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/** * Copyright 2003-2007 Luck Consulting Pty Ltd * * 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 net.sf.ehcache.config; import net.sf.ehcache.CacheException; import net.sf.ehcache.util.ClassLoaderUtil; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import javax.xml.parsers.SAXParser; import javax.xml.parsers.SAXParserFactory; import java.io.BufferedInputStream; import java.io.ByteArrayInputStream; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.net.URL; import java.util.HashSet; import java.util.Iterator; import java.util.Set; import java.util.regex.Matcher; import java.util.regex.Pattern; /** * A utility class which configures beans from XML, using reflection. * * @author Greg Luck * @version $Id: ConfigurationFactory.java 631 2008-05-23 22:17:52Z gregluck $ */ public final class ConfigurationFactory { private static final Log LOG = LogFactory.getLog(ConfigurationFactory.class.getName()); private static final String DEFAULT_CLASSPATH_CONFIGURATION_FILE = "/ehcache.xml"; private static final String FAILSAFE_CLASSPATH_CONFIGURATION_FILE = "/ehcache-failsafe.xml"; /** * Constructor. */ private ConfigurationFactory() { } /** * Configures a bean from an XML file. */ public static Configuration parseConfiguration(final File file) throws CacheException { if (file == null) { throw new CacheException("Attempt to configure ehcache from null file."); } if (LOG.isDebugEnabled()) { LOG.debug("Configuring ehcache from file: " + file.toString()); } Configuration configuration = null; InputStream input = null; try { input = new BufferedInputStream(new FileInputStream(file)); configuration = parseConfiguration(input); } catch (Exception e) { throw new CacheException("Error configuring from " + file + ". Initial cause was " + e.getMessage(), e); } finally { try { if (input != null) { input.close(); } } catch (IOException e) { LOG.error("IOException while closing configuration input stream. Error was " + e.getMessage()); } } return configuration; } /** * Configures a bean from an XML file available as an URL. */ public static Configuration parseConfiguration(final URL url) throws CacheException { if (LOG.isDebugEnabled()) { LOG.debug("Configuring ehcache from URL: " + url); } Configuration configuration; InputStream input = null; try { input = url.openStream(); configuration = parseConfiguration(input); } catch (Exception e) { throw new CacheException("Error configuring from " + url + ". Initial cause was " + e.getMessage(), e); } finally { try { if (input != null) { input.close(); } } catch (IOException e) { LOG.error("IOException while closing configuration input stream. Error was " + e.getMessage()); } } return configuration; } /** * Configures a bean from an XML file in the classpath. */ public static Configuration parseConfiguration() throws CacheException { ClassLoader standardClassloader = ClassLoaderUtil.getStandardClassLoader(); URL url = null; if (standardClassloader != null) { url = standardClassloader.getResource(DEFAULT_CLASSPATH_CONFIGURATION_FILE); } if (url == null) { url = ConfigurationFactory.class.getResource(DEFAULT_CLASSPATH_CONFIGURATION_FILE); } if (url != null) { if (LOG.isDebugEnabled()) { LOG.debug("Configuring ehcache from ehcache.xml found in the classpath: " + url); } } else { url = ConfigurationFactory.class.getResource(FAILSAFE_CLASSPATH_CONFIGURATION_FILE); if (LOG.isWarnEnabled()) { LOG.warn("No configuration found. Configuring ehcache from ehcache-failsafe.xml " + " found in the classpath: " + url); } } return parseConfiguration(url); } /** * Configures a bean from an XML input stream. */ public static Configuration parseConfiguration(final InputStream inputStream) throws CacheException { if (LOG.isDebugEnabled()) { LOG.debug("Configuring ehcache from InputStream"); } Configuration configuration = new Configuration(); try { InputStream translatedInputStream = translateSystemProperties(inputStream); final SAXParser parser = SAXParserFactory.newInstance().newSAXParser(); final BeanHandler handler = new BeanHandler(configuration); parser.parse(translatedInputStream, handler); } catch (Exception e) { throw new CacheException("Error configuring from input stream. Initial cause was " + e.getMessage(), e); } return configuration; } /** * Translates system properties which can be added as tokens to the config file using ${token} syntax. * <p/> * So, if the config file contains a character sequence "multicastGroupAddress=${multicastAddress}", and there is a system property * multicastAddress=230.0.0.12 then the translated sequence becomes "multicastGroupAddress=230.0.0.12" * * @param inputStream * @return a translated stream */ private static InputStream translateSystemProperties(InputStream inputStream) throws IOException { StringBuffer stringBuffer = new StringBuffer(); int c; while ((c = inputStream.read()) != -1) { stringBuffer.append((char) c); } String configuration = stringBuffer.toString(); Set tokens = extractPropertyTokens(configuration); Iterator tokenIterator = tokens.iterator(); while (tokenIterator.hasNext()) { String token = (String) tokenIterator.next(); String leftTrimmed = token.replaceAll("\\$\\{", ""); String trimmedToken = leftTrimmed.replaceAll("\\}", ""); String property = System.getProperty(trimmedToken); if (property == null) { if (LOG.isDebugEnabled()) { LOG.debug("Did not find a system property for the " + token + " token specified in the configuration.Replacing with \"\""); } } else { configuration = configuration.replaceAll("\\$\\{" + trimmedToken + "\\}", property); if (LOG.isDebugEnabled()) { LOG.debug("Found system property value of " + property + " for the " + token + " token specified in the configuration."); } } } return new ByteArrayInputStream(configuration.getBytes()); } /** * Extracts properties of the form ${...} * @param sourceDocument the source document * @return a Set of properties. So, duplicates are only counted once. */ static Set extractPropertyTokens(String sourceDocument) { Set propertyTokens = new HashSet(); Pattern pattern = Pattern.compile("\\$\\{.+?\\}"); Matcher matcher = pattern.matcher(sourceDocument); while (matcher.find()) { String token = matcher.group(); propertyTokens.add(token); } return propertyTokens; } }