com.ibm.as400.access
Class FieldDescription

java.lang.Object
  com.ibm.as400.access.FieldDescription

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

ArrayFieldDescription, BinaryFieldDescription, CharacterFieldDescription, DateFieldDescription, DBCSEitherFieldDescription, DBCSGraphicFieldDescription, DBCSOnlyFieldDescription, DBCSOpenFieldDescription, FloatFieldDescription, HexFieldDescription, PackedDecimalFieldDescription, TimeFieldDescription, TimestampFieldDescription, ZonedDecimalFieldDescription

public abstract class FieldDescription
extends Object
implements Serializable

The FieldDescription class is an abstract base class that allows the user to describe the data in a field with an AS400DataType object and a name. Optionally, the user can specify a data definition specification (DDS) field name and DDS keywords if the field will be used with the record level access classes to define a RecordFormat object with which to create a physical file. The FieldDescription class contains methods to set and get field attributes that are common to all field types.

Examples

• Using the FieldDescription classes with the Data queue classes
• Using the FieldDescription classes with the record-level database access classes
• Using the FieldDescription classes with the LineDataRecordWriter class

See Also:

Serialized Form

Field Summary

Modifier and Type	Field and Description
static int	ALIGN_LEFT This is only used for record level writing.
static int	ALIGN_RIGHT This is only used for record level writing.

Constructor Summary

Modifier	Constructor and Description
protected	FieldDescription() Constructs a FieldDescription object.
protected	FieldDescription(AS400DataType dataType, String name) Constructs a FieldDescription object.
protected	FieldDescription(AS400DataType dataType, String name, String ddsName) Constructs a FieldDescription object.

Method Summary

Modifier and Type	Method and Description
String	getALIAS() Returns the value specified for the ALIAS keyword for this field.
boolean	getALWNULL() Returns the value specified for the ALWNULL keyword for this field.
String	getCOLHDG() Returns the value specified for the COLHDG keyword for this field.
AS400DataType	getDataType() Returns the AS400DataType object describing this field, as specified on construction.
String	getDDSName() Returns the DDS name of this field, as specified on the construct.
Object	getDFT() Returns the value specified for the DFT keyword for this field.
String	getDFTCurrentValue() Returns the default value setting based on the current timestamp.
String	getFieldName() Returns the name of this field.
String[]	getKeyFieldFunctions() Returns the string specified for any key field-level keywords for this field.
int	getLayoutAlignment() Returns the layout alignment of this field.
int	getLayoutLength() Returns the layout length of this field.
int	getLength() Returns the length of this field.
String	getREFFLD() Returns the value specified for the REFFLD keyword for this field.
String	getTEXT() Returns the value specified for the TEXT keyword for this field.
boolean	isDFTCurrent() Indicates if the default value for this field is set to one of the SQL special values of CURRENT_DATE, CURRENT_TIME, or CURRENT_TIMESTAMP.
boolean	isDFTNull() Indicates if the DFT keyword for this field is set to *NULL.
void	setALIAS(String alias) Sets the value for the ALIAS keyword for this field.
void	setALWNULL(boolean allowNull) Sets the value for the ALWNULL keyword for this field.
void	setCOLHDG(String colHdg) Sets the value for the COLHDG keyword for this field.
protected void	setDataType(AS400DataType dataType) Sets the AS400DataType object describing this field.
void	setDDSName(String ddsName) Sets the DDS name of this field.
void	setFieldName(String fieldName) Sets the name of this field.
void	setKeyFieldFunctions(String[] keyFunctions) Sets the string to be specified for all key field-level keywords for this field.
void	setLayoutAlignment(int layoutAlignment) Sets the layout alignment of this field.
void	setLayoutAttributes(int layoutLength, int layoutAlignment) Sets the layout length and layout alignment of this field.
void	setLayoutLength(int layoutLength) Sets the layout length of this field.
void	setREFFLD(String refFld) Sets the value to be specified for the REFFLD keyword for this field.
void	setTEXT(String text) Sets the value to be specified for the TEXT keyword for this field.

Methods inherited from class java.lang.Object

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

Field Detail

ALIGN_LEFT

public static final int ALIGN_LEFT

This is only used for record level writing.

See Also:

Constant Field Values

ALIGN_RIGHT

public static final int ALIGN_RIGHT

This is only used for record level writing.

