logmanager.java

gcc的组建

  /**
   * Resets the logging configuration by removing all handlers for
   * registered named loggers and setting their level to <code>null</code>.
   * The level of the root logger will be set to <code>Level.INFO</code>.
   *
   * @throws SecurityException if a security manager exists and
   *         the caller is not granted the permission to control
   *         the logging infrastructure.
   */
  public synchronized void reset() throws SecurityException
  {
    /* Throw a SecurityException if the caller does not have the
     * permission to control the logging infrastructure.
     */
    checkAccess();

    properties = new Properties();

    Iterator iter = loggers.values().iterator();
    while (iter.hasNext())
      {
	WeakReference ref;
	Logger logger;

	ref = (WeakReference) iter.next();
	if (ref != null)
	  {
	    logger = (Logger) ref.get();

	    if (logger == null)
	      iter.remove();
	    else if (logger != rootLogger)
	      logger.setLevel(null);
	  }
      }

    rootLogger.setLevel(Level.INFO);
  }

  /**
   * Configures the logging framework by reading a configuration file.
   * The name and location of this file are specified by the system
   * property <code>java.util.logging.config.file</code>.  If this
   * property is not set, the URL
   * "{gnu.classpath.home.url}/logging.properties" is taken, where
   * "{gnu.classpath.home.url}" stands for the value of the system
   * property <code>gnu.classpath.home.url</code>.
   *
   * <p>The task of configuring the framework is then delegated to
   * {@link #readConfiguration(java.io.InputStream)}, which will
   * notify registered listeners after having read the properties.
   *
   * @throws SecurityException if a security manager exists and
   *         the caller is not granted the permission to control
   *         the logging infrastructure, or if the caller is
   *         not granted the permission to read the configuration
   *         file.
   *
   * @throws IOException if there is a problem reading in the
   *         configuration file.
   */
  public synchronized void readConfiguration()
    throws IOException, SecurityException
  {
    String path;
    InputStream inputStream;

    path = System.getProperty("java.util.logging.config.file");
    if ((path == null) || (path.length() == 0))
      {
	String url = (System.getProperty("gnu.classpath.home.url")
	             + "/logging.properties");
	inputStream = new URL(url).openStream();
      }
    else
      inputStream = new java.io.FileInputStream(path);

    try
      {
	readConfiguration(inputStream);
      }
    finally
      {
	/* Close the stream in order to save
	 * resources such as file descriptors.
	 */
	inputStream.close();
      }
  }

  public synchronized void readConfiguration(InputStream inputStream)
    throws IOException, SecurityException
  {
    Properties newProperties;
    Enumeration keys;

    checkAccess();
    newProperties = new Properties();
    newProperties.load(inputStream);
    this.properties = newProperties;
    keys = newProperties.propertyNames();

    while (keys.hasMoreElements())
      {
	String key = ((String) keys.nextElement()).trim();
	String value = newProperties.getProperty(key);

	if (value == null)
	  continue;

	value = value.trim();

	if ("handlers".equals(key))
	  {
	    StringTokenizer tokenizer = new StringTokenizer(value);
	    while (tokenizer.hasMoreTokens())
	      {
		String handlerName = tokenizer.nextToken();
		try
		  {
		    Class handlerClass = Class.forName(handlerName);
		    getLogger("").addHandler((Handler) handlerClass
		                             .newInstance());
		  }
		catch (ClassCastException ex)
		  {
		    System.err.println("[LogManager] class " + handlerName
		                       + " is not subclass of java.util.logging.Handler");
		  }
		catch (Exception ex)
		  {
		    //System.out.println("[LogManager.readConfiguration]"+ex);
		  }
	      }
	  }

	if (key.endsWith(".level"))
	  {
	    String loggerName = key.substring(0, key.length() - 6);
	    Logger logger = getLogger(loggerName);

	    if (logger == null)
	      {
		logger = Logger.getLogger(loggerName);
		addLogger(logger);
	      }
	    try
	      {
		logger.setLevel(Level.parse(value));
	      }
	    catch (Exception _)
	      {
		//System.out.println("[LogManager.readConfiguration] "+_);
	      }
	    continue;
	  }
      }

    /* The API specification does not talk about the
     * property name that is distributed with the
     * PropertyChangeEvent.  With test code, it could
     * be determined that the Sun J2SE 1.4 reference
     * implementation uses null for the property name.
     */
    pcs.firePropertyChange(null, null, null);
  }

  /**
   * Returns the value of a configuration property as a String.
   */
  public synchronized String getProperty(String name)
  {
    if (properties != null)
      return properties.getProperty(name);
    else
      return null;
  }

  /**
   * Returns the value of a configuration property as an integer.
   * This function is a helper used by the Classpath implementation
   * of java.util.logging, it is <em>not</em> specified in the
   * logging API.
   *
   * @param name the name of the configuration property.
   *
   * @param defaultValue the value that will be returned if the
   *        property is not defined, or if its value is not an integer
   *        number.
   */
  static int getIntProperty(String name, int defaultValue)
  {
    try
      {
	return Integer.parseInt(getLogManager().getProperty(name));
      }
    catch (Exception ex)
      {
	return defaultValue;
      }
  }

