org.springframework.beans.factory.config.PropertiesFactoryBean Maven / Gradle / Ivy
/*
* Copyright 2002-2005 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 org.springframework.beans.factory.config;
import java.io.IOException;
import java.util.Properties;
import org.springframework.beans.factory.FactoryBean;
import org.springframework.beans.factory.InitializingBean;
import org.springframework.core.io.support.PropertiesLoaderSupport;
/**
* Allows for making a properties file from a classpath location available
* as Properties instance in a bean factory. Can be used to populate
* any bean property of type Properties via a bean reference.
*
* Supports loading from a properties file and/or setting local properties
* on this FactoryBean. The created Properties instance will be merged from
* loaded and local values. If neither a location nor local properties are set,
* an exception will be thrown on initialization.
*
*
Can create a singleton or a new object on each request.
* Default is singleton.
*
* @author Juergen Hoeller
* @see java.util.Properties
*/
public class PropertiesFactoryBean extends PropertiesLoaderSupport
implements FactoryBean, InitializingBean {
private boolean singleton = true;
private Object singletonInstance;
/**
* Set if a singleton should be created, or a new object
* on each request else. Default is "true" (a singleton).
*/
public final void setSingleton(boolean singleton) {
this.singleton = singleton;
}
public final boolean isSingleton() {
return singleton;
}
public final void afterPropertiesSet() throws IOException {
if (this.singleton) {
this.singletonInstance = createInstance();
}
}
public final Object getObject() throws IOException {
if (this.singleton) {
return this.singletonInstance;
}
else {
return createInstance();
}
}
public Class getObjectType() {
return Properties.class;
}
/**
* Template method that subclasses may override to construct the object
* returned by this factory. Default returns the plain merged Properties.
*
Invoked on initialization of this FactoryBean in case of
* a singleton; else, on each getObject() call.
* @return the object returned by this factory
* @throws IOException if an exception occured during properties loading
* @see #getObject()
* @see #mergeProperties()
*/
protected Object createInstance() throws IOException {
return mergeProperties();
}
}