com.zebra.sdk.printer.discovery

Class NetworkDiscoverer

Object

com.zebra.sdk.printer.discovery.NetworkDiscoverer

public class NetworkDiscoverer
extends Object

A class used to discover printers on an IP Network.

 
 package test.zebra.sdk.discovery.examples;
 
 import java.util.ArrayList;
 import java.util.List;
 
 import com.zebra.sdk.printer.discovery.DiscoveredPrinter;
 import com.zebra.sdk.printer.discovery.DiscoveryException;
 import com.zebra.sdk.printer.discovery.DiscoveryHandler;
 import com.zebra.sdk.printer.discovery.NetworkDiscoverer;
 
 public class NetworkDiscovererExample {
     public static void main(String[] args) {
         DiscoveryHandler discoveryHandler = new DiscoveryHandler() {
             List<DiscoveredPrinter> printers = new ArrayList<DiscoveredPrinter>();
 
             public void foundPrinter(DiscoveredPrinter printer) {
                 printers.add(printer);
             }
 
             public void discoveryFinished() {
                 for (DiscoveredPrinter printer : printers) {
                     System.out.println(printer);
                 }
                 System.out.println("Discovered " + printers.size() + " printers.");
             }
 
             public void discoveryError(String message) {
                 System.out.println("An error occurred during discovery : " + message);
             }
         };
         try {
             System.out.println("Starting printer discovery.");
             NetworkDiscoverer.findPrinters(discoveryHandler);
         } catch (DiscoveryException e) {
             e.printStackTrace();
         }
     }
 }
 
 

Method Summary

Methods

Modifier and Type	Method and Description
static void	directedBroadcast(DiscoveryHandler discoveryHandler, String ipAddress) Sends a directed broadcast discovery packet to the subnet specified by ipAddress.
static void	directedBroadcast(DiscoveryHandler discoveryHandler, String ipAddress, int waitForResponsesTimeout) Sends a directed broadcast discovery packet to the subnet specified by ipAddress.
static void	findPrinters(DiscoveryHandler discoveryHandler) This method will search the network using a combination of discovery methods to find printers on the network.
static void	findPrinters(DiscoveryHandler discoveryHandler, List<String> printersToFind) Sends a discovery request to the list of printer DNS names or IPs in printersToFind.
static void	findPrinters(DiscoveryHandler discoveryHandler, List<String> printersToFind, int waitForResponsesTimeout) Sends a discovery request to the list of printer DNS names or IPs in printersToFind.
static void	localBroadcast(DiscoveryHandler discoveryHandler) Sends a local broadcast packet.
static void	localBroadcast(DiscoveryHandler discoveryHandler, int waitForResponsesTimeout) Sends a local broadcast packet.
static void	multicast(DiscoveryHandler discoveryHandler, int hops) Sends a multicast discovery packet.
static void	multicast(DiscoveryHandler discoveryHandler, int hops, int waitForResponsesTimeout) Sends a multicast discovery packet.
static void	subnetSearch(DiscoveryHandler discoveryHandler, String subnetRange) Sends a discovery packet to the IPs specified in the subnetRange.
static void	subnetSearch(DiscoveryHandler discoveryHandler, String subnetRange, int waitForResponsesTimeout) Sends a discovery packet to the IPs specified in the subnetRange.

Methods inherited from class Object

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

Method Detail

subnetSearch

public static void subnetSearch(DiscoveryHandler discoveryHandler,
                String subnetRange)
                         throws DiscoveryException

Sends a discovery packet to the IPs specified in the subnetRange. Subnet searches are defined by the first three subnet octets, followed by a range, such as 192.168.2. This method accepts IP addresses of the form, assuming a subnet of 192.168.2:

• 192.168.2.254 (will send a discovery packet to 192.168.2.254)
• 192.168.2.* (will send a discovery packet for the range 192.168.2.1 - 192.168.2.254)
• 192.168.2.8-* (will send a discovery packet for the range 192.168.2.8 - 192.168.2.254)
• 192.168.2.37-42 (will send a discovery packet for the range 192.168.2.37 - 192.168.2.42)

This method will invoke the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method for each printer that is found during discovery. DiscoveryHandler.discoveryFinished() will be invoked when the discovery is finished and DiscoveryHandler.discoveryError(String) will be invoked when any errors are encountered during discovery. When DiscoveryHandler.discoveryError(String) is invoked, the discovery will be canceled and DiscoveryHandler.discoveryFinished() will not be invoked.

If a printer responds to the discovery request more than once, the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method will only be invoked on the first occurrence.

