Package db

Class Field

java.lang.Object

db.Field

All Implemented Interfaces:

java.lang.Comparable<Field>

Direct Known Subclasses:

BinaryField, BooleanField, ByteField, IntField, LongField, ShortField, StringField

public abstract class Field
extends java.lang.Object
implements java.lang.Comparable<Field>

Field is an abstract data wrapper for use with Records. Note that when comparing two Field instances both must be of the same class.

Stored Schema Field Type Encoding:

8-bit Legacy Field Type Encoding (I....FFF)

Supported encodings: 0x00..0x06 and 0x80..0x86, where:

     FFF  - indexed field type (0..6)
     I    - index field indicator (only long primary keys were supported)
 

8-bit Field Type Encoding (PPPPFFFF)

(Reserved for future field extensions: 0x88 and 0xf0..0xff)

     0xff - see Schema.FIELD_EXTENSION_INDICATOR
 

where:

     FFFF - normal/indexed field type
     PPPP - indexed table primary key type (1000b: LegacyIndexField)  
 

Nested Class Summary

Nested Classes

Change	Modifier and Type	Class	Description
	static class	Field.UnsupportedFieldException

Field Summary

Fields

Change	Modifier and Type	Field	Description
NEW	static Field[]	EMPTY_ARRAY

Method Summary

Change	Modifier and Type	Method	Description
NEW	static boolean	canIndex(Field field)	Determine if a specified field instance may be indexed
NEW	abstract Field	copyField()	Create new instance of this field with the same value.
	abstract boolean	equals(java.lang.Object obj)
	abstract byte[]	getBinaryData()	Get data as a byte array.
	boolean	getBooleanValue()	Get field as a boolean value.
	byte	getByteValue()	Get field as a byte value.
	int	getIntValue()	Get field as an integer value.
	long	getLongValue()	Get field as a long value.
	short	getShortValue()	Get field as a short value.
	java.lang.String	getString()	Get field as a String value.
	abstract java.lang.String	getValueAsString()	Get field value as a formatted string
	abstract int	hashCode()
NEW	boolean	isSameType(Field field)	Determine if specified field is same type as this field
	boolean	isVariableLength()
	abstract Field	newField()	Create new instance of this field type.
	abstract void	setBinaryData(byte[] bytes)	Set data from binary byte array.
	void	setBooleanValue(boolean value)	Set field's boolean value.
	void	setByteValue(byte value)	Set field's byte value.
	void	setIntValue(int value)	Set field's integer value.
	void	setLongValue(long value)	Set field's long value.
	void	setShortValue(short value)	Set field's short value.
	void	setString(java.lang.String str)	Set field's String value.
REMOVED	Field	newField(Field fieldValue)	(Removed)

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Comparable

compareTo

Field Detail

EMPTY_ARRAY NEW

public static final Field[] EMPTY_ARRAY

Method Detail

getLongValue

public long getLongValue()

Get field as a long value. All fixed-length field objects must implement this method

Returns:

long value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

setLongValue

public void setLongValue(long value)

Set field's long value. All fixed-length field objects must implement this method

Parameters:

value - long value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

getIntValue

public int getIntValue()

Get field as an integer value.

Returns:

integer value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

setIntValue

public void setIntValue(int value)

Set field's integer value.

Parameters:

value - integer value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

getShortValue

public short getShortValue()

Get field as a short value.

Returns:

short value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

setShortValue

public void setShortValue(short value)

Set field's short value.

Parameters:

value - short value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

getByteValue

public byte getByteValue()

Get field as a byte value.

Returns:

byte value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

setByteValue

public void setByteValue(byte value)

Set field's byte value.

Parameters:

value - byte value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

getBooleanValue

public boolean getBooleanValue()

Get field as a boolean value.

Returns:

boolean value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

setBooleanValue

public void setBooleanValue(boolean value)

Set field's boolean value.

Parameters:

value - boolean value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

getBinaryData

public abstract byte[] getBinaryData()

Get data as a byte array.

Returns:

byte[]

setBinaryData

public abstract void setBinaryData(byte[] bytes)

Set data from binary byte array. All variable-length fields must implement this method.

Parameters:

bytes - field data

Throws:

IllegalFieldAccessException - if error occurs while reading bytes into field which will generally be caused by the incorrect number of bytes provided to a fixed-length field.

getString

public java.lang.String getString()

Get field as a String value.

Returns:

String value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

setString

public void setString(java.lang.String str)

Set field's String value.

Parameters:

str - String value

Throws:

IllegalFieldAccessException - thrown if method is not supported by specific Field instance.

isVariableLength

public boolean isVariableLength()

Returns:

true if a Field instance is variable length, else false.

isSameType NEW

public boolean isSameType(Field field)

Determine if specified field is same type as this field

Parameters:

field - a Field instance

Returns:

true if field is same type as this field

copyField NEW

public abstract Field copyField()

Create new instance of this field with the same value.

Returns:

new field instance with same value

newField

public abstract Field newField()

Create new instance of this field type.

Returns:

new field instance with undefined initial value

equals

public abstract boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

hashCode

public abstract int hashCode()

Overrides:

hashCode in class java.lang.Object

getValueAsString

public abstract java.lang.String getValueAsString()

Get field value as a formatted string

Returns:

field value string

canIndex NEW

public static boolean canIndex(Field field)

Determine if a specified field instance may be indexed

Parameters:

field - field to be checked

Returns:

true if field can be indexed