSCoding._ShortSupport, NSCoding._StringSupport, NSCoding.Support

Nested classes/interfaces inherited from interface com.webobjects.eocontrol.EOKeyValueArchiving

EOKeyValueArchiving._NullValueSupport, EOKeyValueArchiving._NumberSupport, EOKeyValueArchiving._TimestampSupport, EOKeyValueArchiving.Awaking, EOKeyValueArchiving.FinishInitialization, EOKeyValueArchiving.Support

Field Summary

Fields

Modifier and Type	Field and Description
protected String	baseKeyPath Holds the key path from the base entity to the entity to which the exists clause (and qualifier) will be applied.
static String	EXISTS_ALIAS
protected EOQualifier	subqualifier Holds the subqualifier that will be applied in the exists clause.
protected boolean	usesInQualInstead
static boolean	UseSQLExistsClause
static boolean	UseSQLInClause

Fields inherited from class com.webobjects.eocontrol.EOQualifier

_CLASS, QualifierOperatorCaseInsensitiveLike, QualifierOperatorContains, QualifierOperatorEqual, QualifierOperatorGreaterThan, QualifierOperatorGreaterThanOrEqualTo, QualifierOperatorLessThan, QualifierOperatorLessThanOrEqualTo, QualifierOperatorLike, QualifierOperatorNotEqual

Fields inherited from interface com.webobjects.foundation.NSCoding

_CLASS

Fields inherited from interface com.webobjects.eocontrol.EOKeyValueArchiving

_CLASS

Constructor Summary

Constructors

Constructor and Description
ERXExistsQualifier(EOQualifier subqualifier) Public single argument constructor.
ERXExistsQualifier(EOQualifier subqualifier, String baseKeyPath) Public two argument constructor.
ERXExistsQualifier(EOQualifier subqualifier, String baseKeyPath, boolean usesInQualInstead) Public three argument constructor.

Method Summary

Modifier and Type	Method and Description
void	addQualifierKeysToSet(NSMutableSet aSet) Only used with qualifier keys which are not supported in this qualifier at this time.
String	baseKeyPath() Gets the key path from the base base entity to the entity to which the exists clause (and qualifier) will be applied.
Class	classForCoder()
Object	clone() Implementation of the Clonable interface.
static Object	decodeObject(NSCoder coder)
static Object	decodeWithKeyValueUnarchiver(EOKeyValueUnarchiver unarchiver)
void	encodeWithCoder(NSCoder coder)
void	encodeWithKeyValueArchiver(EOKeyValueArchiver archiver)
boolean	evaluateWithObject(Object object)
EOQualifier	qualifierWithBindings(NSDictionary someBindings, boolean requiresAll) Creates another qualifier after replacing the values of the bindings.
void	setUsesInQualInstead(boolean usesInQualInstead)
EOQualifier	subqualifier() Gets the subqualifier that will be applied in the exists clause.
String	toString() Description of the qualifier.
boolean	usesInQualInstead()
void	validateKeysWithRootClassDescription(EOClassDescription aClassDescription) This qualifier does not perform validation.

Methods inherited from class com.webobjects.eocontrol.EOQualifier

_accept, _isEmpty, allQualifierKeys, allQualifierOperators, bindingKeys, filterArrayWithQualifier, filteredArrayWithQualifier, keyPathForBindingKey, operatorSelectorForSelectorNamed, operatorSelectorForString, qualifierToMatchAllValues, qualifierToMatchAnyValue, qualifierWithQualifierFormat, relationalQualifierOperators, stringForOperatorSelector

Methods inherited from class java.lang.Object

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

Field Detail

EXISTS_ALIAS

public static final String EXISTS_ALIAS

See Also:

Constant Field Values

UseSQLInClause

public static final boolean UseSQLInClause

See Also:

Constant Field Values

UseSQLExistsClause

public static final boolean UseSQLExistsClause

See Also:

Constant Field Values

usesInQualInstead

protected boolean usesInQualInstead

baseKeyPath

protected String baseKeyPath

Holds the key path from the base entity to the entity to which the exists clause (and qualifier) will be applied.

subqualifier

protected EOQualifier subqualifier

Holds the subqualifier that will be applied in the exists clause.

Constructor Detail

ERXExistsQualifier

public ERXExistsQualifier(EOQualifier subqualifier)

Public single argument constructor. Use this constructor for sub-qualification on the same table.

Parameters:

subqualifier - sub-qualifier

ERXExistsQualifier

public ERXExistsQualifier(EOQualifier subqualifier,
                          String baseKeyPath)

Public two argument constructor. Use this constructor for for building queries based on a key path to a separate entity from the current entity.

Parameters:

subqualifier - sub qualifier

baseKeyPath - to the entity to which the subqualifier will be applied. Note that this should end in a relationship rather than an attribute, e.g., the key path from an Employee might be department.division.

ERXExistsQualifier

public ERXExistsQualifier(EOQualifier subqualifier,
                          String baseKeyPath,
                          boolean usesInQualInstead)

Public three argument constructor. Use this constructor when you want to try converting the EXISTS into an IN clause

Parameters:

subqualifier - sub qualifier

baseKeyPath - to the entity to which the subqualifier will be applied. Note that this should end in a relationship rather than an attribute, e.g., the key path from an Employee might be department.division.

usesInQualInstead - when true will convert the EXISTS clause into an IN clause - to be used if it makes the query plan faster.

Method Detail

subqualifier

public EOQualifier subqualifier()

Gets the subqualifier that will be applied in the exists clause.

Returns:

the subqualifier

baseKeyPath

public String baseKeyPath()

Gets the key path from the base base entity to the entity to which the exists clause (and qualifier) will be applied.

Returns:

the key path

addQualifierKeysToSet

public void addQualifierKeysToSet(NSMutableSet aSet)

Only used with qualifier keys which are not supported in this qualifier at this time. Does nothing.

Specified by:

addQualifierKeysToSet in class EOQualifier

Parameters:

aSet - of qualifier keys

qualifierWithBindings

public EOQualifier qualifierWithBindings(NSDictionary someBindings,
                                         boolean requiresAll)

Creates another qualifier after replacing the values of the bindings. Since this qualifier does not support qualifier binding keys a clone of the qualifier is returned.

Specified by:

qualifierWithBindings in class EOQualifier

Parameters:

someBindings - some bindings

requiresAll - tells if the qualifier requires all bindings

Returns:

clone of the current qualifier.

validateKeysWithRootClassDescription

public void validateKeysWithRootClassDescription(EOClassDescription aClassDescription)

This qualifier does not perform validation. This is a no-op method.

Specified by:

validateKeysWithRootClassDescription in class EOQualifier

Parameters:

aClassDescription - to validation the qualifier keys against.

toString

public String toString()

Description of the qualifier.

Overrides:

toString in class Object

Returns:

human readable description of the qualifier

clone

public Object clone()

Implementation of the Clonable interface. Clones the current qualifier.

Overrides:

clone in class EOQualifier

Returns:

cloned qualifier

classForCoder

public Class classForCoder()

Specified by:

classForCoder in interface NSCoding

decodeObject

public static Object decodeObject(NSCoder coder)

encodeWithCoder

public void encodeWithCoder(NSCoder coder)

Specified by:

encodeWithCoder in interface NSCoding

encodeWithKeyValueArchiver

public void encodeWithKeyValueArchiver(EOKeyValueArchiver archiver)

Specified by:

encodeWithKeyValueArchiver in interface EOKeyValueArchiving

decodeWithKeyValueUnarchiver

public static Object decodeWithKeyValueUnarchiver(EOKeyValueUnarchiver unarchiver)

evaluateWithObject

public boolean evaluateWithObject(Object object)

Specified by:

evaluateWithObject in interface EOQualifierEvaluation

Overrides:

evaluateWithObject in class EOQualifier

usesInQualInstead

public boolean usesInQualInstead()

setUsesInQualInstead

public void setUsesInQualInstead(boolean usesInQualInstead)