Parameters:

discoveryHandler - a DiscoveryHandler instance that is used to handle discovery events (e.g. found a printer, errors, discovery finished).

subnetRange - the subnet search range.

Throws:

DiscoveryException - if an error occurs while starting the discovery (errors during discovery will be sent via DiscoveryHandler.discoveryError(String)).

subnetSearch

public static void subnetSearch(DiscoveryHandler discoveryHandler,
                String subnetRange,
                int waitForResponsesTimeout)
                         throws DiscoveryException

Sends a discovery packet to the IPs specified in the subnetRange. This method will wait up to waitForResponsesTimeout milliseconds determining that there are no more discovery responses. Subnet searches are defined by the first three subnet octets, followed by a range, such as 192.168.2. This method accepts IP addresses of the form, assuming a subnet of 192.168.2:

• 192.168.2.254 (will send a discovery packet to 192.168.2.254)
• 192.168.2.* (will send a discovery packet for the range 192.168.2.1 - 192.168.2.254)
• 192.168.2.8-* (will send a discovery packet for the range 192.168.2.8 - 192.168.2.254)
• 192.168.2.37-42 (will send a discovery packet for the range 192.168.2.37 - 192.168.2.42)

This method will invoke the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method for each printer that is found during discovery. DiscoveryHandler.discoveryFinished() will be invoked when the discovery is finished and DiscoveryHandler.discoveryError(String) will be invoked when any errors are encountered during discovery. When DiscoveryHandler.discoveryError(String) is invoked, the discovery will be canceled and DiscoveryHandler.discoveryFinished() will not be invoked.

If a printer responds to the discovery request more than once, the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method will only be invoked on the first occurrence.

Parameters:

discoveryHandler - a DiscoveryHandler instance that is used to handle discovery events (e.g. found a printer, errors, discovery finished).

subnetRange - the subnet search range.

waitForResponsesTimeout - time to wait, in milliseconds, before determining that there are no more discovery responses.

Throws:

DiscoveryException - if an error occurs while starting the discovery (errors during discovery will be sent via DiscoveryHandler.discoveryError(String)).

directedBroadcast

public static void directedBroadcast(DiscoveryHandler discoveryHandler,
                     String ipAddress)
                              throws DiscoveryException

Sends a directed broadcast discovery packet to the subnet specified by ipAddress. Directed broadcasts are defined by the first three subnet octets, followed by 255, such as 192.168.2.255. This method accepts IP addresses of the form, assuming a subnet of 192.168.2:

• 192.168.2.255
• 192.168.2.1 (last octet will be replaced with 255)
• 192.168.2 (will append 255 for the last octet)
• 192.168.2. (will append 255 for the last octet)

This method will invoke the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method for each printer that is found during discovery. DiscoveryHandler.discoveryFinished() will be invoked when the discovery is finished and DiscoveryHandler.discoveryError(String) will be invoked when any errors are encountered during discovery. When DiscoveryHandler.discoveryError(String) is invoked, the discovery will be canceled and DiscoveryHandler.discoveryFinished() will not be invoked.

If a printer responds to the discovery request more than once, the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method will only be invoked on the first occurrence.

Parameters:

discoveryHandler - a DiscoveryHandler instance that is used to handle discovery events (e.g. found a printer, errors, discovery finished).

ipAddress - the IP address of the subnet.

Throws:

DiscoveryException - if an error occurs while starting the discovery (errors during discovery will be sent via DiscoveryHandler.discoveryError(String)).

directedBroadcast

public static void directedBroadcast(DiscoveryHandler discoveryHandler,
                     String ipAddress,
                     int waitForResponsesTimeout)
                              throws DiscoveryException

Sends a directed broadcast discovery packet to the subnet specified by ipAddress. This method will wait up to waitForResponsesTimeout milliseconds determining that there are no more discovery responses. Directed broadcasts are defined by the first three subnet octets, followed by 255, such as 192.168.2.255. This method accepts IP addresses of the form, assuming a subnet of 192.168.2:

• 192.168.2.255
• 192.168.2.1 (last octet will be replaced with 255)
• 192.168.2 (will append 255 for the last octet)
• 192.168.2. (will append 255 for the last octet)

This method will invoke the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method for each printer that is found during discovery. DiscoveryHandler.discoveryFinished() will be invoked will be invoked when the discovery is finished and DiscoveryHandler.discoveryError(String) when any errors are encountered during discovery. When DiscoveryHandler.discoveryError(String) is invoked, the discovery will be canceled and DiscoveryHandler.discoveryFinished() will not be invoked.

If a printer responds to the discovery request more than once, the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method will only be invoked on the first occurrence.

