com.reger.dubbo.config.PropertySourcesDeducer Maven / Gradle / Ivy
/*
* Copyright 2012-2018 the original author or authors.
*
* 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 com.reger.dubbo.config;
import java.util.Map;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.springframework.context.ApplicationContext;
import org.springframework.context.support.PropertySourcesPlaceholderConfigurer;
import org.springframework.core.env.ConfigurableEnvironment;
import org.springframework.core.env.Environment;
import org.springframework.core.env.MutablePropertySources;
import org.springframework.core.env.PropertySources;
import org.springframework.util.Assert;
/**
* Utility to deduce the {@link PropertySources} to use for configuration binding.
*
* @author Phillip Webb
*/
class PropertySourcesDeducer {
private static final Log logger = LogFactory.getLog(PropertySourcesDeducer.class);
private final ApplicationContext applicationContext;
PropertySourcesDeducer(ApplicationContext applicationContext) {
this.applicationContext = applicationContext;
}
public PropertySources getPropertySources() {
MutablePropertySources environmentPropertySources = extractEnvironmentPropertySources();
PropertySourcesPlaceholderConfigurer placeholderConfigurer = getSinglePropertySourcesPlaceholderConfigurer();
if (placeholderConfigurer == null) {
Assert.state(environmentPropertySources != null,
"Unable to obtain PropertySources from "
+ "PropertySourcesPlaceholderConfigurer or Environment");
return environmentPropertySources;
}
PropertySources appliedPropertySources = placeholderConfigurer
.getAppliedPropertySources();
if (environmentPropertySources == null) {
return appliedPropertySources;
}
return merge(environmentPropertySources, appliedPropertySources);
}
private MutablePropertySources extractEnvironmentPropertySources() {
Environment environment = this.applicationContext.getEnvironment();
if (environment instanceof ConfigurableEnvironment) {
return ((ConfigurableEnvironment) environment).getPropertySources();
}
return null;
}
private PropertySourcesPlaceholderConfigurer getSinglePropertySourcesPlaceholderConfigurer() {
// Take care not to cause early instantiation of all FactoryBeans
Map beans = this.applicationContext
.getBeansOfType(PropertySourcesPlaceholderConfigurer.class, false, false);
if (beans.size() == 1) {
return beans.values().iterator().next();
}
if (beans.size() > 1 && logger.isWarnEnabled()) {
logger.warn(
"Multiple PropertySourcesPlaceholderConfigurer " + "beans registered "
+ beans.keySet() + ", falling back to Environment");
}
return null;
}
private PropertySources merge(PropertySources environmentPropertySources,
PropertySources appliedPropertySources) {
FilteredPropertySources filtered = new FilteredPropertySources(
appliedPropertySources,
PropertySourcesPlaceholderConfigurer.ENVIRONMENT_PROPERTIES_PROPERTY_SOURCE_NAME);
return new CompositePropertySources(filtered, environmentPropertySources);
}
}