Package FairCom.CtreeDb

Class CTField

Object

CTBase

CTField

public class CTField
extends CTBase

Deals with the field concept. The field is the basic component of the table; a table may be composed of as many fields as one needs. It uses CTBase as the base class and implements the constructor allocating memory and destructor freeing memory for field operations.

See Also:

• CTBase
• CTTable
• CTRecord
• CTIndex
• CTSegment

Field Summary

Fields inherited from class CTBase

m_handle

Constructor Summary

Constructors

Constructor	Description
CTField()	Default constructor for the CTField class.
CTField(CTField Field)	Copy constructor for the CTField class.

Method Summary

Modifier and Type	Method	Description
void	ClearFieldDefaultValue()	Clears the current field's default value.
void	CTFieldSetFieldDefaultDateTimeType()	Sets the default field value date and time type to be used when converting CT_DATE, CT_TIME and CT_TIMES String values.
int	GetCTType()	Retrieves the FIELD_TYPE.
int	GetFieldBinaryFlag()	Retrieves the field binary handling flag.
int	GetFieldDefaultDateType()	Retrieves the default value DATE_TYPE used when converting strings to dates.
int	GetFieldDefaultTimeType()	Retrieves the default value TIME_TYPE used when converting String to time.
String	GetFieldDefaultValue()	Retrieves the current field default value.
String	GetFieldStringEncoding()	Get the field string encoding.
int	GetLength()	Retrieves the field length.
String	GetName()	Retrieves the field name.
boolean	GetNullFlag()	Retrieves the field null flag.
int	GetNumber()	Retrieves the field position index in the CTTable field list.
int	GetPrecision()	Retrieves the field precision.
int	GetScale()	Retrieves the field scale.
int	GetStatus()	Retrieves the status of a field handle.
int	GetType()	Retrieves the FIELD_TYPE.
boolean	IsFieldDefaultValueSet()	Checks if a field default value has been set.
boolean	IsNumeric()	Checks if the field represents a numeric value.
void	SetFieldBinaryFlag(int Flag)	Sets the value of the field binary handling flag.
void	SetFieldDefaultDateTimeType(int DateType, int TimeType)	Sets the default field value date and time type to be used when converting CT_DATE, CT_TIME and CT_TIMES String values.
void	SetFieldDefaultValue(String Value)	Sets the field default value.
void	SetFieldStringEncoding(String encoding)	Set the field string encoding.
void	SetLength(int FieldLength)	Sets the field length.
void	SetName(String FieldName)	Sets the field name.
void	SetNullFlag(boolean flag)	Sets Null Flag.
void	SetPrecision(int precision)	Sets the field precision.
void	SetScale(int scale)	Sets the field scale value.
void	SetType(int FieldType, int FieldLength)	Sets the field FIELD_TYPE and length.

Methods inherited from class CTBase

Abort, Begin, ClearSavePoint, Commit, GetAutoCommit, GetHandle, GetKeepLock, GetLockMode, GetOperation, GetTransactionMode, IsLockActive, IsTransActive, IsUnicodeLib, Lock, PrepareCommit, RestoreSavePoint, SetAutoCommit, SetHandle, SetKeepLock, SetOperation, SetSavePoint, SetTransactionMode, Unlock

Methods inherited from class Object

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

Constructor Details

CTField

public CTField()

Default constructor for the CTField class.

See Also:

• CTField(CTField)

CTField

public CTField(CTField Field)

Copy constructor for the CTField class.

Parameters:

Field - CTField object to be copied.

See Also:

• CTField()

Method Details

GetName

public String GetName()

Retrieves the field name.

Returns:

Field name

See Also:

• SetName(java.lang.String)
• GetType()
• GetLength()
• IsNumeric()

GetType

public int GetType()

Retrieves the FIELD_TYPE.

Returns:

Current FIELD_TYPE value.

See Also:

• SetType(int, int)
• GetName()
• GetLength()
• GetCTType()

GetCTType

public int GetCTType()

Retrieves the FIELD_TYPE. Maintained for backward compatibility.

Returns:

Current FIELD_TYPE value.

See Also:

• SetType(int, int)
• GetName()
• GetLength()
• GetType()

GetLength

public int GetLength()

Retrieves the field length.

Returns:

Current field length.

See Also:

• SetLength(int)
• GetPrecision()
• GetScale()
• GetName()
• GetType()

SetName

public void SetName(String FieldName)
             throws CTException

Sets the field name.

Parameters:

FieldName - New field name value.

