javax.bluetooth
Class DataElement

java.lang.Object
  |
  +--javax.bluetooth.DataElement

public class DataElement

extends java.lang.Object

The DataElement class defines the various data types that a Bluetooth service attribute value may have. The following table describes the data types and valid values that a DataElement object can store.

Data Type	Valid Values
NULL	represents a null value
U_INT_1	long value range [0, 255]
U_INT_2	long value range [0, 216-1]
U_INT_4	long value range [0, 232-1]
U_INT_8	byte[] value range [0, 264-1]
U_INT_16	byte[] value range [0, 2128-1]
INT_1	long value range [-128, 127]
INT_2	long value range [-215, 215-1]
INT_4	long value range [-231, 231-1]
INT_8	long value range [-263, 263-1]
INT_16	byte[] value range [-2127, 2127-1]
URL	java.lang.String
UUID	javax.bluetooth.UUID
BOOL	boolean
STRING	java.lang.String
DATSEQ	java.util.Enumeration
DATALT	java.util.Enumeration

Field Summary

static int	BOOL Defines data of type BOOL.
static int	DATALT Defines data of type DATALT.
static int	DATSEQ Defines data of type DATSEQ.
static int	INT_1 Defines a signed integer of size one byte.
static int	INT_16 Defines a signed integer of size sixteen bytes.
static int	INT_2 Defines a signed integer of size two bytes.
static int	INT_4 Defines a signed integer of size four bytes.
static int	INT_8 Defines a signed integer of size eight bytes.
static int	NULL Defines data of type NULL.
static int	STRING Defines data of type STRING.
static int	U_INT_1 Defines an unsigned integer of size one byte.
static int	U_INT_16 Defines an unsigned integer of size sixteen bytes.
static int	U_INT_2 Defines an unsigned integer of size two bytes.
static int	U_INT_4 Defines an unsigned integer of size four bytes.
static int	U_INT_8 Defines an unsigned integer of size eight bytes.
static int	URL Defines data of type URL.
static int	UUID Defines data of type UUID.

Constructor Summary

DataElement(boolean bool)
Creates a DataElement whose data type is BOOL and whose value is equal to bool

DataElement(int valueType)
Creates a DataElement of type NULL, DATALT, or DATSEQ.

DataElement(int valueType, long value)
Creates a DataElement that encapsulates an integer value of size U_INT_1, U_INT_2, U_INT_4, INT_1, INT_2, INT_4, and INT_8.

DataElement(int valueType, java.lang.Object value)
Creates a DataElement whose data type is given by valueType and whose value is specified by the argument value.

Method Summary

void	addElement(DataElement elem) Adds a DataElement to this DATALT or DATSEQ DataElement object.
boolean	getBoolean() Returns the value of the DataElement if it is represented as a boolean.
int	getDataType() Returns the data type of the object this DataElement represents.
long	getLong() Returns the value of the DataElement if it can be represented as a long.
int	getSize() Returns the number of DataElements that are present in this DATALT or DATSEQ object.
java.lang.Object	getValue() Returns the value of this DataElement as an Object.
void	insertElementAt(DataElement elem, int index) Inserts a DataElement at the specified location.
boolean	removeElement(DataElement elem) Removes the first occurrence of the DataElement from this object.

Methods inherited from class java.lang.Object

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

Field Detail

NULL

public static final int NULL

Defines data of type NULL. The value for data type DataElement.NULL is implicit, i.e., there is no representation of it. Accordingly there is no method to retrieve it, and attempts to retrieve the value will throw an exception.

The value of NULL is 0x00 (0).

U_INT_1

public static final int U_INT_1

Defines an unsigned integer of size one byte.

The value of the constant U_INT_1 is 0x08 (8).

U_INT_2

public static final int U_INT_2

Defines an unsigned integer of size two bytes.

The value of the constant U_INT_2 is 0x09 (9).

U_INT_4

public static final int U_INT_4

Defines an unsigned integer of size four bytes.

The value of the constant U_INT_4 is 0x0A (10).

U_INT_8

public static final int U_INT_8

Defines an unsigned integer of size eight bytes.

The value of the constant U_INT_8 is 0x0B (11).

U_INT_16

public static final int U_INT_16

Defines an unsigned integer of size sixteen bytes.

The value of the constant U_INT_16 is 0x0C (12).

INT_1

public static final int INT_1

Defines a signed integer of size one byte.

