| // Copyright 2006, 2007 The Apache Software Foundation |
| // |
| // 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 org.apache.tapestry5.ioc.services; |
| |
| import org.apache.tapestry5.ioc.annotations.Value; |
| |
| /** |
| * Used to manage <em>symbols</em>, configuration properties whose value is evaluated at runtime. Symbols use the Ant |
| * syntax: <code>${foo.bar.baz}</code> where <code>foo.bar.baz</code> is the name of the symbol. The symbol may appear |
| * inside annotation, such as {@link Value}. Values for symbols are provided by {@link SymbolProvider}. |
| */ |
| public interface SymbolSource |
| { |
| /** |
| * Expands the value for a particular symbol. This may involve recursive expansion, if the immediate value for the |
| * symbol itself contains symbols. |
| * |
| * @param symbolName |
| * @return the expanded string |
| * @throws RuntimeException if the symbol name can not be expanded (no {@link SymbolProvider} can provide its |
| * value), or if an expansion is directly or indirectly recursive |
| */ |
| String valueForSymbol(String symbolName); |
| |
| /** |
| * Given an input string that <em>may</em> contain symbols, returns the string with any and all symbols fully |
| * expanded. |
| * |
| * @param input |
| * @return expanded input |
| */ |
| String expandSymbols(String input); |
| } |