001// Copyright 2006 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.internal.services;
016
017import org.apache.tapestry5.ioc.services.SymbolProvider;
018
019/**
020 * Obtains symbol values from JVM System properties. This implementation is usually ordered first, so that explicit
021 * overrides, provided as JVM system properties, can take effect.
022 */
023public class SystemPropertiesSymbolProvider implements SymbolProvider
024{
025    @Override
026    public String valueForSymbol(String symbolName)
027    {
028        return System.getProperty(symbolName);
029    }
030}