Parameters:

discoveryHandler - a DiscoveryHandler instance that is used to handle discovery events (e.g. found a printer, errors, discovery finished).

ipAddress - the IP address of the subnet.

waitForResponsesTimeout - time to wait, in milliseconds, before determining that there are no more discovery responses.

Throws:

DiscoveryException - if an error occurs while starting the discovery (errors during discovery will be sent via DiscoveryHandler.discoveryError(String)).

localBroadcast

public static void localBroadcast(DiscoveryHandler discoveryHandler)
                           throws DiscoveryException

Sends a local broadcast packet. This method will invoke the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method for each printer that is found during discovery. DiscoveryHandler.discoveryFinished() will be invoked when the discovery is finished and DiscoveryHandler.discoveryError(String) will be invoked when any errors are encountered during discovery. When DiscoveryHandler.discoveryError(String) is invoked, the discovery will be canceled and DiscoveryHandler.discoveryFinished() will not be invoked.

If a printer responds to the discovery request more than once, the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method will only be invoked on the first occurrence.

Parameters:

discoveryHandler - a DiscoveryHandler instance that is used to handle discovery events (e.g. found a printer, errors, discovery finished).

Throws:

DiscoveryException - if an error occurs while starting the discovery (errors during discovery will be sent via DiscoveryHandler.discoveryError(String)).

localBroadcast

public static void localBroadcast(DiscoveryHandler discoveryHandler,
                  int waitForResponsesTimeout)
                           throws DiscoveryException

Sends a local broadcast packet. This method will wait up to waitForResponsesTimeout milliseconds determining that there are no more discovery responses.

This method will invoke the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method for each printer that is found during discovery. DiscoveryHandler.discoveryFinished() will be invoked when the discovery is finished and DiscoveryHandler.discoveryError(String) will be invoked when any errors are encountered during discovery. When DiscoveryHandler.discoveryError(String) is invoked, the discovery will be canceled and DiscoveryHandler.discoveryFinished() will not be invoked.

If a printer responds to the discovery request more than once, the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method will only be invoked on the first occurrence.

Parameters:

discoveryHandler - a DiscoveryHandler instance that is used to handle discovery events (e.g. found a printer, errors, discovery finished).

waitForResponsesTimeout - time to wait, in milliseconds, before determining that there are no more discovery responses.

Throws:

DiscoveryException - if an error occurs while starting the discovery (errors during discovery will be sent via DiscoveryHandler.discoveryError(String)).

multicast

public static void multicast(DiscoveryHandler discoveryHandler,
             int hops)
                      throws DiscoveryException

Sends a multicast discovery packet. This method will invoke the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method for each printer that is found during discovery. DiscoveryHandler.discoveryFinished() will be invoked when the discovery is finished and DiscoveryHandler.discoveryError(String) will be invoked when any errors are encountered during discovery. When DiscoveryHandler.discoveryError(String) is invoked, the discovery will be canceled and DiscoveryHandler.discoveryFinished() will not be invoked.

If a printer responds to the discovery request more than once, the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method will only be invoked on the first occurrence.

Note: For Android users : some extra code is required to obtain a multicast lock. See the example in multicast(DiscoveryHandler, int, int):

Parameters:

discoveryHandler - a DiscoveryHandler instance that is used to handle discovery events (e.g. found a printer, errors, discovery finished).

hops - number of hops.

Throws:

DiscoveryException - if an error occurs while starting the discovery (errors during discovery will be sent via DiscoveryHandler.discoveryError(String)).

multicast

public static void multicast(DiscoveryHandler discoveryHandler,
             int hops,
             int waitForResponsesTimeout)
                      throws DiscoveryException

Sends a multicast discovery packet. This method will wait up to waitForResponsesTimeout milliseconds determining that there are no more discovery responses.

This method will invoke the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method for each printer that is found during discovery. DiscoveryHandler.discoveryFinished() will be invoked when the discovery is finished and DiscoveryHandler.discoveryError(String) will be invoked when any errors are encountered during discovery. When DiscoveryHandler.discoveryError(String) is invoked, the discovery will be canceled and DiscoveryHandler.discoveryFinished() will not be invoked.

If a printer responds to the discovery request more than once, the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method will only be invoked on the first occurrence.

