org.lastbamboo.common.sdp.api
Class SdpFactory

java.lang.Object
  org.lastbamboo.common.sdp.api.SdpFactory

public class SdpFactory
extends Object

The SdpFactory enables applications to encode and decode SDP messages. The SdpFactory can be used to construct a SessionDescription object programmatically. The SdpFactory can also be used to construct a SessionDescription based on the contents of a String. Acknowledgement: Bugs reported by Brian J. Collins . and by Majdi Abuelbassal . Please refer to IETF RFC 2327 for a description of SDP.

Version:

1.0

Author:

Olivier Deruelle , M. Ranganathan This code is in the public domain.

Field Summary

protected static List

sessionDescriptionsList

Constructor Summary

SdpFactory()

Method Summary

Attribute	createAttribute(String name, String value) Returns Attribute object with the specified values.
BandWidth	createBandwidth(String modifier, int value) Returns Bandwidth object with the specified values.
Connection	createConnection(String addr) Returns a Connection object with the specified address.
Connection	createConnection(String addr, int ttl, int numAddrs) Returns a Connection object with the specified properties and a network and address type of "IN" and "IP4" respectively.
Connection	createConnection(String netType, String addrType, String addr) Returns a Connection object with the specified properties and no TTL and a default number of addresses (1).
Connection	createConnection(String netType, String addrType, String addr, int ttl, int numAddrs) Returns a Connection object with the specified properties a
EMail	createEMail(String value) Returns EMail object with the specified value.
Info	createInfo(String value) Returns Info object with the specified value.
Key	createKey(String method, String key) Returns Key object with the specified value.
Media	createMedia(String media, int port, int numPorts, String transport, Vector staticRtpAvpTypes) Returns Media object with the specified properties.
MediaDescription	createMediaDescription(String media, int port, int numPorts, String transport, int[] staticRtpAvpTypes) Returns MediaDescription object with the specified properties.
MediaDescription	createMediaDescription(String media, int port, int numPorts, String transport, String[] formats) Returns MediaDescription object with the specified properties.
Origin	createOrigin(String userName, long sessionId, long sessionVersion, String networkType, String addrType, String address) Returns Origin object with the specified properties.
Origin	createOrigin(String userName, String address) Returns Origin object with the specified properties.
Phone	createPhone(String value) Returns Phone object with the specified value.
RepeatTime	createRepeatTime(int repeatInterval, int activeDuration, int[] offsets) Returns a RepeatTime object with the specified interval, duration, and time offsets.
SessionDescription	createSessionDescription() Creates a new, empty SessionDescription.
SessionDescription	createSessionDescription(String s) Creates a SessionDescription populated with the information contained within the string parameter.
SessionName	createSessionName(String name) Returns SessionName object with the specified name.
Time	createTime() Returns an unbounded Time specification (i.e., "t=0 0").
Time	createTime(Date start, Date stop) Returns a Time specification with the specified start and stop times.
TimeDescription	createTimeDescription() Returns TimeDescription unbounded (i.e.
TimeDescription	createTimeDescription(Date start, Date stop) Returns TimeDescription object with the specified properties.
TimeDescription	createTimeDescription(Time t) Returns TimeDescription object with the specified properties.
TimeZoneAdjustment	createTimeZoneAdjustment(Date d, int offset) Constructs a timezone adjustment record.
URI	createURI(URL value) Returns URI object with the specified value.
Version	createVersion(int value) Returns Version object with the specified values.
static Vector	findSessions(String source) Returns a collection of Strings containing session description.
String	formatMulticastAddress(String addr, int ttl, int numAddrs) Returns a String containing the computed form for a multi-connection address.
static Date	getDateFromNtp(long ntpTime)
static SdpFactory	getInstance() Obtain an instance of an SdpFactory.
static long	getNtpTime(Date d) Returns a long containing the NTP value for a given Java Date.

Methods inherited from class java.lang.Object

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

Field Detail

sessionDescriptionsList

protected static final List sessionDescriptionsList

Constructor Detail

SdpFactory

public SdpFactory()

Method Detail

getInstance

public static SdpFactory getInstance()

Obtain an instance of an SdpFactory. This static method returns a factory instance. Once an application has obtained a reference to an SdpFactory it can use the factory to configure and obtain parser instances and to create SDP objects.

Returns:

a factory instance

Throws:

SdpException

createSessionDescription

public SessionDescription createSessionDescription()
                                            throws SdpException

Creates a new, empty SessionDescription. The session is set as follows: v=0 o=this.createOrigin ("user", NetworkUtils.getLocalHost().toString()); s=- t=0 0

Returns:

a new, empty SessionDescription.

