arlut.csd.ganymede
Class DateDBField

java.lang.Object
  |
  +--arlut.csd.ganymede.DBField
        |
        +--arlut.csd.ganymede.DateDBField

All Implemented Interfaces:

date_field, db_field, java.rmi.Remote

public class DateDBField

extends DBField

implements date_field

DateDBField is a subclass of DBField for the storage and handling of Date fields in the DBStore on the Ganymede server.

The Ganymede client talks to DateDBFields through the date_field RMI interface.

Ganymede uses the standard Java Date class, which can encode dates from roughly 300 million years B.C. to 300 million years A.D., with millisecond resolution. No Y2k problems here. ;-)

Field Summary

(package private) static java.text.DateFormat

formatter

Fields inherited from class arlut.csd.ganymede.DBField

fieldcode, owner, value

Constructor Summary

(package private)	DateDBField(arlut.csd.ganymede.DBObject owner, java.io.DataInput in, arlut.csd.ganymede.DBObjectBaseField definition) Receive constructor.
	DateDBField(arlut.csd.ganymede.DBObject owner, arlut.csd.ganymede.DateDBField field) Copy constructor.
	DateDBField(arlut.csd.ganymede.DBObject owner, java.util.Date value, arlut.csd.ganymede.DBObjectBaseField definition) Scalar value constructor.
(package private)	DateDBField(arlut.csd.ganymede.DBObject owner, arlut.csd.ganymede.DBObjectBaseField definition) No-value constructor.
	DateDBField(arlut.csd.ganymede.DBObject owner, java.util.Vector values, arlut.csd.ganymede.DBObjectBaseField definition) Vector value constructor.

Method Summary

java.lang.Object	clone()
(package private) void	emit(java.io.DataOutput out) This method is responsible for writing out the contents of this field to an binary output stream.
void	emitDateXML(arlut.csd.ganymede.XMLDumpContext xmlOut, java.util.Date value)
(package private) void	emitXML(arlut.csd.ganymede.XMLDumpContext xmlOut) This method is used when the database is being dumped, to write out this field to disk.
arlut.csd.ganymede.DBField	getCopy(arlut.csd.ganymede.DBObject newOwner) This method is used to return a copy of this field, with the field's owner set to newOwner.
java.lang.String	getDiffString(arlut.csd.ganymede.DBField orig) Returns a String representing the change in value between this field and orig.
java.lang.String	getEncodingString() Date fields need a special encoding that can be easily reversed to obtain a date object on the client for sorting and selection purposes.
java.lang.String	getValueString() Returns a String representing the value of this field.
boolean	limited() Returns true if this date field has a minimum and/or maximum date set.
java.util.Date	maxDate() Returns the latest date acceptable for this field
java.util.Date	minDate() Returns the earliest date acceptable for this field
(package private) void	receive(java.io.DataInput in, arlut.csd.ganymede.DBObjectBaseField definition) This method is responsible for reading in the contents of this field from an binary input stream.
java.util.Date	value()
java.util.Date	value(int index)
arlut.csd.ganymede.ReturnVal	verifyNewValue(java.lang.Object o) Overridable method to verify that an object submitted to this field has an appropriate value.
boolean	verifyTypeMatch(java.lang.Object o) Overridable method to determine whether an Object submitted to this field is of an appropriate type.

Methods inherited from class arlut.csd.ganymede.DBField

addElement, addElement, addElement, addElementLocal, addElements, addElements, addElements, addElements, addElementsLocal, checkpoint, cleanup, containsElement, containsElement, containsElementLocal, copyFieldTo, deleteAllElements, deleteElement, deleteElement, deleteElement, deleteElement, deleteElement, deleteElement, deleteElementLocal, deleteElementLocal, deleteElements, deleteElements, deleteElements, deleteElementsLocal, equals, getComment, getElement, getFieldDef, getFieldDef, getFieldDef, getFieldInfo, getFieldTemplate, getID, getMaxArraySize, getName, getNameSpace, getObjTypeID, getOwner, getType, getTypeDesc, getValue, getValue, getValueLocal, getValues, getValuesLocal, getVectorDiff, getVectVal, getXMLName, indexOfValue, isBuiltIn, isDefined, isEditable, isEditable, isEditInPlace, isVector, isVisible, key, key, mark, mark, rescanThisField, rollback, setElement, setElement, setElement, setElementLocal, setOwner, setUndefined, setValue, setValue, setValue, setValueLocal, size, toString, unmark, unmark, verifyReadPermission, verifyWritePermission

Methods inherited from class java.lang.Object

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

Methods inherited from interface arlut.csd.ganymede.db_field

addElement, addElements, containsElement, deleteAllElements, deleteElement, deleteElement, deleteElements, getComment, getElement, getFieldInfo, getFieldTemplate, getID, getName, getType, getTypeDesc, getValue, getValues, isBuiltIn, isDefined, isEditable, isEditInPlace, isVector, isVisible, setElement, setValue, size

Field Detail

formatter

static java.text.DateFormat formatter

Constructor Detail

DateDBField

DateDBField(arlut.csd.ganymede.DBObject owner,
            java.io.DataInput in,
            arlut.csd.ganymede.DBObjectBaseField definition)
      throws java.io.IOException

Receive constructor. Used to create a DateDBField from a DBStore/DBJournal DataInput stream.