Throws:

CTException - in case of error

See Also:

• GetName()
• SetType(int, int)
• SetLength(int)

SetType

public void SetType(int FieldType,
 int FieldLength)
             throws CTException

Sets the field FIELD_TYPE and length.

Parameters:

FieldType - New FIELD_TYPE for the Field.

FieldLength - New length for the Field.

Throws:

CTException - in case of error

See Also:

• GetType()
• SetName(java.lang.String)
• SetLength(int)

SetLength

public void SetLength(int FieldLength)
               throws CTException

Sets the field length.

Parameters:

FieldLength - New length for the Field.

Throws:

CTException - in case of error

See Also:

• GetLength()
• SetPrecision(int)
• SetScale(int)
• SetName(java.lang.String)
• SetType(int, int)

GetNumber

public int GetNumber()
              throws CTException

Retrieves the field position index in the CTTable field list.

Returns:

Field position.

Throws:

CTException - in case of error

See Also:

• GetName()
• GetLength()
• GetType()

GetNullFlag

public boolean GetNullFlag()

Retrieves the field null flag.

Returns:

true if field is null, or false if it is not null.

See Also:

• SetNullFlag(boolean)
• GetNumber()
• GetName()

GetPrecision

public int GetPrecision()

Retrieves the field precision.

Returns:

Current field precision value.

See Also:

• SetPrecision(int)
• GetLength()
• GetScale()

GetScale

public int GetScale()

Retrieves the field scale.

Returns:

Current field scale value.

See Also:

• SetScale(int)
• GetLength()
• GetPrecision()

SetNullFlag

public void SetNullFlag(boolean flag)
                 throws CTException

Sets Null Flag.

Parameters:

flag - New field null flag. True if field is null, or false if it is not.

Throws:

CTException - in case of error

See Also:

• GetNullFlag()
• SetPrecision(int)
• SetScale(int)
• SetName(java.lang.String)
• SetType(int, int)

SetPrecision

public void SetPrecision(int precision)
                  throws CTException

Sets the field precision.

Parameters:

precision - New field precision value.

Throws:

CTException - in case of error

See Also:

• GetPrecision()
• SetNullFlag(boolean)
• SetScale(int)
• SetName(java.lang.String)
• SetType(int, int)

SetScale

public void SetScale(int scale)
              throws CTException

Sets the field scale value.

Parameters:

scale - New field scale value.

Throws:

CTException - in case of error

See Also:

• GetScale()
• SetNullFlag(boolean)
• SetPrecision(int)
• SetName(java.lang.String)
• SetType(int, int)

IsNumeric

public boolean IsNumeric()

Checks if the field represents a numeric value.

Returns:

true if field is numeric or false if it is not.

See Also:

• GetType()
• GetLength()

SetFieldDefaultValue

public void SetFieldDefaultValue(String Value)
                          throws CTException

Sets the field default value. The default value of a field is used during an alter table operation when a full table rebuild is performed. During a full alter table rebuild, and after the old record buffer data is moved to the new record buffer, the new record buffer is scanned and if a null field is found and that null field has a default value, the default value is copied to the field buffer.

The field default value is kept as a String representation of the data. It is recommended that numeric data should be converted to String using one of the rich set of c-treeDB data conversion functions.

Date values should be converted to String using the default date type value. The default date type value can be retrieved by calling GetFieldDefaultDateType() method. By default, the date type is CTDATE_MDCY.

Time values should be converted to String using the default time type value. The default time type value can be retrieved by calling GetFieldDefaultTimeType() function. By default, the time type is CTTIME_HMS.

Time stamp values should be converted to String using the default date type and time type values as described above.

Parameters:

Value - New field default value.

Throws:

CTException - in case of error

See Also:

• GetFieldDefaultValue()
• IsFieldDefaultValueSet()
• ClearFieldDefaultValue()
• SetFieldDefaultDateTimeType(int, int)

GetFieldDefaultValue

public String GetFieldDefaultValue()

Retrieves the current field default value. If no default value is set, GetFieldDefaultValue return zero. You can use IsFieldDefaultValueSet() method to check if a field default value is set or not.

Returns:

Current field default value.

See Also:

• SetFieldDefaultValue(java.lang.String)
• IsFieldDefaultValueSet()
• ClearFieldDefaultValue()
• SetFieldDefaultDateTimeType(int, int)

ClearFieldDefaultValue

public void ClearFieldDefaultValue()
                            throws CTException

Clears the current field's default value. The default date and time types are also reset to their default values of CTDATE_MDCY and CTTIME_HMS respectively.

