1. Identifying the underlying bearer, ESG spec used in the implementation:
import javax.microedition.broadcast.esg;
ServiceGuide esg = ServiceGuide.getDefaultServiceGuide();
MetadataSet spec;
MetadataSet[] speclist = esg.getSupportedMetadataSets();
for (int i = 0; i < speclist.length; i++) {
System.out.println("Metadata Specification: " +
speclist[i].getDescription());
// Check the class for the different types of spec; DVBH in this case.
if (speclist[i] instanceof CommonMetadataSet) {
// ....
}
}
2. Enumerate all the valid attributes in the specs:
ServiceGuide esg = ServiceGuide.getDefaultServiceGuide();
MetadataSet spec;
MetadataSet[] speclist = esg.getSupportedMetadataSets();
for (int i = 0; i < speclist.length; i++) {
Attribute[] attrs = speclist[i].getValidAttributes();
for (int j = 0; j < attrs.length; j++) {
// Eumerate the attributes and print out their long (proper) names.
System.out.println("Attribute: " + attrs[j].getName());
}
}
3. Find all the programs of a particular genre, then display it:
// Form the query
ServiceGuide esg = ServiceGuide.getDefaultServiceGuide();
Query q = QueryComposer.equivalent(CommonMetadataSet.PROGRAM_CONTENT_GENRE, "News");
// Because some programs of our interest may be updated asynchronously,
// we should also add a listener to make sure that we get updated
// on all the programs we are interested in.
// We'll go through this in Example 4.
try {
esg.addListener(new ProgramMonitor(), q);
} catch (QueryException qe) {
// invalid query
}
ProgramEvent programs[];
try {
// Find the programs
programs = esg.findPrograms(q);
for (int i = 0; i < programs.length; i++) {
// A custom function to display the program info
// Example 5.
displayProgramInfo(programs[i]);
}
} catch (QueryException e) {
}
4. Listen to program updates:
// Define my own program change listener for monitoring
// program updates.
class ProgramMonitor implements ServiceGuideListener {
public void serviceGuideUpdated(String event, ServiceGuideData esgdata, Object data) {
if (event == NEW_PROGRAM_LISTED || event == PROGRAM_CHANGED) {
// Display the new program
displayProgramInfo(esgdata);
}
else if (event == SERVICE_GUIDE_BULK_CHANGED || event == PROGRAM_DELETED) {
// We'll need to redo the queries and redisplay
// the programs. See Example 3.
}
}
}
5. Display "Generic" program information:
void displayProgramInfo(ProgramEvent p) {
Attribute[] attrs = CommonMetadataSet.getInstance().getValidAttributes();
for (int i = 0; i < attrs.length; i++) {
// Since we do not know ahead of time what the type
// of the attributes are, we will need to test for
// them one by one with "instanceof".
// The following format* methods format and display the
// values in some meaningful ways in the GUI. They are
// left as exercise for the readers.
formatAttribute(attrs[i].getName());
if (attrs[i] instanceof StringAttribute) {
formatString(p.getValue((StringAttribute)attrs[i]));
}
else if (attrs[i] instanceof DateAttribute) {
formatDate(p.getValue((DateAttribute)attrs[i]));
}
// More...
}
}
6. Display the Electronic Service Guide in the traditional time listing format:
ServiceGuide esg;
// Listen for all incoming programs.
// Listener to be defined later.
try {
esg.addListener(new ProgramMonitor(), null);
} catch(QueryException qe) {}
void displayServiceGuide() {
Attribute[] sortBy = new Attribute[] {
CommonMetadataSet.SERVICE_ID,
CommonMetadataSet.PROGRAM_START_TIME
};
try {
// Select all programs and sort them first by their service ids,
// then the scheduled start time.
ProgramEvent[] programs = esg.findPrograms(null, sortBy, 0, 0);
for (int i = 0; i < programs.length; i++)
displayProgramInfo(programs[i]);
} catch (QueryException e) {
}
}
public class ProgramMonitor implements ServiceGuideListener {
public void serviceGuideUpdated(String event, ServiceGuideData esgdata, Object data) {
if (event == NEW_PROGRAM_LISTED || event == PROGRAM_DELETED ||
event == SERVICE_GUIDE_UPDATE_COMPLETED) {
// It is easier to simply update the entire list
// and get the display sorted properly.
