com.opencloud.slee.resources.in.datatypes.cc

Class Signal

java.lang.Object

com.opencloud.util.AbstractDataObject

com.opencloud.util.AbstractFieldsObject

AbstractEncodedDataObject<T>

AbstractLazyEncodedDataObject<byte[]>

AbstractLazyEncodedByteArray

com.opencloud.slee.resources.in.datatypes.cc.Signal

All Implemented Interfaces:

DataObject, FastSerializable, Serializable

public final class Signal
extends AbstractLazyEncodedByteArray
implements FastSerializable

Class Signal conveys information to a user concerning tones and alerting signals. It represents the ASN.1 OCTET STRING types Core-INAP-CS1-DataTypes.AlertingPattern and CAP-datatypes.AlertingPattern.

The API offered by this class is as if the type were specified in ASN.1 as follows.

 Signal ::= SEQUENCE {
     signalValue SignalValue
 }

The class takes care of encoding the field value into a byte-array and decoding the field value from a byte-array, the encoded representation being as tabulated below.

Data Encoding - based on ITU-T Q.931 (05/98) §4.5.28 p99
	8	7	6	5	4	3	2	1
Octet 1	0	Signal information element identifier
Octet 2	0	Length of signal contents
Octet 3	Signal value

The octet numbering in the above table is that used in the cited standard.

Based on Q.931 1998-05 p99, the value of Signal information element identifier is always 0110100, and the value of Length of signal contents is always 0000001.

Based on ETSI TS 101 046 v7.1.0 p38, the Signal information element identifier and Length of signal contents are both ignored; their values are always 0000000.

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static class	Signal.SignalValue Subset of signal value constants, alerting-related signals only.

Field Summary

Fields inherited from class AbstractLazyEncodedDataObject

isDecoded

Fields inherited from class AbstractEncodedDataObject

encoded

Fields inherited from class com.opencloud.util.AbstractFieldsObject

FIELD_ABSENT, FIELD_UNINITIALISED

Constructor Summary

Constructors

Constructor and Description
Signal() Constructs a new Signal object with no fields set.
Signal(byte[] data) Constructs a new Signal object from network-encoded data.
Signal(byte[] data, int start, int len) Constructs a new Signal object from part of network-encoded data.
Signal(DataInput in) Constructs a new Signal object from data deserialized from a stream that was written by toStream(DataOutput).
Signal(Signal.SignalValue signalValue) Constructs a new Signal object from given values for all fields.

Method Summary

Methods

Modifier and Type	Method and Description
void	checkFieldsSet() Checks that all mandatory fields are present.
Signal	clone() Constructs a copy of this object and everything reachable from it.
static Signal	copyOf(Signal from) Creates a new object of this type, cloning the values of common fields from the given object of any subclass of the same base type.
protected void	decode() Computes the decoded form from the encoded form.
protected void	encode() Computes the encoded form from the decoded form.
protected boolean	encodedIsInvalid() Determines whether the encoded form is invalid.
byte[]	getCapEncodedForm() Gets the ETSI TS 101 046 v7.1.0 encoded form of this signal.
static int	getContainedLength(byte[] data, int start, int len) Determines the length of the encoded value that commences at offset start in the given data.
byte[]	getEncodedForm() Gets the encoded form.
static FieldAccessor[]	getFieldAccessors() Gets a new array of the accessors for fields of this type.
Map<String,Object>	getFieldsMap(boolean withAbsents) Gets a Map from field-name to field-value for the fields of a sequence.
byte[]	getInapEncodedForm() Gets the ITU Recommendation Q.931 encoded form of this signal.
Signal.SignalValue	getSignalValue() Gets the value of the signal value.
boolean	hasSignalValue() Tests whether the field SignalValue has a value.
Signal	setSignalValue(Signal.SignalValue value) Sets the value of the signal value.
void	toStream(DataOutput out) Serializes this object to a stream in a form suitable for reading by Signal(DataInput).

Methods inherited from class AbstractLazyEncodedDataObject

checkDecode, checkModifyAndDecode

Methods inherited from class com.opencloud.util.AbstractFieldsObject

equals, hashCode, toString

Methods inherited from class com.opencloud.util.AbstractDataObject

checkModify, isReadOnly, setReadOnly

Methods inherited from class java.lang.Object

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

Constructor Detail

Signal

public Signal()

Constructs a new Signal object with no fields set.

Signal

public Signal(byte[] data)

Constructs a new Signal object from network-encoded data. The data is not decoded and might not be decodable.

Parameters:

data - network-encoded data

Throws:

NullPointerException - if data is null

Signal

public Signal(byte[] data,
      int start,
      int len)

Constructs a new Signal object from part of network-encoded data. The part starts at index start and is len bytes long. The data is not decoded and might not be decodable.