  /**
   * Returns the value of a configuration property as an integer,
   * provided it is inside the acceptable range.
   * This function is a helper used by the Classpath implementation
   * of java.util.logging, it is <em>not</em> specified in the
   * logging API.
   *
   * @param name the name of the configuration property.
   *
   * @param minValue the lowest acceptable value.
   *
   * @param maxValue the highest acceptable value.
   *
   * @param defaultValue the value that will be returned if the
   *        property is not defined, or if its value is not an integer
   *        number, or if it is less than the minimum value,
   *        or if it is greater than the maximum value.
   */
  static int getIntPropertyClamped(String name, int defaultValue,
                                   int minValue, int maxValue)
  {
    int val = getIntProperty(name, defaultValue);
    if ((val < minValue) || (val > maxValue))
      val = defaultValue;
    return val;
  }

  /**
   * Returns the value of a configuration property as a boolean.
   * This function is a helper used by the Classpath implementation
   * of java.util.logging, it is <em>not</em> specified in the
   * logging API.
   *
   * @param name the name of the configuration property.
   *
   * @param defaultValue the value that will be returned if the
   *        property is not defined, or if its value is neither
   *        <code>"true"</code> nor <code>"false"</code>.
   */
  static boolean getBooleanProperty(String name, boolean defaultValue)
  {
    try
      {
	return (new Boolean(getLogManager().getProperty(name))).booleanValue();
      }
    catch (Exception ex)
      {
	return defaultValue;
      }
  }

  /**
   * Returns the value of a configuration property as a Level.
   * This function is a helper used by the Classpath implementation
   * of java.util.logging, it is <em>not</em> specified in the
   * logging API.
   *
   * @param propertyName the name of the configuration property.
   *
   * @param defaultValue the value that will be returned if the
   *        property is not defined, or if
   *        {@link Level.parse(java.lang.String)} does not like
   *        the property value.
   */
  static Level getLevelProperty(String propertyName, Level defaultValue)
  {
    try
      {
	return Level.parse(getLogManager().getProperty(propertyName));
      }
    catch (Exception ex)
      {
	return defaultValue;
      }
  }

  /**
   * Returns the value of a configuration property as a Class.
   * This function is a helper used by the Classpath implementation
   * of java.util.logging, it is <em>not</em> specified in the
   * logging API.
   *
   * @param propertyName the name of the configuration property.
   *
   * @param defaultValue the value that will be returned if the
   *        property is not defined, or if it does not specify
   *        the name of a loadable class.
   */
  static final Class getClassProperty(String propertyName, Class defaultValue)
  {
    Class usingClass = null;

    try
      {
	String propertyValue = logManager.getProperty(propertyName);
	if (propertyValue != null)
	  usingClass = Class.forName(propertyValue);
	if (usingClass != null)
	  return usingClass;
      }
    catch (Exception _)
      {
      }

    return defaultValue;
  }

  static final Object getInstanceProperty(String propertyName, Class ofClass,
                                          Class defaultClass)
  {
    Class klass = getClassProperty(propertyName, defaultClass);
    if (klass == null)
      return null;

    try
      {
	Object obj = klass.newInstance();
	if (ofClass.isInstance(obj))
	  return obj;
      }
    catch (Exception _)
      {
      }

    if (defaultClass == null)
      return null;

    try
      {
	return defaultClass.newInstance();
      }
    catch (java.lang.InstantiationException ex)
      {
	throw new RuntimeException(ex.getMessage());
      }
    catch (java.lang.IllegalAccessException ex)
      {
	throw new RuntimeException(ex.getMessage());
      }
  }

  /**
   * An instance of <code>LoggingPermission("control")</code>
   * that is shared between calls to <code>checkAccess()</code>.
   */
  private static final LoggingPermission controlPermission = new LoggingPermission("control",
                                                                                   null);

  /**
   * Checks whether the current security context allows changing
   * the configuration of the logging framework.  For the security
   * context to be trusted, it has to be granted
   * a LoggingPermission("control").
   *
   * @throws SecurityException if a security manager exists and
   *         the caller is not granted the permission to control
   *         the logging infrastructure.
   */
  public void checkAccess() throws SecurityException
  {
    SecurityManager sm = System.getSecurityManager();
    if (sm != null)
      sm.checkPermission(controlPermission);
  }

  /**
   * Creates a new instance of a class specified by name.
   *
   * @param className the name of the class of which a new instance
   *        should be created.
   *
   * @param ofClass the class to which the new instance should
   *        be either an instance or an instance of a subclass.
   *        FIXME: This description is just terrible.
   *
   * @return the new instance, or <code>null</code> if
   *         <code>className</code> is <code>null</code>, if no class
   *         with that name could be found, if there was an error
   *         loading that class, or if the constructor of the class
   *         has thrown an exception.
   */
  static final Object createInstance(String className, Class ofClass)
  {
    Class klass;

    if ((className == null) || (className.length() == 0))
      return null;

    try
      {
	klass = Class.forName(className);
	if (! ofClass.isAssignableFrom(klass))
	  return null;

	return klass.newInstance();
      }
    catch (Exception _)
      {
	return null;
      }
    catch (java.lang.LinkageError _)
      {
	return null;
      }
  }
}