com.opensymphony.xwork2.config.ConfigurationManager Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of xwork Show documentation
Show all versions of xwork Show documentation
XWork is an command-pattern framework that is used to power WebWork
as well as other applications. XWork provides an Inversion of Control
container, a powerful expression language, data type conversion,
validation, and pluggable configuration.
/*
* Copyright (c) 2002-2006 by OpenSymphony
* All rights reserved.
*/
package com.opensymphony.xwork2.config;
import com.opensymphony.xwork2.util.FileManager;
import com.opensymphony.xwork2.config.impl.DefaultConfiguration;
import com.opensymphony.xwork2.config.providers.XmlConfigurationProvider;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
import java.util.concurrent.locks.Lock;
import java.util.concurrent.locks.ReentrantLock;
/**
* ConfigurationManager - central for XWork Configuration management, including
* its ConfigurationProvider.
*
* @author Jason Carreira
* @author tm_jee
* @version $Date: 2006-11-18 07:59:15 +0100 (Sat, 18 Nov 2006) $ $Id: ConfigurationManager.java 1218 2006-11-18 06:59:15Z tm_jee $
*/
public class ConfigurationManager {
protected static final Log LOG = LogFactory.getLog(ConfigurationManager.class);
protected Configuration configuration;
protected Lock providerLock = new ReentrantLock();
private List configurationProviders = new CopyOnWriteArrayList();
protected String defaultFrameworkBeanName;
public ConfigurationManager() {
this("xwork");
}
public ConfigurationManager(String name) {
this.defaultFrameworkBeanName = name;
}
/**
* Get the current XWork configuration object. By default an instance of DefaultConfiguration will be returned
*
* @see com.opensymphony.xwork2.config.impl.DefaultConfiguration
*/
public synchronized Configuration getConfiguration() {
if (configuration == null) {
setConfiguration(new DefaultConfiguration(defaultFrameworkBeanName));
try {
configuration.reload(getConfigurationProviders());
} catch (ConfigurationException e) {
setConfiguration(null);
throw e;
}
} else {
conditionalReload();
}
return configuration;
}
public synchronized void setConfiguration(Configuration configuration) {
this.configuration = configuration;
}
/**
* Get the current list of ConfigurationProviders. If no custom ConfigurationProviders have been added, this method
* will return a list containing only the default ConfigurationProvider, XMLConfigurationProvider. if a custom
* ConfigurationProvider has been added, then the XmlConfigurationProvider must be added by hand.
*
*
* TODO: the lazy instantiation of XmlConfigurationProvider should be refactored to be elsewhere. the behavior described above seems unintuitive.
*
* @return the list of registered ConfigurationProvider objects
* @see ConfigurationProvider
*/
public List getConfigurationProviders() {
providerLock.lock();
try {
if (configurationProviders.size() == 0) {
configurationProviders.add(new XmlConfigurationProvider("xwork.xml", true));
}
return configurationProviders;
} finally {
providerLock.unlock();
}
}
/**
* Set the list of configuration providers
*
* @param configurationProviders
*/
public void setConfigurationProviders(List configurationProviders) {
providerLock.lock();
try {
this.configurationProviders = new CopyOnWriteArrayList(configurationProviders);
} finally {
providerLock.unlock();
}
}
/**
* adds a configuration provider to the List of ConfigurationProviders. a given ConfigurationProvider may be added
* more than once
*
* @param provider the ConfigurationProvider to register
*/
public void addConfigurationProvider(ConfigurationProvider provider) {
if (!configurationProviders.contains(provider)) {
configurationProviders.add(provider);
}
}
/**
* clears the registered ConfigurationProviders. this method will call destroy() on each of the registered
* ConfigurationProviders
*
* @see com.opensymphony.xwork2.config.ConfigurationProvider#destroy
*/
public void clearConfigurationProviders() {
for (ConfigurationProvider configurationProvider : configurationProviders) {
try {
configurationProvider.destroy();
}
catch(Exception e) {
LOG.warn("error while destroying configuration provider ["+configurationProvider+"]", e);
}
}
configurationProviders.clear();
}
/**
* Destroy its managing Configuration instance
*/
public synchronized void destroyConfiguration() {
clearConfigurationProviders(); // let's destroy the ConfigurationProvider first
setConfigurationProviders(new CopyOnWriteArrayList());
if (configuration != null)
configuration.destroy(); // let's destroy it first, before nulling it.
configuration = null;
}
/**
* Reloads the Configuration files if the configuration files indicate that they need to be reloaded.
*/
public synchronized void conditionalReload() {
if (FileManager.isReloadingConfigs()) {
boolean reload;
if (LOG.isDebugEnabled()) {
LOG.debug("Checking ConfigurationProviders for reload.");
}
reload = false;
List providers = getConfigurationProviders();
for (ConfigurationProvider provider : providers) {
if (provider.needsReload()) {
if (LOG.isInfoEnabled()) {
LOG.info("Detected configuration provider "+provider+" needs to be reloaded. Reloading all providers.");
}
reload = true;
break;
}
}
if (reload) {
for (ConfigurationProvider configurationProvider : configurationProviders) {
try {
configurationProvider.destroy();
}
catch(Exception e) {
LOG.warn("error while destroying configuration provider ["+configurationProvider+"]", e);
}
}
configuration.reload(providers);
}
}
}
public synchronized void reload() {
getConfiguration().reload(getConfigurationProviders());
}
}