The value of the constant INT_1 is 0x10 (16).

INT_2

public static final int INT_2

Defines a signed integer of size two bytes.

The value of the constant INT_2 is 0x11 (17).

INT_4

public static final int INT_4

Defines a signed integer of size four bytes.

The value of the constant INT_4 is 0x12 (18).

INT_8

public static final int INT_8

Defines a signed integer of size eight bytes.

The value of the constant INT_8 is 0x13 (19).

INT_16

public static final int INT_16

Defines a signed integer of size sixteen bytes.

The value of the constant INT_16 is 0x14 (20).

URL

public static final int URL

Defines data of type URL.

The value of the constant URL is 0x40 (64).

UUID

public static final int UUID

Defines data of type UUID.

The value of the constant UUID is 0x18 (24).

BOOL

public static final int BOOL

Defines data of type BOOL.

The value of the constant BOOL is 0x28 (40).

STRING

public static final int STRING

Defines data of type STRING.

The value of the constant STRING is 0x20 (32).

DATSEQ

public static final int DATSEQ

Defines data of type DATSEQ. The service attribute value whose data has this type must consider all the elements of the list, i.e. the value is the whole set and not a subset. The elements of the set can be of any type defined in this class, including DATSEQ.

The value of the constant DATSEQ is 0x30 (48).

DATALT

public static final int DATALT

Defines data of type DATALT. The service attribute value whose data has this type must consider only one of the elements of the set, i.e., the value is the not the whole set but only one element of the set. The user is free to choose any one element. The elements of the set can be of any type defined in this class, including DATALT.

The value of the constant DATALT is 0x38 (56).

Constructor Detail

DataElement

public DataElement(int valueType)

Creates a DataElement of type NULL, DATALT, or DATSEQ.

Parameters:

valueType - the type of DataElement to create: NULL, DATALT, or DATSEQ

Throws:

IllegalArgumentException - if valueType is not NULL, DATALT, or DATSEQ

See Also:

NULL, DATALT, DATSEQ

DataElement

public DataElement(boolean bool)

Creates a DataElement whose data type is BOOL and whose value is equal to bool

Parameters:

bool - the value of the DataElement of type BOOL.

See Also:

BOOL

DataElement

public DataElement(int valueType,
                   long value)

Creates a DataElement that encapsulates an integer value of size U_INT_1, U_INT_2, U_INT_4, INT_1, INT_2, INT_4, and INT_8. The legal values for the valueType and the corresponding attribute values are:

Value Type	Value Range
U_INT_1	[0, 28-1]
U_INT_2	[0, 216-1]
U_INT_4	[0, 232-1]
INT_1	[-27, 27-1]
INT_2	[-215, 215-1]
INT_4	[-231, 231-1]
INT_8	[-263, 263-1]

All other pairings are illegal and will cause an IllegalArgumentException to be thrown.

Parameters:

valueType - the data type of the object that is being created; must be one of the following: U_INT_1, U_INT_2, U_INT_4, INT_1, INT_2, INT_4, or INT_8

value - the value of the object being created; must be in the range specified for the given valueType

Throws:

IllegalArgumentException - if the valueType is not valid or the value for the given legal valueType is outside the valid range

See Also:

U_INT_1, U_INT_2, U_INT_4, INT_1, INT_2, INT_4, INT_8

DataElement

public DataElement(int valueType,
                   java.lang.Object value)

Creates a DataElement whose data type is given by valueType and whose value is specified by the argument value. The legal values for the valueType and the corresponding attribute values are:

Value Type	Java Type / Value Range
URL	java.lang.String
UUID	javax.bluetooth.UUID
STRING	java.lang.String
INT_16	[-2127, 2127-1] as a byte array whose length must be 16
U_INT_8	[0, 264-1] as a byte array whose length must be 8
U_INT_16	[0, 2128-1] as a byte array whose length must be 16

All other pairings are illegal and would cause an IllegalArgumentException exception.

Parameters:

valueType - the data type of the object that is being created; must be one of the following: URL, UUID, STRING, INT_16, U_INT_8, or U_INT_16

value - the value for the DataElement being created of type valueType

Throws:

IllegalArgumentException - if the value is not of the valueType type or is not in the range specified or is null

See Also:

URL, UUID, STRING, U_INT_8, INT_16, U_INT_16

Method Detail

addElement

public void addElement(DataElement elem)

Adds a DataElement to this DATALT or DATSEQ DataElement object. The elem will be added at the end of the list. The elem can be of any DataElement type, i.e., URL, NULL, BOOL, UUID, STRING, DATSEQ, DATALT, and the various signed and unsigned integer types. The same object may be added twice. If the object is successfully added the size of the DataElement is increased by one.

