com.jcorporate.expresso.core.dataobjects.jdbc
Class JoinedDataField

java.lang.Object
  com.jcorporate.expresso.core.dataobjects.jdbc.JoinedDataField

All Implemented Interfaces:

DataField

public class JoinedDataField

extends Object

implements DataField

Data Field that is aware of local/forein key relations. If you set the local key, it will set the foreign key as well. This i

Author:

Michael Rimov

Constructor Summary

protected

JoinedDataField() Protected constructor.

Method Summary

BigDecimal	asBigDecimal() Retrieve the wrapped object as a BigDecimal object or zero if we're unable to convert it.
Boolean	asBoolean() Retrieve the boolean object value.
Date	asDate() Retrieve the wrapped object as a Date object or possibly null if we can't convert it or the object is null.
Double	asDouble() Retrieve the wrapped object as a Double object or zero if we can't convert i
Integer	asInteger() Retrieves the wrapped object as an Integer or zero if it's an invalid format.
InputStream	asStream() Allows for retrieval of BLOB database types.
String	asString() Retrieves the wrapped object as a String
void	cacheIsChangedComparison() call when add() or update() has occurred, and currentValue of data fields should be considered 'original value' for purposes of determining 'isChanged'
void	checkValue() Make sure the value of the field is valid.
Map	getAllAttributes() Returns a Read Only Map of all attributes in name-value pairs.
Object	getAttribute(String attributeName) Retrieves any user defined attributes for this field.
DataFieldMetaData	getFieldMetaData() Returns a handle to the Field MetaData object.
static JoinedDataField	getInstance(JoinedDataObject owner, DataObject localObj, String localField, DataObject remoteObj, String foreignField) Construct a new JoinedDataField object
Object	getOriginalValue() Deprecated. 8/04 v.5.5 do not expose this cache
DataObject	getOwner() Returns a handle to the DataObject that is the container for this Data Field
Object	getValue() Retrieve the value of the object.
boolean	isChanged() Used for change logging.
boolean	isNull() Returns true if the object is null.
boolean	isValueSet() Used for change logging.
void	resetChanged() Resets the changed flag and sets the original value field to null
void	setAttribute(String attributeName, Object value) Sets an attribute for this particular instance of the Data field
void	setFieldMetaData(DataFieldMetaData newMetadata) Sets the metadata object for this field.
void	setOwner(DataObject newOwner) Sets the owner of a given DataObject
void	setValue(Object newValue) Sets the wrapped object for the data field

Methods inherited from class java.lang.Object

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

Constructor Detail

JoinedDataField

protected JoinedDataField()

Protected constructor. Do not use normally.

Method Detail

getInstance

public static JoinedDataField getInstance(JoinedDataObject owner,
                                          DataObject localObj,
                                          String localField,
                                          DataObject remoteObj,
                                          String foreignField)

Construct a new JoinedDataField object

Parameters:

owner - the creating data object

localObj - the 'Left' DataObject

localField - the 'Left' join field

remoteObj - the 'Right' DataObject

foreignField - the 'Right' join field.

Returns:

an instantiated JoinedDataField instance.

getValue

public Object getValue()

Retrieve the value of the object. It is the same with the local key AND the foreign key.

Specified by:

getValue in interface DataField

Returns:

java.lang.Object

asString

public String asString()

Description copied from interface: DataField

Retrieves the wrapped object as a String

Specified by:

asString in interface DataField

Returns:

java.lang.String

asBoolean

public Boolean asBoolean()

Description copied from interface: DataField

Retrieve the boolean object value.

Specified by:

asBoolean in interface DataField

Returns:

java.lang.Boolean

asInteger

public Integer asInteger()

Description copied from interface: DataField

Retrieves the wrapped object as an Integer or zero if it's an invalid format.

Specified by:

asInteger in interface DataField

Returns:

a java.lang.Integer object, or null if the object is null.

asDate

public Date asDate()

Description copied from interface: DataField

Retrieve the wrapped object as a Date object or possibly null if we can't convert it or the object is null.