See Also:

Constant Field Values

Constructor Detail

FieldDescription

protected FieldDescription()

Constructs a FieldDescription object.

FieldDescription

protected FieldDescription(AS400DataType dataType,
                           String name)

Constructs a FieldDescription object. It uses the specified data type and name of the field. The length of the field will be the length specified on the AS400DataType object. The DDS name of the field will be name if name is 10 characters or less. The DDS name of the field will be name truncated to 10 characters if name is greater than 10 characters. The layout length will be the length of the field, and the layout alignment will be ALIGN_LEFT.

Parameters:

dataType - Describes the field and provides the conversion capability for the contents of the field.

name - The name of the field.

FieldDescription

protected FieldDescription(AS400DataType dataType,
                           String name,
                           String ddsName)

Constructs a FieldDescription object. It uses the specified data type, name, and DDS name of the field. The length of the field will be the length specified on the AS400DataType object. The layout length will be the length of the field, and the layout alignment will be ALIGN_LEFT.

Parameters:

dataType - Describes the field and provides the conversion capability for the contents of the field.

name - The name of the field.

ddsName - The DDS name of this field. This is the name of the field as it would appear in a DDS description of the field. The length of ddsName must be 10 characters or less.

Method Detail

getALIAS

public String getALIAS()

Returns the value specified for the ALIAS keyword for this field.

Returns:

The value specified for the ALIAS keyword for this field. If ALIAS was not specified for this field, an empty string is returned.

getALWNULL

public boolean getALWNULL()

Returns the value specified for the ALWNULL keyword for this field.

Returns:

The value specified for the ALWNULL keyword. If ALWNULL was not specified for this field, false is returned.

getCOLHDG

public String getCOLHDG()

Returns the value specified for the COLHDG keyword for this field.

Returns:

The value specified for the COLHDG keyword for this field. If COLHDG was not specified for this field, an empty string is returned.

getDataType

public AS400DataType getDataType()

Returns the AS400DataType object describing this field, as specified on construction.

Returns:

The AS400DataType object that describes this field. If the data type has not been specified for this field, null is returned.

getDFT

public Object getDFT()

Returns the value specified for the DFT keyword for this field.

Returns:

The value specified for the DFT keyword for this field. If DFT was not specified for this field, null is returned.

getDFTCurrentValue

public String getDFTCurrentValue()

Returns the default value setting based on the current timestamp. If this field has had its default value set by calling setDFTCurrent(), then this method will return the value of the current Date, Time, or Timestamp to be used for that default value; otherwise, it returns null.

Returns:

The value being used as the "current" default value for this field. If DFT was not specified for this field, null is returned.

getDDSName

public String getDDSName()

Returns the DDS name of this field, as specified on the construct.

Returns:

The DDS name of this field. If the DDS name for this field has not been specified, an empty string is returned.

getFieldName

public String getFieldName()

Returns the name of this field.

Returns:

The name of this field. If the field name for this field has not been specified, an empty string is returned.

getKeyFieldFunctions

public String[] getKeyFieldFunctions()

Returns the string specified for any key field-level keywords for this field.

Returns:

The key field-level keywords that have been specified for this key field. If no key field functions have been specified, null is returned.

getLayoutAlignment

public int getLayoutAlignment()

Returns the layout alignment of this field. The layout alignment specifies the location of the data as presented within the layout length of the field. This value is only used in conjunction with line data record writer class, and only if the including record format is of type FIXED_LAYOUT_LENGTH.

Returns:

The layout alignment of this field.

getLayoutLength

public int getLayoutLength()

Returns the layout length of this field. The layout length is the actual character length of the field when written using the line data record writer class. The layout length is only valid if the including record format is of type FIXED_LAYOUT_LENGTH.

Returns:

The layout length of this field.

getLength

public int getLength()

Returns the length of this field. If this field is a character field (single byte or double byte, date, time, timestamp), the length is the number of characters allowed in the field. If this field is a numeric field (binary, float, packed, zoned), the length is the total number of digits allowed in the field. If this field is a hexadecimal field, the length is the number of bytes allowed in the field.

Returns:

The length of the field.

getREFFLD

public String getREFFLD()

Returns the value specified for the REFFLD keyword for this field.