Parameters:

elem - the DataElement object to add

Throws:

ClassCastException - if the method is invoked on a DataElement whose type is not DATALT or DATSEQ

NullPointerException - if elem is null

insertElementAt

public void insertElementAt(DataElement elem,
                            int index)

Inserts a DataElement at the specified location. This method can be invoked only on a DATALT or DATSEQ DataElement. elem can be of any DataElement type, i.e., URL, NULL, BOOL, UUID, STRING, DATSEQ, DATALT, and the various signed and unsigned integers. The same object may be added twice. If the object is successfully added the size will be increased by one. Each element with an index greater than or equal to the specified index is shifted upward to have an index one greater than the value it had previously.

The index must be greater than or equal to 0 and less than or equal to the current size. Therefore, DATALT and DATSEQ are zero-based objects.

Parameters:

elem - the DataElement object to add

index - the location at which to add the DataElement

Throws:

ClassCastException - if the method is invoked on an instance of DataElement whose type is not DATALT or DATSEQ

IndexOutOfBoundsException - if index is negative or greater than the size of the DATALT or DATSEQ

NullPointerException - if elem is null

getSize

public int getSize()

Returns the number of DataElements that are present in this DATALT or DATSEQ object. It is possible that the number of elements is equal to zero.

Returns:

the number of elements in this DATALT or DATSEQ

Throws:

ClassCastException - if this object is not of type DATALT or DATSEQ

removeElement

public boolean removeElement(DataElement elem)

Removes the first occurrence of the DataElement from this object. elem may be of any type, i.e., URL, NULL, BOOL, UUID, STRING, DATSEQ, DATALT, or the variously sized signed and unsigned integers. Only the first object in the list that is equal to elem will be removed. Other objects, if present, are not removed. Since this class doesn�t override the equals() method of the Object class, the remove method compares only the references of objects. If elem is successfully removed the size of this DataElement is decreased by one. Each DataElement in the DATALT or DATSEQ with an index greater than the index of elem is shifted downward to have an index one smaller than the value it had previously.

Parameters:

elem - the DataElement to be removed

Returns:

true if the input value was found and removed; else false

Throws:

ClassCastException - if this object is not of type DATALT or DATSEQ

NullPointerException - if elem is null

getDataType

public int getDataType()

Returns the data type of the object this DataElement represents.

Returns:

the data type of this DataElement object; the legal return values are: URL, NULL, BOOL, UUID, STRING, DATSEQ, DATALT, U_INT_1, U_INT_2, U_INT_4, U_INT_8, U_INT_16, INT_1, INT_2, INT_4, INT_8, or INT_16

getLong

public long getLong()

Returns the value of the DataElement if it can be represented as a long. The data type of the object must be U_INT_1, U_INT_2, U_INT_4, INT_1, INT_2, INT_4, or INT_8.

Returns:

the value of the DataElement as a long

Throws:

ClassCastException - if the data type of the object is not U_INT_1, U_INT_2, U_INT_4, INT_1, INT_2, INT_4, or INT_8

getBoolean

public boolean getBoolean()

Returns the value of the DataElement if it is represented as a boolean.

Returns:

the boolean value of this DataElement object

Throws:

ClassCastException - if the data type of this object is not of type BOOL

getValue

public java.lang.Object getValue()

Returns the value of this DataElement as an Object. This method returns the appropriate Java object for the following data types: URL, UUID, STRING, DATSEQ, DATALT, U_INT_8, U_INT_16, and INT_16. Modifying the returned Object will not change this DataElement. The following are the legal pairs of data type and Java object type being returned.

DataElement Data Type	Java Data Type
URL	java.lang.String
UUID	javax.bluetooth.UUID
STRING	java.lang.String
DATSEQ	java.util.Enumeration
DATALT	java.util.Enumeration
U_INT_8	byte[] of length 8
U_INT_16	byte[] of length 16
INT_16	byte[] of length 16

Returns:

the value of this object

Throws:

ClassCastException - if the object is not a URL, UUID, STRING, DATSEQ, DATALT, U_INT_8, U_INT_16, or INT_16