001// Copyright 2004, 2005 The Apache Software Foundation 002// 003// Licensed under the Apache License, Version 2.0 (the "License"); 004// you may not use this file except in compliance with the License. 005// You may obtain a copy of the License at 006// 007// http://www.apache.org/licenses/LICENSE-2.0 008// 009// Unless required by applicable law or agreed to in writing, software 010// distributed under the License is distributed on an "AS IS" BASIS, 011// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 012// See the License for the specific language governing permissions and 013// limitations under the License. 014 015package org.apache.tapestry.util; 016 017import java.util.List; 018 019/** 020 * An interface that defines an object that can store named propertys. The names 021 * and the properties are Strings. 022 * 023 * @author Howard Lewis Ship 024 * 025 **/ 026 027public interface IPropertyHolder 028{ 029 /** 030 * Returns a List of Strings, the names of all 031 * properties held by the receiver. May return an empty list. 032 * The List is sorted alphabetically. The List may be modified 033 * without affecting this property holder. 034 * 035 * <p>Prior to release 2.2, this method returned Collection. 036 * 037 **/ 038 039 public List getPropertyNames(); 040 041 /** 042 * Sets a named property. The new value replaces the existing value, if any. 043 * Setting a property to null is the same as removing the property. 044 * 045 **/ 046 047 public void setProperty(String name, String value); 048 049 /** 050 * Removes the named property, if present. 051 * 052 **/ 053 054 public void removeProperty(String name); 055 056 /** 057 * Retrieves the named property, or null if the property is not defined. 058 * 059 **/ 060 061 public String getProperty(String name); 062}