logentry.java

OSGI这是一个中间件,与UPNP齐名,是用于移植到嵌入式平台之上

/*
 * $Header: /home/wistrand/cvs/knopflerfish.org/osgi/bundles/log/src/org/osgi/service/log/LogEntry.java,v 1.1.1.1 2004/03/05 20:35:13 wistrand Exp $
 *
 * Copyright (c) The Open Services Gateway Initiative (2000, 2002).
 * All Rights Reserved.
 *
 * Implementation of certain elements of the Open Services Gateway Initiative
 * (OSGI) Specification may be subject to third party intellectual property
 * rights, including without limitation, patent rights (such a third party may
 * or may not be a member of OSGi). OSGi is not responsible and shall not be
 * held responsible in any manner for identifying or failing to identify any or
 * all such third party intellectual property rights.
 *
 * This document and the information contained herein are provided on an "AS
 * IS" basis and OSGI DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
 * BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION HEREIN WILL
 * NOT INFRINGE ANY RIGHTS AND ANY IMPLIED WARRANTIES OF MERCHANTABILITY OR
 * FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT WILL OSGI BE LIABLE FOR ANY
 * LOSS OF PROFITS, LOSS OF BUSINESS, LOSS OF USE OF DATA, INTERRUPTION OF
 * BUSINESS, OR FOR DIRECT, INDIRECT, SPECIAL OR EXEMPLARY, INCIDENTIAL,
 * PUNITIVE OR CONSEQUENTIAL DAMAGES OF ANY KIND IN CONNECTION WITH THIS
 * DOCUMENT OR THE INFORMATION CONTAINED HEREIN, EVEN IF ADVISED OF THE
 * POSSIBILITY OF SUCH LOSS OR DAMAGE.
 *
 * All Company, brand and product names may be trademarks that are the sole
 * property of their respective owners. All rights reserved.
 */

package org.osgi.service.log;

import org.osgi.framework.Bundle;
import org.osgi.framework.ServiceReference;

/**
 * Provides methods to access the information contained in an individual Log
 * Service log entry.
 * 
 * <p>
 * A <tt>LogEntry</tt> object may be acquired from the
 * <tt>LogReaderService.getLog</tt> method or by registering a
 * <tt>LogListener</tt> object.
 * 
 * @version $Revision: 1.1.1.1 $
 * @author Open Services Gateway Initiative
 * @see LogReaderService#getLog
 * @see LogListener
 */
public abstract interface LogEntry {
    /**
     * Returns the bundle that created this <tt>LogEntry</tt> object.
     * 
     * @return The bundle that created this <tt>LogEntry</tt> object;
     *         <tt>null</tt> if no bundle is associated with this
     *         <tt>LogEntry</tt> object.
     */
    public abstract Bundle getBundle();

    /**
     * Returns the <tt>ServiceReference</tt> object for the service associated
     * with this <tt>LogEntry</tt> object.
     * 
     * @return <tt>ServiceReference</tt> object for the service associated
     *         with this <tt>LogEntry</tt> object; <tt>null</tt> if no
     *         <tt>ServiceReference</tt> object was provided.
     */
    public abstract ServiceReference getServiceReference();

    /**
     * Returns the severity level of this <tt>LogEntry</tt> object.
     * 
     * <p>
     * This is one of the severity levels defined by the <tt>LogService</tt>
     * interface.
     * 
     * @return Severity level of this <tt>LogEntry</tt> object.
     * 
     * @see LogService#LOG_ERROR
     * @see LogService#LOG_WARNING
     * @see LogService#LOG_INFO
     * @see LogService#LOG_DEBUG
     */
    public abstract int getLevel();

    /**
     * Returns the human readable message associated with this <tt>LogEntry</tt>
     * object.
     * 
     * @return <tt>String</tt> containing the message associated with this
     *         <tt>LogEntry</tt> object.
     */
    public abstract String getMessage();

    /**
     * Returns the exception object associated with this <tt>LogEntry</tt>
     * object.
     * 
     * <p>
     * In some implementations, the returned exception may not be the original
     * exception. To avoid references to a bundle defined exception class, thus
     * preventing an uninstalled bundle from being garbage collected, the Log
     * Service may return an exception object of an implementation defined
     * Throwable subclass. The returned object will attempt to provide as much
     * information as possible from the original exception object such as the
     * message and stack trace.
     * 
     * @return <tt>Throwable</tt> object of the exception associated with this
     *         <tt>LogEntry</tt>; <tt>null</tt> if no exception is
     *         associated with this <tt>LogEntry</tt> objcet.
     */
    public abstract Throwable getException();

    /**
     * Returns the value of <tt>currentTimeMillis()</tt> at the time this
     * <tt>LogEntry</tt> object was created.
     * 
     * @return The system time in milliseconds when this <tt>LogEntry</tt>
     *         object was created.
     * @see "System.currentTimeMillis()"
     */
    public abstract long getTime();
}