001 /** 002 * Licensed to the Apache Software Foundation (ASF) under one or more 003 * contributor license agreements. See the NOTICE file distributed with 004 * this work for additional information regarding copyright ownership. 005 * The ASF licenses this file to You under the Apache License, Version 2.0 006 * (the "License"); you may not use this file except in compliance with 007 * the License. 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 */ 017 package org.apache.xbean.kernel; 018 019 /** 020 * The immutable unique name of a service. A proper implementation of ServiceName must have a correct implementation of 021 * equals and hashCode. A ServiceName should have one constructor that takes a single String and the toString method 022 * should return a String that can be used in the String constructor. This means the following code should work: 023 * <p><blockquote><pre> 024 * Constructor constructor = serviceName.getClass().getConstructor(new Class[] {String.class}); 025 * ServiceName name = constructor.newInstance(new Object[] {serviceName.toString()}); 026 * </pre></blockquote> 027 * 028 * @author Dain Sundstrom 029 * @version $Id$ 030 * @since 2.0 031 */ 032 public interface ServiceName { 033 /** 034 * A service name must properly implement hashCode. For example, 035 * <p><blockquote><pre> 036 * public int hashCode() { 037 * int result = 17; 038 * result = 37 * result + integer; 039 * result = 37 * result + (object == null ? 0 : object.hashCode()); 040 * return result; 041 * } 042 * </pre></blockquote> 043 * 044 * @return the hash code 045 */ 046 int hashCode(); 047 048 /** 049 * A service name must property implement equals. For example, 050 * <p><blockquote><pre> 051 * public boolean equals(Object obj) { 052 * if (!(obj instanceof MyServiceName)) { 053 * return false; 054 * } 055 * MyServiceName name = (MyServiceName) obj; 056 * return integer == name.integer && 057 * (object == null ? name.object == null : object.equals(name.object)); 058 * } 059 * </pre></blockquote> 060 * 061 * @param object some object 062 * @return true if the object is equivalent to this service name; false otherwise 063 */ 064 boolean equals(Object object); 065 066 /** 067 * A service name should return a string from toString that can be used in a String constructor. 068 * 069 * @return the connonical form of this name 070 */ 071 String toString(); 072 }