org.osgi.service.log
Interface LogReaderService

public interface LogReaderService

Provides methods to retrieve LogEntry objects from the log.

There are two ways to retrieve LogEntry objects:

• The primary way to retrieve LogEntry objects is to register a LogListener object whose LogListener.logged method will be called for each entry added to the log.
• To retrieve past LogEntry objects, the getLog method can be called which will return an Enumeration of all LogEntry objects in the log.

See Also:

LogEntry, LogListener, LogListener.logged(LogEntry)

ThreadSafe

Method Summary

void	addLogListener(LogListener listener) Subscribes to LogEntry objects.
java.util.Enumeration	getLog() Returns an Enumeration of all LogEntry objects in the log.
void	removeLogListener(LogListener listener) Unsubscribes to LogEntry objects.

Method Detail

addLogListener

void addLogListener(LogListener listener)

Subscribes to LogEntry objects.

This method registers a LogListener object with the Log Reader Service. The LogListener.logged(LogEntry) method will be called for each LogEntry object placed into the log.

When a bundle which registers a LogListener object is stopped or otherwise releases the Log Reader Service, the Log Reader Service must remove all of the bundle's listeners.

If this Log Reader Service's list of listeners already contains a listener l such that (l==listener), this method does nothing.

Parameters:

listener - A LogListener object to register; the LogListener object is used to receive LogEntry objects.

See Also:

LogListener, LogEntry, LogListener.logged(LogEntry)

removeLogListener

void removeLogListener(LogListener listener)

Unsubscribes to LogEntry objects.

This method unregisters a LogListener object from the Log Reader Service.

If listener is not contained in this Log Reader Service's list of listeners, this method does nothing.

Parameters:

listener - A LogListener object to unregister.

See Also:

LogListener

getLog

java.util.Enumeration getLog()

Returns an Enumeration of all LogEntry objects in the log.

Each element of the enumeration is a LogEntry object, ordered with the most recent entry first. Whether the enumeration is of all LogEntry objects since the Log Service was started or some recent past is implementation-specific. Also implementation-specific is whether informational and debug LogEntry objects are included in the enumeration.

Returns:

An Enumeration of all LogEntry objects in the log.