com.lightstreamer.javameclient.midp

Interface ConnectionProvider

public interface ConnectionProvider

Used by LSClient to obtain Connection instances. An instance of an implemented class may be passed to an LSClient instance through LSClient.setConnectionProvider(ConnectionProvider) so that it will be used in place of the default one.

Field Summary

Fields

Modifier and Type	Field and Description
static int	TYPE_HTTP Constant used to specify that a HttpConnection is expected.
static int	TYPE_SOCKET Constant used to specify that a SocketConnection is expected.

Method Summary

Modifier and Type	Method and Description
java.lang.Object	clone() Clone method used internally to spread the provider inside the various parts of the library.
javax.microedition.io.Connection	getNextConnection(java.lang.String url, boolean secure) Provider method used to obtain a new Connection instance to be used to connect to Lightstreamer server.
boolean	hasConnections() Test method that returns true if this provider is still able to provide a new type of Connection in response of a getNextConnection(String, boolean) call for a certain type parameter value.
void	rebuild() Method used to reset the current instance.
void	setType(int type) Defines the type of ConnectionProvider.
void	wasSuccessful() Called after the getNextConnection(String, boolean) method to inform the ConnectionProvider that the last given Connection was successfully used by the library.

Field Detail

TYPE_HTTP

static final int TYPE_HTTP

Constant used to specify that a HttpConnection is expected.

See Also:

Constant Field Values

TYPE_SOCKET

static final int TYPE_SOCKET

Constant used to specify that a SocketConnection is expected.

See Also:

Constant Field Values

Method Detail

setType

void setType(int type)

Defines the type of ConnectionProvider. A TYPE_HTTP ConnectionProvider must provide instances of HttpConnection while a TYPE_SOCKET ConnectionProvider must provide instances of SocketConnection.

Parameters:

type - Flag specifying the type of the expected Connection, TYPE_HTTP for HttpConnection or TYPE_SOCKET for SocketConnection.

rebuild

void rebuild()

Method used to reset the current instance. Until a new call to this method is performed this instance should not return the same type of Connection object two times in response of two getNextConnection(String, boolean) calls using the same type parameter value.

wasSuccessful

void wasSuccessful()

Called after the getNextConnection(String, boolean) method to inform the ConnectionProvider that the last given Connection was successfully used by the library. If rebuild() is called two times without this method being called, then the library wasn't able to connect to the server at all with the given Connection(s). This may happen if there is no network availability or, if the Connection was constructed in a wrong way in respect with the current environment. If the active ConnectionProvider is substituted while the library is connected/connecting this method may be called before any getNextConnection call. In that case it has to be ignored.

hasConnections

boolean hasConnections()

Test method that returns true if this provider is still able to provide a new type of Connection in response of a getNextConnection(String, boolean) call for a certain type parameter value.

Returns:

true if a new call to getNextConnection is permitted, false otherwise.

getNextConnection

javax.microedition.io.Connection getNextConnection(java.lang.String url,
                                                   boolean secure)
                                            throws java.io.IOException

Provider method used to obtain a new Connection instance to be used to connect to Lightstreamer server. Note that this method may be called two consecutive times from two different threads in case the first one hangs without response. The implementation should avoid locks on blocking calls.

Parameters:

url - The url to be opened.

secure - If true a new secure connection is needed. Info related to the secure/non-secure nature of the connection can also be extracted from the url parameter.

Returns:

a Connection object.

Throws:

java.io.IOException - If some kind of I/O error occurs.

clone

java.lang.Object clone()

Clone method used internally to spread the provider inside the various parts of the library. Note that the type of a cloned instance may be changed after its creation so that it is not necessary to clone the instance type.

Returns:

a clone of this ConnectionProvider instance.