Returns:

The value specified for the REFFLD keyword for this field. If REFFLD was not specified for this field, an empty string is returned.

getTEXT

public String getTEXT()

Returns the value specified for the TEXT keyword for this field.

Returns:

The value specified for the TEXT keyword for this field. If TEXT was not specified for this field, an empty string is returned.

isDFTCurrent

public boolean isDFTCurrent()

Indicates if the default value for this field is set to one of the SQL special values of CURRENT_DATE, CURRENT_TIME, or CURRENT_TIMESTAMP.

Returns:

True if the default value is set to one of the above.

setALIAS

public void setALIAS(String alias)

Sets the value for the ALIAS keyword for this field.

Parameters:

alias - The alias for this field.

setALWNULL

public void setALWNULL(boolean allowNull)

Sets the value for the ALWNULL keyword for this field.

Parameters:

allowNull - true if null is allowed; false otherwise.

setCOLHDG

public void setCOLHDG(String colHdg)

Sets the value for the COLHDG keyword for this field.

Parameters:

colHdg - The value for the COLHDG keyword for this field.
Format: "'Col heading 1' 'Col heading 2' 'Col heading 3'"
Examples:

                        String colHdg = "'Name'";
                        String colHdg = "'Employee' 'Number'";
                        String colHdg = "'Name' 'And' 'Address'";
                     

setDataType

protected void setDataType(AS400DataType dataType)

Sets the AS400DataType object describing this field.

Parameters:

dataType - The AS400DataType that describes this field. The dataType cannot be null.

setDDSName

public void setDDSName(String ddsName)

Sets the DDS name of this field.

Parameters:

ddsName - The DDS name of this field. The ddsName cannot be more than 10 characters in length.

setFieldName

public void setFieldName(String fieldName)

Sets the name of this field.

Parameters:

fieldName - The name of this field. The fieldName cannot be null.

setKeyFieldFunctions

public void setKeyFieldFunctions(String[] keyFunctions)

Sets the string to be specified for all key field-level keywords for this field.

Parameters:

keyFunctions - The key field-level keywords to be specified for this key field. The keyFunctions must contain at least one element.

setLayoutAlignment

public void setLayoutAlignment(int layoutAlignment)

Sets the layout alignment of this field. The layout alignment specifies the location of the data as presented within the layout length of the field. This value is only used in conjunction with the line data record writer class, and only if the including record format is of type FIXED_LAYOUT_LENGTH.

The following special values are valid:

• ALIGN_LEFT - Left alignment of data within the field layout.
• ALIGN_RIGHT - Right alignment of data within the field layout.

Parameters:

layoutAlignment - The layout alignment of this field.

setLayoutAttributes

public void setLayoutAttributes(int layoutLength,
                                int layoutAlignment)

Sets the layout length and layout alignment of this field. The layout length is the actual character length of the field when written using the line data record writer class. The layout length must be 50 characters or less. The layout alignment specifies the location of the data as presented within the layout length of the field. These values are only used in conjunction with the line data record writer class, and only if the including record format is of type FIXED_LAYOUT_LENGTH.

The following special values for the layout alignment are valid:

• ALIGN_LEFT - Left alignment of data within the field layout.
• ALIGN_RIGHT - Right alignment of data within the field layout.

Parameters:

layoutLength - The layout length of this field.

layoutAlignment - The layout alignment of this field.

setLayoutLength

public void setLayoutLength(int layoutLength)

Sets the layout length of this field. The layout length is the actual character length of the field when written using the line data record writer class. The layout length is only valid if the including record format is of type FIXED_LAYOUT_LENGTH. The layout length must be 50 characters or less. NOTE: The layout length does not have to equal the length of the field.

Parameters:

layoutLength - The layout length of this field.

setREFFLD

public void setREFFLD(String refFld)

Sets the value to be specified for the REFFLD keyword for this field.

Parameters:

refFld - The value for the REFFLD keyword for this field.

setTEXT

public void setTEXT(String text)

Sets the value to be specified for the TEXT keyword for this field.

Parameters:

text - The value for the TEXT keyword for this field. The single quotes required to surround the TEXT keyword value are added by this class. The text must be 50 characters or less in length.

isDFTNull

public boolean isDFTNull()

Indicates if the DFT keyword for this field is set to *NULL.

Returns:

True if the DFT keyword is set to *NULL.