Specified by:

asDate in interface DataField

Returns:

a properly instantiated Date Object if we're able to convert it.

asBigDecimal

public BigDecimal asBigDecimal()

Description copied from interface: DataField

Retrieve the wrapped object as a BigDecimal object or zero if we're unable to convert it.

Specified by:

asBigDecimal in interface DataField

Returns:

a properly instantiated BigDecimal Object if we're able to convert it.

asDouble

public Double asDouble()

Description copied from interface: DataField

Retrieve the wrapped object as a Double object or zero if we can't convert i

Specified by:

asDouble in interface DataField

Returns:

a properly instantiated Double Object if we're able to convert it.

getOriginalValue

public Object getOriginalValue()

Deprecated. 8/04 v.5.5 do not expose this cache

Specified by:

getOriginalValue in interface DataField

Returns:

the original object or null

asStream

public InputStream asStream()

Description copied from interface: DataField

Allows for retrieval of BLOB database types.

Specified by:

asStream in interface DataField

Returns:

java.io.InputStream

isChanged

public boolean isChanged()

Description copied from interface: DataField

Used for change logging.

Specified by:

isChanged in interface DataField

Returns:

true if the field has changed since the last reset

isValueSet

public boolean isValueSet()

Description copied from interface: DataField

Used for change logging.

Specified by:

isValueSet in interface DataField

Returns:

true if the field has been set since the last reset

checkValue

public void checkValue()
                throws DataException

Description copied from interface: DataField

Make sure the value of the field is valid.

Specified by:

checkValue in interface DataField

Throws:

DataException - if the field value is not valid

resetChanged

public void resetChanged()

Description copied from interface: DataField

Resets the changed flag and sets the original value field to null

Specified by:

resetChanged in interface DataField

setValue

public void setValue(Object newValue)

Description copied from interface: DataField

Sets the wrapped object for the data field

Specified by:

setValue in interface DataField

Parameters:

newValue - a new Object to set the value to

isNull

public boolean isNull()

Description copied from interface: DataField

Returns true if the object is null.

Specified by:

isNull in interface DataField

Returns:

true if the object is null

setAttribute

public void setAttribute(String attributeName,
                         Object value)

Description copied from interface: DataField

Sets an attribute for this particular instance of the Data field

Specified by:

setAttribute in interface DataField

Parameters:

attributeName - the name of the attribute to set

value - the value to set it to

getAttribute

public Object getAttribute(String attributeName)

Description copied from interface: DataField

Retrieves any user defined attributes for this field.

Specified by:

getAttribute in interface DataField

Parameters:

attributeName - the name of the attribute to retrieve

Returns:

an object or null if the attribute doesn't exist

getAllAttributes

public Map getAllAttributes()

Description copied from interface: DataField

Returns a Read Only Map of all attributes in name-value pairs. If there are no attributes then getAllAttributes will return a null map.

Specified by:

getAllAttributes in interface DataField

Returns:

java.util.map

getOwner

public DataObject getOwner()

Description copied from interface: DataField

Returns a handle to the DataObject that is the container for this Data Field

Specified by:

getOwner in interface DataField

Returns:

DataObject the containing data object.

setOwner

public void setOwner(DataObject newOwner)

Description copied from interface: DataField

Sets the owner of a given DataObject

Specified by:

setOwner in interface DataField

Parameters:

newOwner - The new parent object.

getFieldMetaData

public DataFieldMetaData getFieldMetaData()

Description copied from interface: DataField

Returns a handle to the Field MetaData object.

Specified by:

getFieldMetaData in interface DataField

Returns:

DataFieldMetaData

setFieldMetaData

public void setFieldMetaData(DataFieldMetaData newMetadata)

Description copied from interface: DataField

Sets the metadata object for this field.

Specified by:

setFieldMetaData in interface DataField

Parameters:

newMetadata - the new Field Meta data object... for example DBField

cacheIsChangedComparison

public void cacheIsChangedComparison()

call when add() or update() has occurred, and currentValue of data fields should be considered 'original value' for purposes of determining 'isChanged'

Specified by:

cacheIsChangedComparison in interface DataField