spring加载properties属性文件到内存

package com.jdd.broker.admin.aspect;
import java.util.HashMap;
import java.util.Map;
import java.util.Properties;
import java.util.Map.Entry;
import org.springframework.beans.BeansException;
import org.springframework.beans.factory.config.ConfigurableListableBeanFactory;
import org.springframework.beans.factory.config.PropertyPlaceholderConfigurer;
import org.springframework.util.PropertyPlaceholderHelper;

public class CustomPropertyConfigurer extends PropertyPlaceholderConfigurer{
private static Map<String,String> properties = new HashMap<String,String>();
protected void processProperties(
ConfigurableListableBeanFactory beanFactoryToProcess,
Properties props) throws BeansException {
// cache the properties
PropertyPlaceholderHelper helper = new PropertyPlaceholderHelper(
DEFAULT_PLACEHOLDER_PREFIX, DEFAULT_PLACEHOLDER_SUFFIX, DEFAULT_VALUE_SEPARATOR, false);
for(Entry<Object,Object> entry:props.entrySet()){
String stringKey = String.valueOf(entry.getKey());
String stringValue = String.valueOf(entry.getValue());
stringValue = helper.replacePlaceholders(stringValue, props);
properties.put(stringKey, stringValue);
}
super.processProperties(beanFactoryToProcess, props);
}

public static Map<String, String> getProperties() {
return properties;
}

public static String getProperty(String key){
return properties.get(key);
}
}

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:p="http://www.springframework.org/schema/p"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-3.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-3.0.xsd" default-lazy-init="true" default-autowire="byName" default-init-method="" default-destroy-method="">

<bean id="propertyConfigurer"  class="com.jdd.broker.admin.aspect.CustomPropertyConfigurer">
<property name="locations">
<list>
<value>classpath:/jdbc.properties</value>
</list>
</property>
</bean>

</beans>

jdbc.driverClassName=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://rdsvl6l6emtdjrk6yi4k3public.mysql.rds.aliyuncs.com:3306/test_crowd?useUnicode=true&characterEncoding=utf8&allowMultiQueries=true
jdbc.username=test_crowd
jdbc.password=test_crowd

package com.jdd.broker.admin.aspect;
import java.util.Map;
import org.springframework.context.support.ClassPathXmlApplicationContext;
public class Main {
public static void main(String[] args) {
new ClassPathXmlApplicationContext("spring-mvc.xml");
Map<String, String> properties = CustomPropertyConfigurer.getProperties();
System.out.println(properties);
}
}