| 1 | package org.apache.velocity.texen.util; |
| 2 | |
| 3 | /* |
| 4 | * Copyright 2001,2004 The Apache Software Foundation. |
| 5 | * |
| 6 | * Licensed under the Apache License, Version 2.0 (the "License"); |
| 7 | * you may not use this file except in compliance with the License. |
| 8 | * You may obtain a copy of the License at |
| 9 | * |
| 10 | * http://www.apache.org/licenses/LICENSE-2.0 |
| 11 | * |
| 12 | * Unless required by applicable law or agreed to in writing, software |
| 13 | * distributed under the License is distributed on an "AS IS" BASIS, |
| 14 | * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 15 | * See the License for the specific language governing permissions and |
| 16 | * limitations under the License. |
| 17 | */ |
| 18 | |
| 19 | import java.io.FileInputStream; |
| 20 | import java.io.InputStream; |
| 21 | import java.io.IOException; |
| 22 | import java.util.Properties; |
| 23 | import java.util.StringTokenizer; |
| 24 | import org.apache.velocity.texen.Generator; |
| 25 | |
| 26 | /** |
| 27 | * A property utility class for the texen text/code generator |
| 28 | * Usually this class is only used from a Velocity context. |
| 29 | * |
| 30 | * @author <a href="mailto:leon@opticode.co.za">Leon Messerschmidt</a> |
| 31 | * @author <a href="mailto:sbailliez@apache.org">Stephane Bailliez</a> |
| 32 | * @version $Id: PropertiesUtil.java,v 1.9.8.1 2004/03/03 23:23:07 geirm Exp $ |
| 33 | */ |
| 34 | public class PropertiesUtil |
| 35 | { |
| 36 | /** |
| 37 | * Load properties from either a file in the templatePath if there |
| 38 | * is one or the classPath. |
| 39 | * |
| 40 | * @param propertiesFile the properties file to load through |
| 41 | * either the templatePath or the classpath. |
| 42 | * @return a properties instance filled with the properties found |
| 43 | * in the file or an empty instance if no file was found. |
| 44 | */ |
| 45 | public Properties load(String propertiesFile) |
| 46 | { |
| 47 | Properties properties = new Properties(); |
| 48 | String templatePath = Generator.getInstance().getTemplatePath(); |
| 49 | if (templatePath != null) |
| 50 | { |
| 51 | properties = loadFromTemplatePath(propertiesFile); |
| 52 | } |
| 53 | else |
| 54 | { |
| 55 | properties = loadFromClassPath(propertiesFile); |
| 56 | } |
| 57 | |
| 58 | return properties; |
| 59 | |
| 60 | } |
| 61 | |
| 62 | /** |
| 63 | * Load a properties file from the templatePath defined in the |
| 64 | * generator. As the templatePath can contains multiple paths, |
| 65 | * it will cycle through them to find the file. The first file |
| 66 | * that can be successfully loaded is considered. (kind of |
| 67 | * like the java classpath), it is done to clone the Velocity |
| 68 | * process of loading templates. |
| 69 | * |
| 70 | * @param propertiesFile the properties file to load. It must be |
| 71 | * a relative pathname. |
| 72 | * @return a properties instance loaded with the properties from |
| 73 | * the file. If no file can be found it returns an empty instance. |
| 74 | */ |
| 75 | protected Properties loadFromTemplatePath(String propertiesFile) |
| 76 | { |
| 77 | Properties properties = new Properties(); |
| 78 | String templatePath = Generator.getInstance().getTemplatePath(); |
| 79 | |
| 80 | // We might have something like the following: |
| 81 | // |
| 82 | // #set ($dbprops = $properties.load("$generator.templatePath/path/props") |
| 83 | // |
| 84 | // as we have in Torque but we want people to start using |
| 85 | // |
| 86 | // #set ($dbprops = $properties.load("path/props") |
| 87 | // |
| 88 | // so that everything works from the filesystem or from |
| 89 | // a JAR. So the actual Generator.getTemplatePath() |
| 90 | // is not deprecated but it's use in templates |
| 91 | // should be. |
| 92 | StringTokenizer st = new StringTokenizer(templatePath, ","); |
| 93 | while (st.hasMoreTokens()) |
| 94 | { |
| 95 | String templateDir = st.nextToken(); |
| 96 | try |
| 97 | { |
| 98 | // If the properties file is being pulled from the |
| 99 | // file system and someone is using the method whereby |
| 100 | // the properties file is assumed to be in the template |
| 101 | // path and they are simply using: |
| 102 | // |
| 103 | // #set ($dbprops = $properties.load("props") (1) |
| 104 | // |
| 105 | // than we have to tack on the templatePath in order |
| 106 | // for the properties file to be found. We want (1) |
| 107 | // to work whether the generation is being run from |
| 108 | // the file system or from a JAR file. |
| 109 | String fullPath = propertiesFile; |
| 110 | |
| 111 | // FIXME probably not that clever since there could be |
| 112 | // a mix of file separators and the test will fail :-( |
| 113 | if (!fullPath.startsWith(templateDir)) |
| 114 | { |
| 115 | fullPath = templateDir + "/" + propertiesFile; |
| 116 | } |
| 117 | |
| 118 | properties.load(new FileInputStream(fullPath)); |
| 119 | // first pick wins, we don't need to go further since |
| 120 | // we found a valid file. |
| 121 | break; |
| 122 | } |
| 123 | catch (Exception e) |
| 124 | { |
| 125 | // do nothing |
| 126 | } |
| 127 | } |
| 128 | return properties; |
| 129 | } |
| 130 | |
| 131 | /** |
| 132 | * Load a properties file from the classpath |
| 133 | * |
| 134 | * @param propertiesFile the properties file to load. |
| 135 | * @return a properties instance loaded with the properties from |
| 136 | * the file. If no file can be found it returns an empty instance. |
| 137 | */ |
| 138 | protected Properties loadFromClassPath(String propertiesFile) |
| 139 | { |
| 140 | Properties properties = new Properties(); |
| 141 | ClassLoader classLoader = this.getClass().getClassLoader(); |
| 142 | |
| 143 | try |
| 144 | { |
| 145 | // This is a hack for now to make sure that properties |
| 146 | // files referenced in the filesystem work in |
| 147 | // a JAR file. We have to deprecate the use |
| 148 | // of $generator.templatePath in templates first |
| 149 | // and this hack will allow those same templates |
| 150 | // that use $generator.templatePath to work in |
| 151 | // JAR files. |
| 152 | if (propertiesFile.startsWith("$generator")) |
| 153 | { |
| 154 | propertiesFile = propertiesFile.substring( |
| 155 | "$generator.templatePath/".length()); |
| 156 | } |
| 157 | |
| 158 | InputStream inputStream = classLoader.getResourceAsStream(propertiesFile); |
| 159 | properties.load(inputStream); |
| 160 | } |
| 161 | catch (IOException ioe) |
| 162 | { |
| 163 | // do nothing |
| 164 | } |
| 165 | return properties; |
| 166 | } |
| 167 | } |