DateDBField

DateDBField(arlut.csd.ganymede.DBObject owner,
            arlut.csd.ganymede.DBObjectBaseField definition)

No-value constructor. Allows the construction of a 'non-initialized' field, for use where the DBObjectBase definition indicates that a given field may be present, but for which no value has been stored in the DBStore.

Used to provide the client a template for 'creating' this field if so desired.

DateDBField

public DateDBField(arlut.csd.ganymede.DBObject owner,
                   arlut.csd.ganymede.DateDBField field)

Copy constructor.

DateDBField

public DateDBField(arlut.csd.ganymede.DBObject owner,
                   java.util.Date value,
                   arlut.csd.ganymede.DBObjectBaseField definition)

Scalar value constructor.

DateDBField

public DateDBField(arlut.csd.ganymede.DBObject owner,
                   java.util.Vector values,
                   arlut.csd.ganymede.DBObjectBaseField definition)

Vector value constructor.

Method Detail

getCopy

public arlut.csd.ganymede.DBField getCopy(arlut.csd.ganymede.DBObject newOwner)

This method is used to return a copy of this field, with the field's owner set to newOwner.

Specified by:

getCopy in class DBField

clone

public java.lang.Object clone()

Overrides:

clone in class java.lang.Object

emit

void emit(java.io.DataOutput out)
    throws java.io.IOException

Description copied from class: DBField

This method is responsible for writing out the contents of this field to an binary output stream. It is used in writing fields to the ganymede.db file and to the journal file.

This method only writes out the value contents of this field. The DBObject emit() method is responsible for writing out the field identifier information ahead of the field's contents.

Specified by:

emit in class DBField

java.io.IOException

receive

void receive(java.io.DataInput in,
             arlut.csd.ganymede.DBObjectBaseField definition)
       throws java.io.IOException

Description copied from class: DBField

This method is responsible for reading in the contents of this field from an binary input stream. It is used in reading fields from the ganymede.db file and from the journal file.

The code that calls receive() on this field is responsible for having read enough of the binary input stream's context to place the read cursor at the point in the file immediately after the field's id and type information has been read.

Specified by:

receive in class DBField

java.io.IOException

emitXML

void emitXML(arlut.csd.ganymede.XMLDumpContext xmlOut)
       throws java.io.IOException

This method is used when the database is being dumped, to write out this field to disk. It is mated with receiveXML().

Specified by:

emitXML in class DBField

java.io.IOException

emitDateXML

public void emitDateXML(arlut.csd.ganymede.XMLDumpContext xmlOut,
                        java.util.Date value)
                 throws java.io.IOException

java.io.IOException

value

public java.util.Date value()

value

public java.util.Date value(int index)

getValueString

public java.lang.String getValueString()

Description copied from interface: db_field

Returns a String representing the value of this field.

Specified by:

getValueString in interface db_field

Specified by:

getValueString in class DBField

getEncodingString

public java.lang.String getEncodingString()

Date fields need a special encoding that can be easily reversed to obtain a date object on the client for sorting and selection purposes.

Specified by:

getEncodingString in interface db_field

Specified by:

getEncodingString in class DBField

See Also:

db_field

getDiffString

public java.lang.String getDiffString(arlut.csd.ganymede.DBField orig)

Returns a String representing the change in value between this field and orig. This String is intended for logging and email, not for any sort of programmatic activity. The format of the generated string is not defined, but is intended to be suitable for inclusion in a log entry and in an email message.

If there is no change in the field, null will be returned.

Specified by:

getDiffString in class DBField

limited

public boolean limited()

Returns true if this date field has a minimum and/or maximum date set.

We depend on our owner's isDateLimited() method to tell us whether this Date field should be limited or not in this editing context.

Specified by:

limited in interface date_field

See Also:

date_field

minDate

public java.util.Date minDate()

Returns the earliest date acceptable for this field

We depend on our owner's minDate() method to tell us what the earliest acceptable Date for this field is.

Specified by:

minDate in interface date_field

See Also:

date_field

maxDate

public java.util.Date maxDate()

Returns the latest date acceptable for this field

We depend on our owner's maxDate() method to tell us what the earliest acceptable Date for this field is.

Specified by:

maxDate in interface date_field

See Also:

date_field

verifyTypeMatch

public boolean verifyTypeMatch(java.lang.Object o)

Description copied from class: DBField

Overridable method to determine whether an Object submitted to this field is of an appropriate type.

Specified by:

verifyTypeMatch in class DBField

verifyNewValue

public arlut.csd.ganymede.ReturnVal verifyNewValue(java.lang.Object o)

Description copied from class: DBField

Overridable method to verify that an object submitted to this field has an appropriate value.

Specified by:

verifyNewValue in class DBField