StoreLoader.java
/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You 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 org.apache.catalina.storeconfig;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.net.URL;
import org.apache.juli.logging.Log;
import org.apache.juli.logging.LogFactory;
import org.apache.tomcat.util.digester.Digester;
import org.xml.sax.SAXException;
/**
* <b>XML Format </b>
*
* <pre>
* {@code
* <Registry name="" encoding="UTF-8" >
* <Description
* tag="Server"
* standard="true"
* default="true"
* tagClass="org.apache.catalina.core.StandardServer"
* storeFactoryClass="org.apache.catalina.storeconfig.StandardServerSF">
* <TransientAttributes>
* <Attribute></Attribute>
* </TransientAttributes>
* <TransientChildren>
* <Child></Child>
* </TransientChildren>
* </Description>
* ...
* </Registry>
* }
* </pre>
*
*
* Convention:
* <ul>
* <li>Factories at subpackage <i>org.apache.catalina.core.storeconfig.xxxSF
* </i>.</li>
* <li>Element name are the unique Class name</li>
* <li>SF for StoreFactory</li>
* <li>standard implementation is false</li>
* </ul>
* other things:
* <ul>
* <li>Registry XML format is a very good option</li>
* <li>Store format is not fix</li>
* <li>We hope with the parent declaration we can build recursive child store
* operation //dream</li>
* <li>Problem is to access child data from array,collections or normal detail
* object</li>
* <li>Default definitions for Listener, Valve Resource? - Based on interface
* type!</li>
* </ul>
*/
public class StoreLoader {
private static Log log = LogFactory.getLog(StoreLoader.class);
/**
* The <code>Digester</code> instance used to parse registry descriptors.
*/
protected static final Digester digester = createDigester();
private StoreRegistry registry;
private URL registryResource ;
/**
* @return Returns the registry.
*/
public StoreRegistry getRegistry() {
return registry;
}
/**
* @param registry
* The registry to set.
*/
public void setRegistry(StoreRegistry registry) {
this.registry = registry;
}
/**
* Create and configure the Digester we will be using for setup store
* registry.
* @return the XML digester that will be used to parse the configuration
*/
protected static Digester createDigester() {
long t1 = System.currentTimeMillis();
// Initialize the digester
Digester digester = new Digester();
digester.setValidating(false);
digester.setClassLoader(StoreRegistry.class.getClassLoader());
// Configure the actions we will be using
digester.addObjectCreate("Registry",
"org.apache.catalina.storeconfig.StoreRegistry", "className");
digester.addSetProperties("Registry");
digester
.addObjectCreate("Registry/Description",
"org.apache.catalina.storeconfig.StoreDescription",
"className");
digester.addSetProperties("Registry/Description");
digester.addRule("Registry/Description", new StoreFactoryRule(
"org.apache.catalina.storeconfig.StoreFactoryBase",
"storeFactoryClass",
"org.apache.catalina.storeconfig.StoreAppender",
"storeAppenderClass"));
digester.addSetNext("Registry/Description", "registerDescription",
"org.apache.catalina.storeconfig.StoreDescription");
digester.addCallMethod("Registry/Description/TransientAttribute",
"addTransientAttribute", 0);
digester.addCallMethod("Registry/Description/TransientChild",
"addTransientChild", 0);
long t2 = System.currentTimeMillis();
if (log.isDebugEnabled()) {
log.debug("Digester for server-registry.xml created " + (t2 - t1));
}
return digester;
}
/**
* Find main configuration file.
* @param aFile File name, absolute or relative
* to <code>${catalina.base}/conf</code>, if not specified
* <code>server-registry.xml</code> is used
* @return The file
*/
protected File serverFile(String aFile) {
if (aFile == null || aFile.length() < 1) {
aFile = "server-registry.xml";
}
File file = new File(aFile);
if (!file.isAbsolute()) {
file = new File(System.getProperty("catalina.base") + "/conf",
aFile);
}
try {
file = file.getCanonicalFile();
} catch (IOException e) {
log.error(e);
}
return file;
}
/**
* Load main configuration file from external source.
*
* @param aURL URL to the configuration file
*/
public void load(String aURL) {
synchronized (digester) {
File aRegistryFile = serverFile(aURL);
try {
registry = (StoreRegistry) digester.parse(aRegistryFile);
registryResource = aRegistryFile.toURI().toURL();
} catch (IOException e) {
log.error(e);
} catch (SAXException e) {
log.error(e);
}
}
}
/**
* Load from defaults
* <ul>
* <li>System Property URL catalina.storeregistry</li>
* <li>File ${catalina.base}/conf/server-registry.xml</li>
* <li>class resource org/apache/catalina/storeconfig/server-registry.xml
* </li>
* </ul>
*/
public void load() {
InputStream is = null;
registryResource = null ;
try {
String configUrl = getConfigUrl();
if (configUrl != null) {
is = (new URL(configUrl)).openStream();
if (log.isInfoEnabled()) {
log.info("Find registry server-registry.xml from system property at url "
+ configUrl);
}
registryResource = new URL(configUrl);
}
} catch (Throwable t) {
// Ignore
}
if (is == null) {
try {
File home = new File(getCatalinaBase());
File conf = new File(home, "conf");
File reg = new File(conf, "server-registry.xml");
is = new FileInputStream(reg);
if (log.isInfoEnabled()) {
log.info("Find registry server-registry.xml at file "
+ reg.getCanonicalPath());
}
registryResource = reg.toURI().toURL();
} catch (Throwable t) {
// Ignore
}
}
if (is == null) {
try {
is = StoreLoader.class
.getResourceAsStream("/org/apache/catalina/storeconfig/server-registry.xml");
if (log.isDebugEnabled()) {
log.debug("Find registry server-registry.xml at classpath resource");
}
registryResource = StoreLoader.class
.getResource("/org/apache/catalina/storeconfig/server-registry.xml");
} catch (Throwable t) {
// Ignore
}
}
if (is != null) {
try {
synchronized (digester) {
registry = (StoreRegistry) digester.parse(is);
}
} catch (Throwable t) {
log.error(t);
} finally {
try {
is.close();
} catch (IOException e) {
}
}
}
if (is == null) {
log.error("Failed to load server-registry.xml");
}
}
/**
* @return the catalina.home environment variable.
*/
private static String getCatalinaHome() {
return System.getProperty("catalina.home", System
.getProperty("user.dir"));
}
/**
* @return the catalina.base environment variable.
*/
private static String getCatalinaBase() {
return System.getProperty("catalina.base", getCatalinaHome());
}
/**
* @return the configuration URL.
*/
private static String getConfigUrl() {
return System.getProperty("catalina.storeconfig");
}
/**
* @return the registryResource.
*/
public URL getRegistryResource() {
return registryResource;
}
}