Throws:

SdpException - SdpException, - if there is a problem constructing the SessionDescription.

createSessionDescription

public SessionDescription createSessionDescription(String s)
                                            throws SdpParseException

Creates a SessionDescription populated with the information contained within the string parameter. Note: unknown field types should not cause exceptions.

Parameters:

s - s - the sdp message that is to be parsed.

Returns:

a populated SessionDescription object.

Throws:

SdpParseException - SdpParseException - if there is a problem parsing the String.

createBandwidth

public BandWidth createBandwidth(String modifier,
                                 int value)

Returns Bandwidth object with the specified values.

Parameters:

modifier - modifier - the bandwidth type

value - the bandwidth value measured in kilobits per second

Returns:

bandwidth

createAttribute

public Attribute createAttribute(String name,
                                 String value)

Returns Attribute object with the specified values.

Parameters:

name - the namee of the attribute

value - the value of the attribute

Returns:

Attribute

createInfo

public Info createInfo(String value)

Returns Info object with the specified value.

Parameters:

value - the string containing the description.

Returns:

Info

createPhone

public Phone createPhone(String value)

Returns Phone object with the specified value.

Parameters:

value - the string containing the description.

Returns:

Phone

createEMail

public EMail createEMail(String value)

Returns EMail object with the specified value.

Parameters:

value - the string containing the description.

Returns:

EMail

createURI

public URI createURI(URL value)

Returns URI object with the specified value.

Parameters:

value - the URL containing the description.

Returns:

URI

Throws:

SdpException

createSessionName

public SessionName createSessionName(String name)

Returns SessionName object with the specified name.

Parameters:

name - the string containing the name of the session.

Returns:

SessionName

createKey

public Key createKey(String method,
                     String key)

Returns Key object with the specified value.

Parameters:

method - the string containing the method type.

key - the key to set

Returns:

Key

createVersion

public Version createVersion(int value)

Returns Version object with the specified values.

Parameters:

value - the version number.

Returns:

Version

createMedia

public Media createMedia(String media,
                         int port,
                         int numPorts,
                         String transport,
                         Vector staticRtpAvpTypes)
                  throws SdpException

Returns Media object with the specified properties.

Parameters:

media - the media type, eg "audio"

port - port number on which to receive media

numPorts - number of ports used for this media stream

transport - transport type, eg "RTP/AVP"

staticRtpAvpTypes - vector to set

Returns:

Media

Throws:

SdpException

createOrigin

public Origin createOrigin(String userName,
                           String address)
                    throws SdpException

Returns Origin object with the specified properties.

Parameters:

userName - the user name.

address - the IP4 encoded address.

Returns:

Origin

Throws:

SdpException - if the parameters are null

createOrigin

public Origin createOrigin(String userName,
                           long sessionId,
                           long sessionVersion,
                           String networkType,
                           String addrType,
                           String address)
                    throws SdpException

Returns Origin object with the specified properties.

Parameters:

userName - String containing the user that created the string.

sessionId - long containing the session identifier.

sessionVersion - long containing the session version.

networkType - String network type for the origin (usually "IN").

addrType - String address type (usually "IP4").

address - String IP address usually the address of the host.

Returns:

Origin object with the specified properties.

Throws:

SdpException - if the parameters are null

createMediaDescription

public MediaDescription createMediaDescription(String media,
                                               int port,
                                               int numPorts,
                                               String transport,
                                               int[] staticRtpAvpTypes)
                                        throws IllegalArgumentException,
                                               SdpException

Returns MediaDescription object with the specified properties. The returned object will respond to Media.getMediaFormats(boolean) with a Vector of media formats.

Parameters:

media - media -

port - port number on which to receive media

numPorts - number of ports used for this media stream

transport - transport type, eg "RTP/AVP"

staticRtpAvpTypes - list of static RTP/AVP media payload types which should be specified by the returned MediaDescription throws IllegalArgumentException if passed an invalid RTP/AVP payload type

Returns:

MediaDescription

Throws:

IllegalArgumentException

SdpException

createMediaDescription

public MediaDescription createMediaDescription(String media,
                                               int port,
                                               int numPorts,
                                               String transport,
                                               String[] formats)

Returns MediaDescription object with the specified properties. The returned object will respond to Media.getMediaFormats(boolean) with a Vector of String objects specified by the 'formats argument.

Parameters:

media - the media type, eg "audio"

port - port number on which to receive media

numPorts - number of ports used for this media stream

transport - transport type, eg "RTP/AVP"

formats - list of formats which should be specified by the returned MediaDescription

Returns:

MediaDescription

createTimeDescription

public TimeDescription createTimeDescription(Time t)
                                      throws SdpException

Returns TimeDescription object with the specified properties.

