001// Copyright 2006, 2007 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.tapestry5.ioc; 016 017/** 018 * Provides access to a messages catalog, a set of properties files that provide localized messages for a particular 019 * locale. The message catalog consists of keys and values and follows the semantics of a Java {@link 020 * java.util.ResourceBundle} with some changes. 021 */ 022public interface Messages 023{ 024 /** 025 * Returns true if the bundle contains the named key. 026 */ 027 boolean contains(String key); 028 029 /** 030 * Returns the localized message for the given key. If catalog does not contain such a key, then a modified version 031 * of the key is returned (converted to upper case and enclosed in brackets). 032 * 033 * @param key 034 * @return localized message for key, or placeholder 035 */ 036 String get(String key); 037 038 /** 039 * Returns a formatter for the message, which can be used to substitute arguments (as per {@link 040 * java.util.Formatter}). 041 * 042 * @param key 043 * @return formattable object 044 */ 045 MessageFormatter getFormatter(String key); 046 047 /** 048 * Convienience for accessing a formatter and formatting a localized message with arguments. 049 */ 050 051 String format(String key, Object... args); 052}