Java tutorial
/* * Copyright 2007 Yusuke Yamamoto * * Licensed 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 twitter4j.auth; import twitter4j.HttpRequest; import java.io.ObjectStreamException; /** * An interface represents credentials. * * @author Yusuke Yamamoto - yusuke at mac.com */ public class NullAuthorization implements Authorization, java.io.Serializable { private static final long serialVersionUID = -7704668493278727510L; private static final NullAuthorization SINGLETON = new NullAuthorization(); private NullAuthorization() { } public static NullAuthorization getInstance() { return SINGLETON; } @Override public String getAuthorizationHeader(HttpRequest req) { return null; } @Override public boolean isEnabled() { return false; } @Override public boolean equals(Object o) { return SINGLETON == o; } @Override public String toString() { return "NullAuthentication{SINGLETON}"; } private Object readResolve() throws ObjectStreamException { return SINGLETON; } }