Parameters:

t - the Time that the time description applies to. Returns TimeDescription object with the specified properties.

Returns:

TimeDescription

Throws:

SdpException

createTimeDescription

public TimeDescription createTimeDescription()
                                      throws SdpException

Returns TimeDescription unbounded (i.e. "t=0 0");

Returns:

TimeDescription unbounded (i.e. "t=0 0");

Throws:

SdpException

createTimeDescription

public TimeDescription createTimeDescription(Date start,
                                             Date stop)
                                      throws SdpException

Returns TimeDescription object with the specified properties.

Parameters:

start - start time.

stop - stop time.

Returns:

TimeDescription

Throws:

SdpException - if the parameters are null

formatMulticastAddress

public String formatMulticastAddress(String addr,
                                     int ttl,
                                     int numAddrs)

Returns a String containing the computed form for a multi-connection address. Parameters: addr - connection address ttl - time to live (TTL) for multicast addresses numAddrs - number of addresses used by the connection Returns: a String containing the computed form for a multi-connection address.

createConnection

public Connection createConnection(String netType,
                                   String addrType,
                                   String addr,
                                   int ttl,
                                   int numAddrs)
                            throws SdpException

Returns a Connection object with the specified properties a

Parameters:

netType - network type, eg "IN" for "Internet"

addrType - address type, eg "IP4" for IPv4 type addresses

addr - connection address

ttl - time to live (TTL) for multicast addresses

numAddrs - number of addresses used by the connection

Returns:

Connection

Throws:

SdpException

createConnection

public Connection createConnection(String netType,
                                   String addrType,
                                   String addr)
                            throws SdpException

Returns a Connection object with the specified properties and no TTL and a default number of addresses (1).

Parameters:

netType - network type, eg "IN" for "Internet"

addrType - address type, eg "IP4" for IPv4 type addresses

addr - connection address

Returns:

Connection

Throws:

SdpException - if the parameters are null

createConnection

public Connection createConnection(String addr,
                                   int ttl,
                                   int numAddrs)
                            throws SdpException

Returns a Connection object with the specified properties and a network and address type of "IN" and "IP4" respectively.

Parameters:

addr - connection address

ttl - time to live (TTL) for multicast addresses

numAddrs - number of addresses used by the connection

Returns:

Connection

Throws:

SdpException

createConnection

public Connection createConnection(String addr)
                            throws SdpException

Returns a Connection object with the specified address. This is equivalent to createConnection("IN", "IP4", addr);

Parameters:

addr - connection address

Returns:

Connection

Throws:

SdpException - if the parameter is null

createTime

public Time createTime(Date start,
                       Date stop)
                throws SdpException

Returns a Time specification with the specified start and stop times.

Parameters:

start - start time

stop - stop time

Returns:

a Time specification with the specified start and stop times.

Throws:

SdpException - if the parameters are null

createTime

public Time createTime()

Returns an unbounded Time specification (i.e., "t=0 0").

Returns:

an unbounded Time specification (i.e., "t=0 0").

Throws:

SdpException

createRepeatTime

public RepeatTime createRepeatTime(int repeatInterval,
                                   int activeDuration,
                                   int[] offsets)

Returns a RepeatTime object with the specified interval, duration, and time offsets.

Parameters:

repeatInterval - the "repeat interval" in seconds

activeDuration - the "active duration" in seconds

offsets - the list of offsets relative to the start time of the Time object with which the returned RepeatTime will be associated

Returns:

RepeatTime

createTimeZoneAdjustment

public TimeZoneAdjustment createTimeZoneAdjustment(Date d,
                                                   int offset)

Constructs a timezone adjustment record.

Parameters:

d - the Date at which the adjustment is going to take place.

offset - the adjustment in number of seconds relative to the start time of the SessionDescription with which this object is associated.

Returns:

TimeZoneAdjustment

findSessions

public static Vector findSessions(String source)

Returns a collection of Strings containing session description. This method is no longer supported, as the semantics are unclear and the original implementation caused a memory leak.

Parameters:

source - String containing session descriptions.

Returns:

a collection of Strings containing session descriptions.

getDateFromNtp

public static Date getDateFromNtp(long ntpTime)

Parameters:

ntpTime - long to set

Returns:

Returns a Date object for a given NTP date value.

getNtpTime

public static long getNtpTime(Date d)

Returns a long containing the NTP value for a given Java Date.

Parameters:

d - Date to set

Returns:

long