AbstractBeanDefinitionReader：

    public int loadBeanDefinitions(String location, @Nullable Set<Resource> actualResources) throws BeanDefinitionStoreException {//获取资源加载器，该资源加载器事实上是ClassPathXmlApplicationContext对象，从哪里得知呢？ResourceLoader resourceLoader = getResourceLoader(); //代码1if (resourceLoader == null) {throw new BeanDefinitionStoreException("Cannot import bean definitions from location [" + location + "]: no ResourceLoader available");}//由于ClassPathXmlApplicationContext实现ResourcePatternResolver，将执行以下分支if (resourceLoader instanceof ResourcePatternResolver) {try {//将字符串类型的配置文件转换为Spring能识别的Resource对象资源Resource[] resources = ((ResourcePatternResolver) resourceLoader).getResources(location);//代码2//进入重载的loadBeanDefinitions(Resource..)方法//最终调用由XmlBeanDefinitionReader实现的loadBeanDefinitions(Resource resource)方法//主线int loadCount = loadBeanDefinitions(resources);if (actualResources != null) {for (Resource resource : resources) {actualResources.add(resource);}}...return loadCount;}catch (IOException ex) {...}}else {//仅可以从绝对路径加载单独的resourceResource resource = resourceLoader.getResource(location);int loadCount = loadBeanDefinitions(resource);if (actualResources != null) {actualResources.add(resource);}...return loadCount;}}

由上一步 getResourceLoader()的分析我们可以得知，（详细参考：
getResourceLoader()分析
）获取到的是ClassPathXmlApplicationContext对象，因此：

代码2的getResources(location)实际上调用的是ClassPathXmlApplicationContext对象的getResources方法，由ClassPathXmlApplicationContext的父类AbstractApplicationContext提供具体的实现。

点入其具体实现如下，AbstractApplicationContext：

    private ResourcePatternResolver resourcePatternResolver;public Resource[] getResources(String locationPattern) throws IOException {return this.resourcePatternResolver.getResources(locationPattern);}

此处的实际getResources实现其实是交由成员变量resourcePatternResolver来执行，我们看看resourcePatternResolver是如何初始化的：

    public AbstractApplicationContext() {this.resourcePatternResolver = getResourcePatternResolver();}protected ResourcePatternResolver getResourcePatternResolver() {return new PathMatchingResourcePatternResolver(this);}

有上述代码可看出，在最开始构造ClassPathXmlApplicationContext对象的时候，调用父类AbstractApplicationContext的无参构造器，初始化了resourcePatternResolver，并且具体的实现类是PathMatchingResourcePatternResolver。