displayServiceGuide();
}
else if (event == PROGRAM_CHANGED) {
// Display the changed program
displayProgramInfo(esgdata);
}
}
}
7. Create query to get all programs today on PRO7 between 6 pm and 10 pm:
// calculate the dates for 6 pm and 10 pm today
Calendar c = Calendar.getInstance();
// use 17:59:59 instead of 18:00:00 to get programs starting 6 pm exactly
c.set(Calendar.HOUR, 17);
c.set(Calendar.MINUTE, 59);
c.set(Calendar.SECOND, 59);
Date startTime = c.getTime();
c.set(Calendar.HOUR, 22);
c.set(Calendar.MINUTE, 00);
c.set(Calendar.SECOND, 00);
Date endTime = c.getTime();
// create queries
Query qChannel = QueryComposer.equivalent(CommonMetadataSet.SERVICE_NAME, "PRO7");
Query qAfter = QueryComposer.after(CommonMetadataSet.PROGRAM_START_TIME, startTime);
Query qBefore = QueryComposer.before(CommonMetadataSet.PROGRAM_END_TIME, endTime);
// combine queries to one
Query q = QueryComposer.and(qChannel, QueryComposer.and(qAfter, qBefore));
ServiceGuide esg = ServiceGuide.getDefaultServiceGuide();
ProgramEvent programs[];
try {
// Find the programs
programs = esg.findPrograms(q);
for (int i = 0; i < programs.length; i++) {
displayProgramInfo(programs[i]);
}
} catch (QueryException e) { }
8. Create query to get all programs on YLE in Finnish or Swedish
// find all multilingual programs, both in Finnish and Swedish, on YLE
Query qChannel = QueryComposer.equivalent(CommonMetadataSet.SERVICE_NAME, "YLE");
Query qFinnish = QueryComposer.equivalent(CommonMetadataSet.SERVICE_COMPONENT_LANGUAGE, "fin");
Query qSwedish = QueryComposer.equivalent(CommonMetadataSet.SERVICE_COMPONENT_LANGUAGE, "swe");
// combine queries to one
Query q = QueryComposer.and(qChannel, QueryComposer.and(qFinnish, qSwedish));
ServiceGuide esg = ServiceGuide.getDefaultServiceGuide();
ProgramEvent programs[];
try {
// Find the programs
programs = esg.findPrograms(q);
for (int i = 0; i < programs.length; i++) {
displayProgramInfo(programs[i]);
}
} catch (QueryException e) { }
9. Changing the current service of the context where the calling application belong:
ServiceGuide esg = ServiceGuide.getDefaultServiceGuide();
try {
Service[] current = esg.findServices(QueryComposer.currentProgram());
ServiceContext sc = ServiceContext.getDefaultContext();
sc.select(current[0]);
} catch (Exception e) { }
10. Selecting a service based on the ESG:
ServiceGuide esg = ServiceGuide.getDefaultServiceGuide();
Query q = QueryComposer.equivalent(CommonMetadataSet.SERVICE_NAME, "BBC");
try {
Service[] services = esg.findServices(q);
if (services.length > 0) {
ServiceContext sc = ServiceContext.getDefaultContext();
sc.select(services[0]);
}
} catch (Exception e) { }
11. Selecting a service and fetch the Players for presentation
import javax.microedition.broadcast.*;
import javax.microedition.broadcast.esg.*;
import javax.microedition.media.*;
import javax.microedition.media.control.*;
ServiceContext sc = ServiceContext.getDefaultContext();
/**
* Add a listener to be notified of the creation of the Players.
* Initialize and start the Players as they are created.
*/
sc.addListener(new ServiceContextListener() {
public void contextUpdate(ServiceContext s, String event, Object data) {
if (event == ServiceContextListener.PLAYERS_REALIZED) {
Player players[] = (Player [])data;
// The players should all be realized at this point.
// Initialize and display them.
for (int i = 0; i < players.length; i++) {
VideoControl vc = (VideoControl)players[i].getControl("VideoControl");
if (vc != null) {
vc.initDisplayMode(vc.USE_DIRECT_VIDEO, canvas /* a GUI canvas created ahead of time */);
vc.setVisible(true);
}
}
}
}
});
// Select a service.
ServiceGuide esg = ServiceGuide.getDefaultServiceGuide();
try {
Service[] current = esg.findServices(QueryComposer.currentProgram());
sc.select(current[0]);
} catch (QueryException qe) {}
12. Using AMMS controls
import javax.microedition.broadcast.*;
import javax.microedition.media.*;
import javax.microedition.amms.control.audioeffect.*;
import javax.microedition.amms.control.imageeffect.*;
// Fetch EqualizerControl from a realized Player that was fetched
// from ServiceContext as in example 11.
EqualizerControl eq = (EqualizerControl)player.getControl("javax.microedition.amms.control.audioeffect.EqualizerControl");
if (eq != null) {
// Equalizer is supported.
// Let's boost the bass a little bit:
eq.setBass(70);
eq.setEnabled(true);
}
// Similarly , fetch an ImageTonalityControl.
ImageTonalityControl it = (ImageTonalityControl)player.getControl("javax.microedition.amms.control.audioeffect.ImageTonalityControl");
if (it != null) {
// Image tonality settings are supported.
