001/** 002 * 003 * Copyright 2020-2022 Florian Schmaus 004 * 005 * Licensed under the Apache License, Version 2.0 (the "License"); 006 * you may not use this file except in compliance with the License. 007 * You may obtain a copy of the License at 008 * 009 * http://www.apache.org/licenses/LICENSE-2.0 010 * 011 * Unless required by applicable law or agreed to in writing, software 012 * distributed under the License is distributed on an "AS IS" BASIS, 013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 014 * See the License for the specific language governing permissions and 015 * limitations under the License. 016 */ 017package org.jivesoftware.smack.filter; 018 019import javax.xml.namespace.QName; 020 021import org.jivesoftware.smack.packet.ExtensionElement; 022import org.jivesoftware.smack.packet.Stanza; 023import org.jivesoftware.smack.packet.XmlElement; 024import org.jivesoftware.smack.util.XmppElementUtil; 025 026public class ExtensionElementFilter<E extends ExtensionElement> implements StanzaFilter { 027 028 private final Class<E> extensionElementClass; 029 private final QName extensionElementQName; 030 031 public ExtensionElementFilter(Class<E> extensionElementClass) { 032 this.extensionElementClass = extensionElementClass; 033 extensionElementQName = XmppElementUtil.getQNameFor(extensionElementClass); 034 } 035 036 @Override 037 public final boolean accept(Stanza stanza) { 038 XmlElement extensionElement = stanza.getExtension(extensionElementQName); 039 if (extensionElement == null) { 040 return false; 041 } 042 043 if (!extensionElementClass.isInstance(extensionElement)) { 044 return false; 045 } 046 047 E specificExtensionElement = extensionElementClass.cast(extensionElement); 048 return accept(specificExtensionElement); 049 } 050 051 public boolean accept(E extensionElement) { 052 return true; 053 } 054}