DispatcherServlet
1。初始化默認配置
?private static final String DEFAULT_STRATEGIES_PATH = "DispatcherServlet.properties";

static {
??// Load default strategy implementations from properties file.
??// This is currently strictly internal and not meant to be customized
??// by application developers.
??try {
???ClassPathResource resource = new ClassPathResource(DEFAULT_STRATEGIES_PATH, DispatcherServlet.class);
???InputStream is = resource.getInputStream();
???try {
????defaultStrategies.load(is);
???}
???finally {
????is.close();
???}
??}
??catch (IOException ex) {
???throw new IllegalStateException("Could not load 'DispatcherServlet.properties': " + ex.getMessage());
??}
?}

DispatcherServlet.properties 里面內容為：
org.springframework.web.servlet.LocaleResolver=org.springframework.web.servlet.i18n.AcceptHeaderLocaleResolver

org.springframework.web.servlet.ThemeResolver=org.springframework.web.servlet.theme.FixedThemeResolver

org.springframework.web.servlet.HandlerMapping=org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping

org.springframework.web.servlet.HandlerAdapter=org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter,\
?org.springframework.web.servlet.mvc.throwaway.ThrowawayControllerHandlerAdapter

org.springframework.web.servlet.ViewResolver=org.springframework.web.servlet.view.InternalResourceViewResolver

可以看出如果沒有相應的配置，DispatcherServlet就會調用默認設置