Spring源码学习--XmlWebApplicationContext（四）

刺骨的言语ヽ痛彻心扉 2022-07-13 18:20 118阅读 0赞

ApplicationContext应用上下文体系如下：

![Image 1][]

XmlWebApplicationContext是用于web容器的应用上下文的，其也没有太多操作，主要还是applicationContext.xml的解析操作，完整源码如下

public class XmlWebApplicationContext extends AbstractRefreshableWebApplicationContext {
    	/** Default config location for the root context */
    	//默认配置文件地址
    	public static final String DEFAULT_CONFIG_LOCATION = "/WEB-INF/applicationContext.xml";
    	/** Default prefix for building a config location for a namespace */
    	public static final String DEFAULT_CONFIG_LOCATION_PREFIX = "/WEB-INF/";
    	/** Default suffix for building a config location for a namespace */
    	public static final String DEFAULT_CONFIG_LOCATION_SUFFIX = ".xml";
    	//解析applicationContext.xml
    	@Override
    	protected void loadBeanDefinitions(DefaultListableBeanFactory beanFactory) throws BeansException, IOException {
    		// Create a new XmlBeanDefinitionReader for the given BeanFactory.
    		XmlBeanDefinitionReader beanDefinitionReader = new XmlBeanDefinitionReader(beanFactory);
    		// Configure the bean definition reader with this context's
    		// resource loading environment.
    		beanDefinitionReader.setEnvironment(getEnvironment());
    		beanDefinitionReader.setResourceLoader(this);
    		beanDefinitionReader.setEntityResolver(new ResourceEntityResolver(this));
    		// Allow a subclass to provide custom initialization of the reader,
    		// then proceed with actually loading the bean definitions.
    		initBeanDefinitionReader(beanDefinitionReader);
    		loadBeanDefinitions(beanDefinitionReader);
    	}
    	protected void initBeanDefinitionReader(XmlBeanDefinitionReader beanDefinitionReader) {
    	}
    	protected void loadBeanDefinitions(XmlBeanDefinitionReader reader) throws IOException {
    		String[] configLocations = getConfigLocations();
    		if (configLocations != null) {
    			for (String configLocation : configLocations) {
    				reader.loadBeanDefinitions(configLocation);
    			}
    		}
    	}
    	//获取默认配置文件地址
    	@Override
    	protected String[] getDefaultConfigLocations() {
    		if (getNamespace() != null) {
    			return new String[] {DEFAULT_CONFIG_LOCATION_PREFIX + getNamespace() + DEFAULT_CONFIG_LOCATION_SUFFIX};
    		}
    		else {
    			return new String[] {DEFAULT_CONFIG_LOCATION};
    		}
    	}
    }

[Image 1]: