wt.query
Class ClassAttribute

java.lang.Object
  wt.query.ClassAttribute

All Implemented Interfaces:

ColumnExpression, Expression, Externalizable, OrderByExpression, RelationalExpression, Serializable

public class ClassAttribute

extends Object

implements ColumnExpression, Externalizable

This class represents a class attribute which can be used in a SQL statement. Introspection information is used to determine the associated table and column.

When a query executes, a ClassAttribute used in the query internally references a TableExpression from that query. A single instance of ClassAttribute must only be associated to a single TableExpression. If multiple classes are used in the query or a sub-select is used, then a single instances of ClassAttribute should not be reused in different query expressions. Instead, construct multiple instances, as needed.

Supported API: true

Extendable: false

See Also:

Serialized Form

Field Summary

private boolean	advancedQueryEnabled
private String	alias
private String	attributeName
private static String	CLASSNAME
private String	columnAlias
private ColumnDescriptor	columnDescriptor
private boolean	correlated
private TableExpression	correlatedTable
static long	EXTERNALIZATION_VERSION_UID
private Class	javaType
protected static long	OLD_FORMAT_VERSION_UID
private static String	RESOURCE
(package private) static long	serialVersionUID
private Class	targetClass
private boolean	useExplicitAlias
private boolean	useViewTableAlias
private String	viewTableAlias
private Class	viewTableClass

Fields inherited from interface wt.query.ColumnExpression

ADVANCED_QUERY, ADVANCED_QUERY_ENABLED, COLUMN_ALIAS, JAVA_TYPE

Fields inherited from interface wt.query.Expression

FROM_COUNT

Fields inherited from interface wt.query.RelationalExpression

BIND_PARAMETER

Constructor Summary

ClassAttribute()


Supported API: false

ClassAttribute(Class a_targetClass, String a_attributeName)


Supported API: true

ClassAttribute(Class a_targetClass, String a_attributeName, String a_fromAlias)


Supported API: false

Method Summary

String	getActualTableAlias(Vector a_tableInfos, Vector a_aliases)
Class	getActualTargetClass(Vector a_tableInfos, Vector a_aliases)
private AliasDescriptor	getAliasDescriptor(Class a_class)
String	getAttributeName() Gets the value of the attribute: attributeName; The class's attribute.
Object	getBindParameter() Gets the value of the attribute: bindParameter; Returns a bind parameter for this expression (if supported).
List	getClassAttributes() Supported API: false
String	getColumnAlias() Gets the value of the attribute: columnAlias; Alias for the column expression.
ColumnDescriptor	getColumnDescriptor() Gets the value of the attribute: columnDescriptor; The associated introspection ColumnDescriptor.
TableExpression	getCorrelatedTable() Gets the value of the attribute: correlatedTable.
String	getExpression(boolean a_useBind, Vector a_tableInfos, Vector a_aliases, boolean a_outerJoin) Return string representation of this expression.
String	getFromAlias() Supported API: false
int	getFromCount() Gets the value of the attribute: fromCount; Number of from index values that this expression requires Supported API: false
Class	getJavaType() Gets the value of the attribute: javaType; The java type of this expression.
String	getTableAliasInView(Vector a_tableInfos, Vector a_aliases)
Class	getTargetClass() Gets the object for the association that plays role: targetClass.
String	getViewTableAlias() Gets the value of the attribute: viewTableAlias.
Class	getViewTableClass() Gets the value of the attribute: viewTableClass.
boolean	isAdvancedQuery() Gets the value of the attribute: advancedQuery; Indicates if the expression uses advanced query capabilities.
boolean	isAdvancedQueryEnabled() Gets the value of the attribute: advancedQueryEnabled; Indicates if advanced query capabilities are enabled.
boolean	isCorrelated() Gets the value of the attribute: correlated.
boolean	isUseViewTableAlias() Gets the value of the attribute: useViewTableAlias.
void	readExternal(ObjectInput input) Reads the non-transient fields of this class from an external source.
private boolean	readOldVersion(ObjectInput input, long readSerialVersionUID, boolean passThrough, boolean superDone) Reads the non-transient fields of this class from an external source, which is not the current version.
protected boolean	readVersion(ClassAttribute thisObject, ObjectInput input, long readSerialVersionUID, boolean passThrough, boolean superDone) Reads the non-transient fields of this class from an external source.
void	setAdvancedQueryEnabled(boolean a_AdvancedQueryEnabled) Sets the value of the attribute: advancedQueryEnabled; Indicates if advanced query capabilities are enabled.
void	setAttributeName(String a_AttributeName) Sets the value of the attribute: attributeName; The class's attribute.
void	setColumnAlias(String a_ColumnAlias) Sets the value of the attribute: columnAlias; Alias for the column expression.
void	setCorrelated(boolean a_Correlated) Sets the value of the attribute: correlated.
void	setCorrelatedTable(TableExpression a_CorrelatedTable) Sets the value of the attribute: correlatedTable.
int	setFromAlias(String[] a_aliases, int a_offset) This method sets the FROM clause alias for this expression.
void	setTargetClass(Class a_TargetClass) Sets the object for the association that plays role: targetClass.
void	setUseViewTableAlias(boolean a_UseViewTableAlias) Sets the value of the attribute: useViewTableAlias.
void	setViewTableAlias(String a_ViewTableAlias) Sets the value of the attribute: viewTableAlias.
void	setViewTableClass(Class a_ViewTableClass) Sets the value of the attribute: viewTableClass.
private void	targetClassValidate(Class a_TargetClass)
String	toString()
private boolean	validate(Class a_class, String a_attribute)
int	validate(TableExpression[] a_tableExpressions, int a_offset) This method validates this expression against the specified table expression.
void	writeExternal(ObjectOutput output) Writes the non-transient fields of this class to an external source.

Methods inherited from class java.lang.Object

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

Field Detail

RESOURCE

private static final String RESOURCE

See Also:

Constant Field Values

CLASSNAME

private static final String CLASSNAME

attributeName

private String attributeName

alias

private String alias

useExplicitAlias

private boolean useExplicitAlias

viewTableAlias

private String viewTableAlias

viewTableClass

private Class viewTableClass

useViewTableAlias

private boolean useViewTableAlias

correlated

private boolean correlated

correlatedTable

private TableExpression correlatedTable

targetClass

private Class targetClass

columnAlias

private String columnAlias

advancedQueryEnabled

private transient boolean advancedQueryEnabled

serialVersionUID

static final long serialVersionUID

See Also:

Constant Field Values

EXTERNALIZATION_VERSION_UID

public static final long EXTERNALIZATION_VERSION_UID

See Also:

Constant Field Values

OLD_FORMAT_VERSION_UID

protected static final long OLD_FORMAT_VERSION_UID

See Also:

Constant Field Values

columnDescriptor

private transient ColumnDescriptor columnDescriptor

javaType

private transient Class javaType

Constructor Detail

ClassAttribute

public ClassAttribute(Class a_targetClass,
                      String a_attributeName)
               throws QueryException

Supported API: true

Parameters:

a_targetClass - Specifies the class.

a_attributeName - Specifies the class's attribute.

Throws:

QueryException

ClassAttribute

public ClassAttribute(Class a_targetClass,
                      String a_attributeName,
                      String a_fromAlias)
               throws QueryException

Supported API: false

Parameters:

a_targetClass - Specifies the class.

a_attributeName - Specifies the class attribute.

a_fromAlias - Specifies a FROM clause table alias that will be used when constructing the expression.

Throws:

QueryException

ClassAttribute

public ClassAttribute()

Supported API: false

Method Detail

writeExternal

public void writeExternal(ObjectOutput output)
                   throws IOException

Writes the non-transient fields of this class to an external source.

Supported API: false

Specified by:

writeExternal in interface Externalizable

Parameters:

output -

Throws:

IOException

readExternal

public void readExternal(ObjectInput input)
                  throws IOException,
                         ClassNotFoundException

Reads the non-transient fields of this class from an external source.

Supported API: false

Specified by:

readExternal in interface Externalizable

Parameters:

input -

Throws:

IOException

ClassNotFoundException

readVersion

protected boolean readVersion(ClassAttribute thisObject,
                              ObjectInput input,
                              long readSerialVersionUID,
                              boolean passThrough,
                              boolean superDone)
                       throws IOException,
                              ClassNotFoundException

Reads the non-transient fields of this class from an external source.

Supported API: false

Parameters:

thisObject -

input -

readSerialVersionUID -

passThrough -

superDone -

Returns:

boolean

Throws:

IOException

ClassNotFoundException

readOldVersion

private boolean readOldVersion(ObjectInput input,
                               long readSerialVersionUID,
                               boolean passThrough,
                               boolean superDone)
                        throws IOException,
                               ClassNotFoundException

Reads the non-transient fields of this class from an external source, which is not the current version.

Parameters:

input -

readSerialVersionUID -

passThrough -

superDone -

Returns:

boolean

Throws:

IOException

ClassNotFoundException

getAttributeName

public String getAttributeName()

Gets the value of the attribute: attributeName; The class's attribute.

Supported API: true

Returns:

String

setAttributeName

public void setAttributeName(String a_AttributeName)
                      throws WTPropertyVetoException

Sets the value of the attribute: attributeName; The class's attribute.

Supported API: true

Parameters:

a_AttributeName -

Throws:

WTPropertyVetoException

getColumnDescriptor

public ColumnDescriptor getColumnDescriptor()
                                     throws PersistenceException

Gets the value of the attribute: columnDescriptor; The associated introspection ColumnDescriptor.

Supported API: false

Returns:

ColumnDescriptor

Throws:

PersistenceException

getViewTableAlias

public String getViewTableAlias()

Gets the value of the attribute: viewTableAlias.

Supported API: false

Returns:

String

setViewTableAlias

public void setViewTableAlias(String a_ViewTableAlias)

Sets the value of the attribute: viewTableAlias.

Supported API: false

Parameters:

a_ViewTableAlias -

getViewTableClass

public Class getViewTableClass()

Gets the value of the attribute: viewTableClass.

Supported API: false

Returns:

Class

setViewTableClass

public void setViewTableClass(Class a_ViewTableClass)

Sets the value of the attribute: viewTableClass.

Supported API: false

Parameters:

a_ViewTableClass -

isUseViewTableAlias

public boolean isUseViewTableAlias()

Gets the value of the attribute: useViewTableAlias.

Supported API: false

Returns:

boolean

setUseViewTableAlias

public void setUseViewTableAlias(boolean a_UseViewTableAlias)

Sets the value of the attribute: useViewTableAlias.

Supported API: false

Parameters:

a_UseViewTableAlias -

isCorrelated

public boolean isCorrelated()

Gets the value of the attribute: correlated.

Supported API: false

Returns:

boolean

setCorrelated

public void setCorrelated(boolean a_Correlated)

Sets the value of the attribute: correlated.

Supported API: false

Parameters:

a_Correlated -

getCorrelatedTable

public TableExpression getCorrelatedTable()

Gets the value of the attribute: correlatedTable.

Supported API: false

Returns:

TableExpression

setCorrelatedTable

public void setCorrelatedTable(TableExpression a_CorrelatedTable)

Sets the value of the attribute: correlatedTable.

Supported API: false

Parameters:

a_CorrelatedTable -

getTargetClass

public Class getTargetClass()

Gets the object for the association that plays role: targetClass.

Supported API: true

Returns:

Class

setTargetClass

public void setTargetClass(Class a_TargetClass)
                    throws WTPropertyVetoException

Sets the object for the association that plays role: targetClass.

Supported API: true

Parameters:

a_TargetClass -

Throws:

WTPropertyVetoException

targetClassValidate

private void targetClassValidate(Class a_TargetClass)
                          throws WTPropertyVetoException

Parameters:

a_TargetClass -

Throws:

WTPropertyVetoException

getFromAlias

public String getFromAlias()

Supported API: false

Returns:

String

getColumnAlias

public String getColumnAlias()

Gets the value of the attribute: columnAlias; Alias for the column expression.

Supported API: true

Specified by:

getColumnAlias in interface ColumnExpression

Returns:

String

setColumnAlias

public void setColumnAlias(String a_ColumnAlias)
                    throws WTPropertyVetoException

Sets the value of the attribute: columnAlias; Alias for the column expression.

