spring源码（7）alias标签的解析

<bean id="some" class="src.com.Some"/>
<alias name="some" alias="someJava,oneBean,twoBean"/>

protected void processAliasRegistration(Element ele) {
//--获取“name”、“alias”属性
/*
*  <bean id="some" class="src.com.Some"/>
*  <alias name="some" alias="someJava,oneBean,twoBean"/>
*/
//获取name属性
String name = ele.getAttribute(NAME_ATTRIBUTE);
//获取alias属性
String alias = ele.getAttribute(ALIAS_ATTRIBUTE);
boolean valid = true;
if (!StringUtils.hasText(name)) {
getReaderContext().error("Name must not be empty", ele);
valid = false;
}
if (!StringUtils.hasText(alias)) {
getReaderContext().error("Alias must not be empty", ele);
valid = false;
}
if (valid) {
try {
//注册别名
getReaderContext().getRegistry().registerAlias(name, alias);
}
catch (Exception ex) {
getReaderContext().error("Failed to register alias '" + alias +
"' for bean with name '" + name + "'", ele, ex);
}
//通知监听者
getReaderContext().fireAliasRegistered(name, alias, extractSource(ele));
}
}