org.eclipse.jetty.spring.SpringConfigurationProcessor Maven / Gradle / Ivy
//
// ========================================================================
// Copyright (c) 1995-2016 Mort Bay Consulting Pty. Ltd.
// ------------------------------------------------------------------------
// All rights reserved. This program and the accompanying materials
// are made available under the terms of the Eclipse Public License v1.0
// and Apache License v2.0 which accompanies this distribution.
//
// The Eclipse Public License is available at
// http://www.eclipse.org/legal/epl-v10.html
//
// The Apache License v2.0 is available at
// http://www.opensource.org/licenses/apache2.0.php
//
// You may elect to redistribute this code under either of these licenses.
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//
package org.eclipse.jetty.spring;
import java.net.URL;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.Map;
import java.util.ServiceLoader;
import org.eclipse.jetty.util.log.Log;
import org.eclipse.jetty.util.log.Logger;
import org.eclipse.jetty.xml.ConfigurationProcessor;
import org.eclipse.jetty.xml.ConfigurationProcessorFactory;
import org.eclipse.jetty.xml.XmlConfiguration;
import org.eclipse.jetty.xml.XmlParser;
import org.springframework.beans.BeanWrapper;
import org.springframework.beans.PropertyValues;
import org.springframework.beans.factory.config.BeanDefinition;
import org.springframework.beans.factory.support.DefaultListableBeanFactory;
import org.springframework.beans.factory.xml.XmlBeanDefinitionReader;
import org.springframework.core.io.ByteArrayResource;
import org.springframework.core.io.Resource;
import org.springframework.core.io.UrlResource;
/**
* Spring ConfigurationProcessor
*
* A {@link ConfigurationProcessor} that uses a spring XML file to emulate the {@link XmlConfiguration} format.
*
* {@link XmlConfiguration} expects a primary object that is either passed in to a call to {@link #configure(Object)}
* or that is constructed by a call to {@link #configure()}. This processor looks for a bean definition
* with an id, name or alias of "Main" as uses that as the primary bean.
*
* The objects mapped by {@link XmlConfiguration#getIdMap()} are set as singletons before any configuration calls
* and if the spring configuration file contains a definition for the singleton id, the the singleton is updated
* with a call to {@link DefaultListableBeanFactory#configureBean(Object, String)}.
*
* The property map obtained via {@link XmlConfiguration#getProperties()} is set as a singleton called "properties"
* and values can be accessed by somewhat verbose
* usage of {@link org.springframework.beans.factory.config.MethodInvokingFactoryBean}.
*
* This processor is returned by the {@link SpringConfigurationProcessorFactory} for any XML document whos first
* element is "beans". The factory is discovered by a {@link ServiceLoader} for {@link ConfigurationProcessorFactory}.
*/
public class SpringConfigurationProcessor implements ConfigurationProcessor
{
private static final Logger LOG = Log.getLogger(SpringConfigurationProcessor.class);
private XmlConfiguration _configuration;
private DefaultListableBeanFactory _beanFactory;
private String _main;
@Override
public void init(URL url, XmlParser.Node config, XmlConfiguration configuration)
{
try
{
_configuration = configuration;
Resource resource = url != null
? new UrlResource(url)
: new ByteArrayResource(("" +
"" +
"" +
config).getBytes(StandardCharsets.UTF_8));
_beanFactory = new DefaultListableBeanFactory()
{
@Override
protected void applyPropertyValues(String beanName, BeanDefinition mbd, BeanWrapper bw, PropertyValues pvs)
{
_configuration.initializeDefaults(bw.getWrappedInstance());
super.applyPropertyValues(beanName, mbd, bw, pvs);
}
};
new XmlBeanDefinitionReader(_beanFactory).loadBeanDefinitions(resource);
}
catch (Exception e)
{
throw new RuntimeException(e);
}
}
@Override
public Object configure(Object obj) throws Exception
{
doConfigure();
return _beanFactory.configureBean(obj, _main);
}
/**
* Return a configured bean. If a bean has the id or alias of "Main", then it is returned, otherwise the first bean in the file is returned.
*
* @see org.eclipse.jetty.xml.ConfigurationProcessor#configure()
*/
@Override
public Object configure() throws Exception
{
doConfigure();
return _beanFactory.getBean(_main);
}
private void doConfigure()
{
_beanFactory.registerSingleton("properties", _configuration.getProperties());
// Look for the main bean;
for (String bean : _beanFactory.getBeanDefinitionNames())
{
LOG.debug("{} - {}", bean, Arrays.asList(_beanFactory.getAliases(bean)));
String[] aliases = _beanFactory.getAliases(bean);
if ("Main".equals(bean) || aliases != null && Arrays.asList(aliases).contains("Main"))
{
_main = bean;
break;
}
}
if (_main == null)
_main = _beanFactory.getBeanDefinitionNames()[0];
// Register id beans as singletons
Map idMap = _configuration.getIdMap();
LOG.debug("idMap {}", idMap);
for (String id : idMap.keySet())
{
LOG.debug("register {}", id);
_beanFactory.registerSingleton(id, idMap.get(id));
}
// Apply configuration to existing singletons
for (String id : idMap.keySet())
{
if (_beanFactory.containsBeanDefinition(id))
{
LOG.debug("reconfigure {}", id);
_beanFactory.configureBean(idMap.get(id), id);
}
}
// Extract id's for next time.
for (String id : _beanFactory.getSingletonNames())
idMap.put(id, _beanFactory.getBean(id));
}
}