Supported API: true

Specified by:

setColumnAlias in interface ColumnExpression

Parameters:

a_ColumnAlias -

Throws:

WTPropertyVetoException

getJavaType

public Class getJavaType()
                  throws WTException

Gets the value of the attribute: javaType; The java type of this expression.

Supported API: false

Specified by:

getJavaType in interface ColumnExpression

Returns:

Class

Throws:

WTException

isAdvancedQuery

public boolean isAdvancedQuery()
                        throws WTException

Gets the value of the attribute: advancedQuery; Indicates if the expression uses advanced query capabilities.

Supported API: false

Specified by:

isAdvancedQuery in interface ColumnExpression

Returns:

boolean

Throws:

WTException

isAdvancedQueryEnabled

public boolean isAdvancedQueryEnabled()

Gets the value of the attribute: advancedQueryEnabled; Indicates if advanced query capabilities are enabled.

Supported API: false

Specified by:

isAdvancedQueryEnabled in interface ColumnExpression

Returns:

boolean

setAdvancedQueryEnabled

public void setAdvancedQueryEnabled(boolean a_AdvancedQueryEnabled)

Sets the value of the attribute: advancedQueryEnabled; Indicates if advanced query capabilities are enabled.

Supported API: false

Specified by:

setAdvancedQueryEnabled in interface ColumnExpression

Parameters:

a_AdvancedQueryEnabled -

getFromCount

public int getFromCount()

Gets the value of the attribute: fromCount; Number of from index values that this expression requires

Supported API: false

Specified by:

getFromCount in interface Expression

Returns:

int

validate

public int validate(TableExpression[] a_tableExpressions,
                    int a_offset)
             throws QueryException

This method validates this expression against the specified table expression. A QueryException is thrown if this expression is not valid.

Supported API: false

Specified by:

validate in interface Expression

Parameters:

a_tableExpressions - Table expression to validate against.

a_offset - Offset index into the TableExpression array for the next valid TableExpression

Returns:

number of TableExpressions validated

Throws:

QueryException

setFromAlias

public int setFromAlias(String[] a_aliases,
                        int a_offset)

This method sets the FROM clause alias for this expression. This alias is used in this Expression in place of the corresponding TableExpression.

Supported API: false

Specified by:

setFromAlias in interface Expression

Parameters:

a_aliases - Array of aliases for expressions

a_offset - Offset index into the alias array for the next valid alias

Returns:

number of aliases used

getBindParameter

public Object getBindParameter()
                        throws WTException

Gets the value of the attribute: bindParameter; Returns a bind parameter for this expression (if supported).

Supported API: false

Specified by:

getBindParameter in interface RelationalExpression

Returns:

Object

Throws:

WTException

getExpression

public String getExpression(boolean a_useBind,
                            Vector a_tableInfos,
                            Vector a_aliases,
                            boolean a_outerJoin)
                     throws QueryException

Return string representation of this expression.

Supported API: false

Specified by:

getExpression in interface RelationalExpression

Parameters:

a_useBind - Indicates that bind variables should be used for this expression.

a_tableInfos -

a_aliases -

a_outerJoin - Indicates that outer join syntax should be used for this expression.

Returns:

String

Throws:

QueryException

getClassAttributes

public List getClassAttributes()

Supported API: false

Specified by:

getClassAttributes in interface RelationalExpression

Returns:

List

getActualTargetClass

public Class getActualTargetClass(Vector a_tableInfos,
                                  Vector a_aliases)
                           throws WTException

Throws:

WTException

getTableAliasInView

public String getTableAliasInView(Vector a_tableInfos,
                                  Vector a_aliases)
                           throws WTException

Throws:

WTException

getActualTableAlias

public String getActualTableAlias(Vector a_tableInfos,
                                  Vector a_aliases)
                           throws WTException

Throws:

WTException

toString

public String toString()

getAliasDescriptor

private AliasDescriptor getAliasDescriptor(Class a_class)
                                    throws WTException

Throws:

WTException

validate

private boolean validate(Class a_class,
                         String a_attribute)
                  throws WTException

Throws:

WTException