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 */ 017package org.apache.camel.util; 018 019import java.util.regex.Matcher; 020import java.util.regex.Pattern; 021 022/** 023 * A resolver for file paths that supports resolving with system and environment properties. 024 */ 025public final class FilePathResolver { 026 027 // must be non greedy patterns 028 private static final Pattern ENV_PATTERN = Pattern.compile("\\$\\{env:(.*?)\\}", Pattern.DOTALL); 029 private static final Pattern SYS_PATTERN = Pattern.compile("\\$\\{(.*?)\\}", Pattern.DOTALL); 030 031 private FilePathResolver() { 032 } 033 034 /** 035 * Resolves the path. 036 * <p/> 037 * The pattern is: 038 * <ul> 039 * <li><tt>${env.key}</tt> for environment variables.</li> 040 * <li><tt>${key}</tt> for JVM system properties.</li> 041 * </ul> 042 * For example: <tt>${env.KARAF_HOME}/data/logs</tt> 043 * 044 * @param path the path 045 * @return the resolved path 046 * @throws IllegalArgumentException is thrown if system property / environment not found 047 */ 048 public static String resolvePath(String path) throws IllegalArgumentException { 049 Matcher matcher = ENV_PATTERN.matcher(path); 050 while (matcher.find()) { 051 String key = matcher.group(1); 052 String value = System.getenv(key); 053 if (ObjectHelper.isEmpty(value)) { 054 throw new IllegalArgumentException("Cannot find system environment with key: " + key); 055 } 056 // must quote the replacement to have it work as literal replacement 057 value = Matcher.quoteReplacement(value); 058 path = matcher.replaceFirst(value); 059 // must match again as location is changed 060 matcher = ENV_PATTERN.matcher(path); 061 } 062 063 matcher = SYS_PATTERN.matcher(path); 064 while (matcher.find()) { 065 String key = matcher.group(1); 066 String value = System.getProperty(key); 067 if (ObjectHelper.isEmpty(value)) { 068 throw new IllegalArgumentException("Cannot find JVM system property with key: " + key); 069 } 070 // must quote the replacement to have it work as literal replacement 071 value = Matcher.quoteReplacement(value); 072 path = matcher.replaceFirst(value); 073 // must match again as location is changed 074 matcher = SYS_PATTERN.matcher(path); 075 } 076 077 return path; 078 } 079 080}