// Let's increase image contrast:
it.setContrast(75);
it.setEnabled(true);
}
13. Working with Broadcast Objects: Retrieving typed packet streams
import javax.microedition.broadcast.*;
import javax.microedition.broadcast.connection.*;
import java.util.*;
/**
* Return all packet streams found in this service.
* This example excludes files and directories and includes
* available raw data from A/V components.
*
* @return a list of all available packet streams
*/
public Vector getTypedPacketStreams() {
// request the default service context
ServiceContext serviceContext = ServiceContext.getDefaultContext();
// get all selected components
ServiceComponent[] components = serviceContext.getSelectedComponents();
Vector connections = new Vector();
for (int i = 0; i < components.length; i++) {
try {
BroadcastConnection connection = serviceContext.getBroadcastDatagramConnection(components[i]);
// only add datagram connections to the list
connections.addElement(components[i]);
} catch (BroadcastServiceException e) {
// ignore connections that cannot be retrieved from the context
}
}
return connections;
}
/**
* Return all auxiliary packet data connections of a certain type.
*/
public Vector getPacketStream(String mimeType) {
Vector packetStreams = getPacketStreams();
Vector typedPacketStreams = new Vector();
Enumeration packetStreamEnum = packetStreams.elements();
while(packetStreamEnum.hasMoreElements()) {
BroadcastDatagramConnection connection = (BroadcastDatagramConnection)packetStreamEnum.nextElement();
// selectively add only connections of a certain mime type
if(connection.getMimeType().startsWith(mimeType)) {
typesPacketStreams.addElement(connection);
}
}
return typedPacketStreams;
}
14. Working with Auxiliary Data: Getting an Auxiliary Service Logo
import javax.microedition.broadcast.*;
import javax.microedition.broadcast.esg.*;
import javax.microedition.broadcast.connection.*;
import javax.microedition.io.*;
import java.io.*;
/**
* This method retrieves the logo associated with a service.
*/
public InputConnection getServiceLogo() throws IOException, QueryException {
// request the default service context
ServiceContext serviceContext = ServiceContext.getDefaultContext();
// Retrieve content logo uri
String logoUri = serviceContext.getService().getStringValue(CommonMetadataSet.PROGRAM_CONTENT_AUX_LOGO);
// Open the URI. The URI could be http, file or carousel-based.
// So we'll cast and use it as an InputConnection.
if (logoUri == null)
return null;
Connection logoConnection = Connector.open(logoUri, Connector.READ);
if (logoConnection instanceof InputConnection) {
return (InputConnection) logoConnection;
}
return null;
}
/**
* Just a skeleton to handle the service logo.
*/
public void handleServiceLogo() {
try {
InputConnection ic = getServiceLogo();
// We may want to specialize the code here.
if (ic instanceof HttpConnection) {
// Do something specific for http.
} else if (ic instanceof BroadcastFileConnection) {
// Do something specific for carousel.
BroadcastFileConnection bfc = (BroadcastFileConnection)ic;
if (!bfc.isAvailable())
bfc.addListener(myLogoListener);
else {
// Get additional information like mimetype and load image.
}
}
} catch (Exception e) {
}
}
15. Subscribe to a "premium movie service"
ServiceGuide db = ServiceGuide.getDefaultServiceGuide();
Query q = QueryComposer.equivalent(CommonMetadataSet.SERVICE_NAME, "PremiumMovies");
try {
Service[] services = db.findServices(q);
if (services.length > 0) {
Service premium = services[0];
String premiumServiceID = services[0].getStringValue(CommonMetadataSet.SERVICE_ID);
PurchaseObjects[] purchaseObjects = SubscriptionManager.getPurchaseObjects(serviceId);
if(purchaseObjects.length > 0) {
// show the content of the purchaseObjects to the user and
// and let him choose
// let's assume that the first purhchaseObject was selected by the user
if (purchaseObjects[0].isPurchased()) {
// user has already subscribed to the service, no need to buy it again
return;
}
purchaseObjects[0].addPurchaseListener(this);
// assume that the options are known to the user requestPriceOptions() is not needed
PriceOption[] options = purchaseObjects[0].getPriceOptions();
// at this point the different options should be presented to the user
purchaseObjects[0].purchase(options[0]);
// purchase transaction has been started.
// implementation pops up a dialog to get confirmation from the user
// application can now just wait for it to complete
}
}
} catch (Exception e) { }
void purchaseResponse(PurchaseObject source, java.lang.String event, java.lang.Object object) {
if (event.equals(PURCHASE_STARTED)) {
// purchase process started
return;
}
if (event.equals(PURCHASE_DENIED)) {
// user denied the purchasing
return;
}
if (event.equals(PURCHASE_APPROVED)) {
// user denied the purchasing
return;
}
if (event.equals(PURCHASE_COMPLETED)) {
// user denied the purchasing
return;
}
if (event.equals(PURCHASE_FAILED)) {
// user denied the purchasing
return;
}
}