Note: For Android users : some extra code is required to obtain a multicast lock. See following example:

package test.zebra.sdk.printer.discovery.examples;
 
 import android.app.Activity;
 import android.content.Context;
 import android.net.wifi.WifiManager;
 import android.net.wifi.WifiManager.MulticastLock;
 import android.os.Bundle;
 
 import com.zebra.sdk.printer.discovery.DiscoveredPrinter;
 import com.zebra.sdk.printer.discovery.DiscoveryException;
 import com.zebra.sdk.printer.discovery.DiscoveryHandler;
 import com.zebra.sdk.printer.discovery.NetworkDiscoverer;
 
 public class NetworkDiscovererAndroidMulticastExample extends Activity {
 
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
         int multicastHops = 5;
         WifiManager wifi = (WifiManager) getSystemService(Context.WIFI_SERVICE);
         MulticastLock lock = wifi.createMulticastLock("wifi_multicast_lock");
         lock.setReferenceCounted(true);
         lock.acquire();
         try {
             NetworkDiscoverer.multicast(new DiscoveryHandler() {
                 public void foundPrinter(DiscoveredPrinter printer) {
                     System.out.println("Found a printer with address : " + printer.address);
                 }
 
                 public void discoveryFinished() {
                     System.out.println("Discovery finished");
                 }
 
                 public void discoveryError(String message) {
                     System.out.println("Discovery error! - " + message);
                 }
             }, multicastHops);
         } catch (DiscoveryException e) {
             e.printStackTrace();
         }
         lock.release();
     }
 }
 

Parameters:

discoveryHandler - a DiscoveryHandler instance that is used to handle discovery events (e.g. found a printer, errors, discovery finished).

hops - number of hops.

waitForResponsesTimeout - time to wait, in milliseconds, before determining that there are no more discovery responses.

Throws:

DiscoveryException - if an error occurs while starting the discovery (errors during discovery will be sent via DiscoveryHandler.discoveryError(String)).

findPrinters

public static void findPrinters(DiscoveryHandler discoveryHandler)
                         throws DiscoveryException

This method will search the network using a combination of discovery methods to find printers on the network. This is a convenience method that can be used as an alternative to the other discovery methods (e.g. multicast)

This method will invoke the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method for each printer that is found during discovery. DiscoveryHandler.discoveryFinished() will be invoked when the discovery is finished and DiscoveryHandler.discoveryError(String) will be invoked when any errors are encountered during discovery. When DiscoveryHandler.discoveryError(String) is invoked, the discovery will be canceled and DiscoveryHandler.discoveryFinished() will not be invoked.

If a printer responds to the discovery request more than once, the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method will only be invoked on the first occurrence.

Parameters:

discoveryHandler - a DiscoveryHandler instance that is used to handle discovery events (e.g. found a printer, errors, discovery finished).

Throws:

DiscoveryException - if an error occurs while starting the discovery (errors during discovery will be sent via DiscoveryHandler.discoveryError(String)).

findPrinters

public static void findPrinters(DiscoveryHandler discoveryHandler,
                List<String> printersToFind)
                         throws DiscoveryException

Sends a discovery request to the list of printer DNS names or IPs in printersToFind. This method will invoke the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method for each printer that is found during discovery. DiscoveryHandler.discoveryFinished() will be invoked when the discovery is finished and DiscoveryHandler.discoveryError(String) will be invoked when any errors are encountered during discovery.
If a printer responds to the discovery request more than once, the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method will only be invoked on the first occurrence.

Parameters:

discoveryHandler - a DiscoveryHandler instance that is used to handle discovery events (e.g. found a printer, errors, discovery finished).

printersToFind - A list of IP addresses or DNS names for the printers to be discovered.

Throws:

DiscoveryException - if an error occurs while starting the discovery (errors during discovery will be sent via DiscoveryHandler.discoveryError(String)).

findPrinters

public static void findPrinters(DiscoveryHandler discoveryHandler,
                List<String> printersToFind,
                int waitForResponsesTimeout)
                         throws DiscoveryException

Sends a discovery request to the list of printer DNS names or IPs in printersToFind. This method will invoke the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method for each printer that is found during discovery. DiscoveryHandler.discoveryFinished() will be invoked when the discovery is finished and DiscoveryHandler.discoveryError(String) will be invoked when any errors are encountered during discovery.
If a printer responds to the discovery request more than once, the DiscoveryHandler.foundPrinter(DiscoveredPrinter) method will only be invoked on the first occurrence.

Parameters:

discoveryHandler - a DiscoveryHandler instance that is used to handle discovery events (e.g. found a printer, errors, discovery finished).

printersToFind - A list of IP addresses or DNS names for the printers to be discovered.

waitForResponsesTimeout - time to wait, in milliseconds, before determining that there are no more discovery responses.

Throws:

DiscoveryException - if an error occurs while starting the discovery (errors during discovery will be sent via DiscoveryHandler.discoveryError(String)).