/**
* Copyright 2003-2008 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 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.logging.Logger;
import java.util.logging.Level;
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 744 2008-08-16 20:10:49Z gregluck $
*/
public final class ConfigurationFactory {
private static final Logger LOG = Logger.getLogger(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.isLoggable(Level.FINE)) {
LOG.fine("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.severe("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.isLoggable(Level.FINE)) {
LOG.fine("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.severe("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.isLoggable(Level.FINE)) {
LOG.fine("Configuring ehcache from ehcache.xml found in the classpath: " + url);
}
} else {
url = ConfigurationFactory.class.getResource(FAILSAFE_CLASSPATH_CONFIGURATION_FILE);
if (LOG.isLoggable(Level.WARNING)) {
LOG.warning("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.isLoggable(Level.FINE)) {
LOG.fine("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.isLoggable(Level.FINE)) {
LOG.fine("Did not find a system property for the " + token +
" token specified in the configuration.Replacing with \"\"");
}
} else {
configuration = configuration.replaceAll("\\$\\{" + trimmedToken + "\\}", property);
if (LOG.isLoggable(Level.FINE)) {
LOG.fine("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;
}
}