/* * Licensed to the Apache Software Foundation (ASF) under one or more * contributor license agreements.  See the NOTICE file distributed with * this work for additional information regarding copyright ownership. * The ASF licenses this file to You under the Apache License, Version 2.0 * (the "License"); you may not use this file except in compliance with * the License.  You may obtain a copy of the License at *  *      http://www.apache.org/licenses/LICENSE-2.0 *  * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */package org.apache.log4j.helpers;import org.apache.log4j.spi.AppenderAttachable;import org.apache.log4j.spi.LoggingEvent;import org.apache.log4j.Appender;import java.util.Vector;import java.util.Enumeration;/**   A straightforward implementation of the {@link AppenderAttachable}   interface.   @author Ceki G&uuml;lc&uuml;   @since version 0.9.1 */public class AppenderAttachableImpl implements AppenderAttachable {    /** Array of appenders. */  protected Vector  appenderList;  /**     Attach an appender. If the appender is already in the list in     won't be added again.  */  public  void addAppender(Appender newAppender) {    // Null values for newAppender parameter are strictly forbidden.    if(newAppender == null)      return;        if(appenderList == null) {      appenderList = new Vector(1);    }    if(!appenderList.contains(newAppender))      appenderList.addElement(newAppender);  }  /**     Call the <code>doAppend</code> method on all attached appenders.  */  public  int appendLoopOnAppenders(LoggingEvent event) {    int size = 0;    Appender appender;    if(appenderList != null) {      size = appenderList.size();      for(int i = 0; i < size; i++) {	appender = (Appender) appenderList.elementAt(i);	appender.doAppend(event);      }    }        return size;  }  /**     Get all attached appenders as an Enumeration. If there are no     attached appenders <code>null</code> is returned.          @return Enumeration An enumeration of attached appenders.   */  public  Enumeration getAllAppenders() {    if(appenderList == null)      return null;    else       return appenderList.elements();      }  /**     Look for an attached appender named as <code>name</code>.     <p>Return the appender with that name if in the list. Return null     otherwise.          */  public  Appender getAppender(String name) {     if(appenderList == null || name == null)      return null;     int size = appenderList.size();     Appender appender;     for(int i = 0; i < size; i++) {       appender = (Appender) appenderList.elementAt(i);       if(name.equals(appender.getName()))	  return appender;     }     return null;      }  /**     Returns <code>true</code> if the specified appender is in the     list of attached appenders, <code>false</code> otherwise.     @since 1.2 */  public   boolean isAttached(Appender appender) {    if(appenderList == null || appender == null)      return false;     int size = appenderList.size();     Appender a;     for(int i = 0; i < size; i++) {       a  = (Appender) appenderList.elementAt(i);       if(a == appender)	  return true;     }     return false;      }  /**   * Remove and close all previously attached appenders.   * */  public  void removeAllAppenders() {    if(appenderList != null) {      int len = appenderList.size();            for(int i = 0; i < len; i++) {	Appender a = (Appender) appenderList.elementAt(i);	a.close();      }      appenderList.removeAllElements();      appenderList = null;          }  }  /**     Remove the appender passed as parameter form the list of attached     appenders.  */  public  void removeAppender(Appender appender) {    if(appender == null || appenderList == null)       return;    appenderList.removeElement(appender);      } /**    Remove the appender with the name passed as parameter form the    list of appenders.    */  public  void removeAppender(String name) {    if(name == null || appenderList == null) return;    int size = appenderList.size();    for(int i = 0; i < size; i++) {      if(name.equals(((Appender)appenderList.elementAt(i)).getName())) {	 appenderList.removeElementAt(i);	 break;      }    }  }}