Throws:

CTException - in case of error

See Also:

• SetFieldDefaultValue(java.lang.String)
• GetFieldDefaultValue()
• IsFieldDefaultValueSet()
• SetFieldDefaultDateTimeType(int, int)

CTFieldSetFieldDefaultDateTimeType

public void CTFieldSetFieldDefaultDateTimeType()
                                        throws CTException

Sets the default field value date and time type to be used when converting CT_DATE, CT_TIME and CT_TIMES String values. By default the date type is CTDATE_MDCY and the time type is CTTIME_HMS. Use this method to modify the default values.

Throws:

CTException - in case of error

See Also:

• SetFieldDefaultValue(java.lang.String)
• ClearFieldDefaultValue()
• IsFieldDefaultValueSet()
• SetFieldDefaultDateTimeType(int, int)

SetFieldDefaultDateTimeType

public void SetFieldDefaultDateTimeType(int DateType,
 int TimeType)
                                 throws CTException

Sets the default field value date and time type to be used when converting CT_DATE, CT_TIME and CT_TIMES String values. By default the date type is CTDATE_MDCY and the time type is CTTIME_HMS. Use this method to modify the default values.

SetFieldDefaultDateTimeType method modifies both the date and time types. If you wish to change only the default date time, but keep the current time type, use the following example:

hField.SetFieldDefaultDateTimeType(CTDATE_YMD, hField.GetFieldDefaultTimeType());

You can use the same approach to change only the time type, keeping the current date type:

hField.SetFieldDefaultDateTimeType( ctdbGetFieldDefaultDateType(), CTIME_HMP);

Parameters:

DateType - New DATE_TYPE field value.

TimeType - New TIME_TYPE field value.

Throws:

CTException - in case of error

See Also:

• SetFieldDefaultValue(java.lang.String)
• ClearFieldDefaultValue()
• IsFieldDefaultValueSet()
• SetFieldDefaultDateTimeType(int, int)

IsFieldDefaultValueSet

public boolean IsFieldDefaultValueSet()

Checks if a field default value has been set.

Returns:

true if a field default value was set, or false if it was not.

See Also:

• GetFieldDefaultValue()
• ClearFieldDefaultValue()
• SetFieldDefaultDateTimeType(int, int)

GetFieldDefaultDateType

public int GetFieldDefaultDateType()

Retrieves the default value DATE_TYPE used when converting strings to dates.

Returns:

Current DATE_TYPE default value.

See Also:

• GetFieldDefaultTimeType()
• GetFieldDefaultValue()
• ClearFieldDefaultValue()
• SetFieldDefaultValue(java.lang.String)

GetFieldDefaultTimeType

public int GetFieldDefaultTimeType()

Retrieves the default value TIME_TYPE used when converting String to time.

Returns:

Current TIME_TYPE default value

See Also:

• GetFieldDefaultDateType()
• GetFieldDefaultValue()
• ClearFieldDefaultValue()
• SetFieldDefaultValue(java.lang.String)

GetStatus

public int GetStatus()

Retrieves the status of a field handle. The status of a field handle is a bit map describing one or more FIELD_STATUS values.

Returns:

Current FIELD_STATUS value.

See Also:

• GetName()
• GetType()
• GetLength()
• GetNumber()

GetFieldBinaryFlag

public int GetFieldBinaryFlag()

Retrieves the field binary handling flag. The field BINARY_FLAG indicates how c-treeDB will handle CT_ARRAY, CT_F2STRING, and CT_2STRING fields.

Returns:

Current field BINARY_FLAG value.

See Also:

• SetFieldBinaryFlag(int)

SetFieldBinaryFlag

public void SetFieldBinaryFlag(int Flag)
                        throws CTException

Sets the value of the field binary handling flag. The field BINARY_FLAG indicates how c-treeDB will handle CT_ARRAY, CT_F2STRING and CT_2STRING fields.

Parameters:

Flag - New field BINARY_FLAG value.

Throws:

CTException - in case of error

See Also:

• GetFieldBinaryFlag()

SetFieldStringEncoding

public void SetFieldStringEncoding(String encoding)
                            throws CTException

Set the field string encoding.

Parameters:

encoding - a string describing the encoding used in the field content. CTDB does not enfore any check on the value passed in, yet JTDB, JDBC, Ado .Net provider and SQL server expect to be able to identify the encoding therefore use values as defined by IANA https://www.iana.org/assignments/character-sets/character-sets.xhtml

Throws:

CTException - in case of error

See Also:

• GetFieldStringEncoding()

GetFieldStringEncoding

public String GetFieldStringEncoding()
                              throws CTException

Get the field string encoding.

Returns:

Field string encoding value

Throws:

CTException - in case of error