Parameters:

data - network-encoded data

start - starting offset of network-encoded data in byte array

len - default length if not predictable

Throws:

NullPointerException - if data is null

IllegalArgumentException - if len is negative

Signal

public Signal(Signal.SignalValue signalValue)

Constructs a new Signal object from given values for all fields.

Parameters:

signalValue - the signal value

Signal

public Signal(DataInput in)
       throws IOException

Constructs a new Signal object from data deserialized from a stream that was written by toStream(DataOutput).

Parameters:

in - the stream to read from

Throws:

EOFException - if reading is pre-empted by end-of-file

IOException - if the data cannot be read

Method Detail

toStream

public void toStream(DataOutput out)
              throws IOException

Serializes this object to a stream in a form suitable for reading by Signal(DataInput).

Specified by:

toStream in interface FastSerializable

Parameters:

out - the stream to write to

Throws:

IOException - if an I/O error occurs

hasSignalValue

public boolean hasSignalValue()
                       throws DecodeException

Tests whether the field SignalValue has a value.

Returns:

whether the field has a value

Throws:

DecodeException - if encoded state cannot be decoded

checkFieldsSet

public void checkFieldsSet()
                    throws EncodeException

Checks that all mandatory fields are present. Should be called immediately before all calls to encode().

Specified by:

checkFieldsSet in class AbstractLazyEncodedDataObject<byte[]>

Throws:

EncodeException - if any mandatory field is not present

getSignalValue

public Signal.SignalValue getSignalValue()
                                  throws DecodeException

Gets the value of the signal value.

Returns:

SignalValue representation of the signal value

Throws:

DecodeException - if encoded state cannot be decoded

setSignalValue

public Signal setSignalValue(Signal.SignalValue value)
                      throws IllegalStateException

Sets the value of the signal value.

Parameters:

value - SignalValue representation of the signal value

Returns:

this

Throws:

IllegalStateException

copyOf

public static Signal copyOf(Signal from)

Creates a new object of this type, cloning the values of common fields from the given object of any subclass of the same base type.

Parameters:

from - the object from which to copy

Returns:

Signal

clone

public Signal clone()

Constructs a copy of this object and everything reachable from it.

Specified by:

clone in interface DataObject

Specified by:

clone in class AbstractDataObject

Returns:

copy of object

getFieldAccessors

public static FieldAccessor[] getFieldAccessors()

Gets a new array of the accessors for fields of this type.

Returns:

FieldAccessor[]

getFieldsMap

public Map<String,Object> getFieldsMap(boolean withAbsents)

Gets a Map from field-name to field-value for the fields of a sequence. For a field of primitive type, the field-value is boxed. For an absent optional field, the field-value is AbstractFieldsObject.FIELD_ABSENT. For an uninitialised mandatory field, the field-value is AbstractFieldsObject.FIELD_UNINITIALISED. For a field of String type, the encoded form is used if the String cannot be decoded. For a type that represents an OCTET STRING that cannot be decoded, a map from "encodedValue" to the byte array value is returned.

Specified by:

getFieldsMap in class AbstractFieldsObject

Parameters:

withAbsents - whether to put absent optional fields into Map

Returns:

Map from field-name to field-value

encodedIsInvalid

protected boolean encodedIsInvalid()

Determines whether the encoded form is invalid.

Returns:

boolean

getEncodedForm

public byte[] getEncodedForm()
                      throws EncodeException

Gets the encoded form.

Returns:

encoded form

Throws:

EncodeException - if encoding fails

getContainedLength

public static int getContainedLength(byte[] data,
                     int start,
                     int len)

Determines the length of the encoded value that commences at offset start in the given data. The value is not fully decoded and might not be decodable. Values of this type are of a fixed length, so that length is returned if the data is long enough, otherwise 0 is returned.

Parameters:

data - network-encoded data

start - index into data where value commences

len - length in data to be considered

Returns:

3, or 0 if encoded value is not long enough

getInapEncodedForm

public byte[] getInapEncodedForm()

Gets the ITU Recommendation Q.931 encoded form of this signal.

Returns:

a byte array containing the ITU Recommendation Q.931 encoded form of this signal

getCapEncodedForm

public byte[] getCapEncodedForm()

Gets the ETSI TS 101 046 v7.1.0 encoded form of this signal.

Returns:

a byte array containing the ETSI TS 101 046 v7.1.0 encoded form of this signal

encode

protected void encode()
               throws EncodeException

Computes the encoded form from the decoded form.

Specified by:

encode in class AbstractLazyEncodedDataObject<byte[]>

Throws:

EncodeException - if SignalValue is not in range [0,255]

decode

protected void decode()
               throws DecodeException

Computes the decoded form from the encoded form.

Specified by:

decode in class AbstractLazyEncodedDataObject<byte[]>

Throws:

DecodeException - if not 3 octets to be decoded