001 /**
002 * Copyright 2005-2013 The Kuali Foundation
003 *
004 * Licensed under the Educational Community License, Version 2.0 (the "License");
005 * you may not use this file except in compliance with the License.
006 * You may obtain a copy of the License at
007 *
008 * http://www.opensource.org/licenses/ecl2.php
009 *
010 * Unless required by applicable law or agreed to in writing, software
011 * distributed under the License is distributed on an "AS IS" BASIS,
012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
013 * See the License for the specific language governing permissions and
014 * limitations under the License.
015 */
016 package edu.samplu.common;
017
018 import freemarker.template.Configuration;
019 import freemarker.template.Template;
020 import freemarker.template.TemplateException;
021 import org.apache.commons.io.FileUtils;
022 import org.springframework.ui.freemarker.FreeMarkerTemplateUtils;
023
024 import java.io.File;
025 import java.io.IOException;
026 import java.io.InputStream;
027 import java.util.Enumeration;
028 import java.util.Properties;
029
030 /**
031 * FreemarkerUtil loads properties from user defined InputStream. systemPropertiesOverride should be used to override properties
032 * using a given key to identify them from JVM args. (i.e. -Dkey.name to override the name property in the key file.)
033 * TODO setup so the loading and overriding of properties is done for the user rather then them having to call it.
034 * @author Kuali Rice Team (rice.collab@kuali.org)
035 */
036 public class FreemarkerUtil {
037
038 protected Configuration cfg;
039
040 /**
041 * Calls ftlWrite that also accepts a key, using the output getName as the key.
042 * @param output
043 * @param template
044 * @return
045 * @throws java.io.IOException
046 * @throws freemarker.template.TemplateException
047 */
048 public File ftlWrite(File output, Template template, InputStream inputStream) throws IOException, TemplateException {
049
050 return ftlWrite(output.getName(), output, template, inputStream);
051 }
052
053 /**
054 * Loads properties from user defined properties file, if not available uses resource file
055 *
056 * writes processed template to file
057 * @param key
058 * @param output
059 * @param template
060 * @throws IOException
061 * @throws TemplateException
062 */
063 public static File ftlWrite(String key, File output, Template template, InputStream inputStream) throws IOException, TemplateException {
064 Properties props = loadProperties(inputStream);
065 systemPropertiesOverride(props, key);
066 File outputFile = writeTemplateToFile(output, template, props);
067
068 return outputFile;
069 }
070
071 protected static Properties loadProperties(InputStream inputStream) throws IOException {
072 Properties props = new Properties();
073
074 if(inputStream != null) {
075 props.load(inputStream);
076 }
077
078 return props;
079 }
080
081 /**
082 *
083 * @param file
084 * @param template
085 * @param props
086 * @return
087 * @throws IOException
088 * @throws freemarker.template.TemplateException
089 */
090 protected static File writeTemplateToFile(File file, Template template, Properties props) throws IOException, TemplateException {
091 String output = FreeMarkerTemplateUtils.processTemplateIntoString(template, props);
092 FileUtils.writeStringToFile(file, output);
093
094 return file;
095 }
096
097 /**
098 * -Dkey.propertyname= to override the property value for propertyname.
099 * @param props
100 */
101 public static void systemPropertiesOverride(Properties props, String key) {
102 Enumeration<?> names = props.propertyNames();
103 Object nameObject;
104 String name;
105 while (names.hasMoreElements()) {
106 nameObject = names.nextElement();
107 if (nameObject instanceof String) {
108 name = (String)nameObject;
109 props.setProperty(name, System.getProperty(key + "." + name, props.getProperty(name)));
110 }
111 }
112 }
113
114 }