Spring注入的成员属性HttpServletRequest是线程安全的吗？【享学Spring MVC】

@GetMapping("/test/request")
public Object testRequest(HttpServletRequest request) {
    System.out.println(request.getClass());
    return "success";
}

class org.apache.catalina.connector.RequestFacade

@GetMapping("/test/request")
public Object testRequest(HttpServletRequest request) {
	// 从请求上下文里获取Request对象
    ServletRequestAttributes requestAttributes = ServletRequestAttributes.class.cast(RequestContextHolder.getRequestAttributes());
    HttpServletRequest contextRequest = requestAttributes.getRequest();
    System.out.println(contextRequest.getClass());

    // 比较两个是否是同一个实例
    System.out.println(contextRequest == request);
    return "success";
}

class org.apache.catalina.connector.RequestFacade
true

public abstract class BaseController {

	public HttpServletRequest getRequest() {
		return ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest();
	}
	public HttpServletResponse getResponse() {
		return ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getResponse();
	}
    public HttpSession getSession() {
		return ((ServletRequestAttributes) RequestContextHolder.getRequestAttributes()).getRequest().getSession();
	}

}

@Autowired
HttpServletRequest requestAuto;

@GetMapping("/test/request")
public Object testRequest(HttpServletRequest request) {
    System.out.println(requestAuto.getClass());
    System.out.println(requestAuto == request);
    return "success";
}

class com.sun.proxy.$Proxy70
false

private HttpServletRequest request; 
@ModelAttribute
public void bindRequest(HttpServletRequest request) {
    this.request = request; 
}

AutowireUtils：
	
	private static class ObjectFactoryDelegatingInvocationHandler implements InvocationHandler, Serializable {

		private final ObjectFactory<?> objectFactory;
		public ObjectFactoryDelegatingInvocationHandler(ObjectFactory<?> objectFactory) {
			this.objectFactory = objectFactory;
		}

		@Override
		public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
			String methodName = method.getName();
			if (methodName.equals("equals")) {
				return (proxy == args[0]);
			} else if (methodName.equals("hashCode")) {
				return System.identityHashCode(proxy);
			} else if (methodName.equals("toString")) {
				return this.objectFactory.toString();
			}
		
			// 执行目标方法。注意：目标实例对象是objectFactory.getObject()
			try {
				return method.invoke(this.objectFactory.getObject(), args);
			} catch (InvocationTargetException ex) {
				throw ex.getTargetException();
			}
		}
	}

WebApplicationContextUtils：

	public static void registerWebApplicationScopes(ConfigurableListableBeanFactory beanFactory, @Nullable ServletContext sc) {
		
		// web容器下新增支持了三种scope
		// 非web容器（默认）只有单例和多例两种嘛
		beanFactory.registerScope(WebApplicationContext.SCOPE_REQUEST, new RequestScope());
		beanFactory.registerScope(WebApplicationContext.SCOPE_SESSION, new SessionScope());
		if (sc != null) {
			ServletContextScope appScope = new ServletContextScope(sc);
			beanFactory.registerScope(WebApplicationContext.SCOPE_APPLICATION, appScope);
			sc.setAttribute(ServletContextScope.class.getName(), appScope);


			// ==================依赖注入=================
			// 这里决定了，若你依赖注入ServletRequest的话，就使用RequestObjectFactory来处理你
			beanFactory.registerResolvableDependency(ServletRequest.class, new RequestObjectFactory());
			beanFactory.registerResolvableDependency(ServletResponse.class, new ResponseObjectFactory());
			beanFactory.registerResolvableDependency(HttpSession.class, new SessionObjectFactory());
			beanFactory.registerResolvableDependency(WebRequest.class, new WebRequestObjectFactory());
		}

	}

WebApplicationContextUtils：

	private static class RequestObjectFactory implements ObjectFactory<ServletRequest>, Serializable {
		// 从当前请求上下文里找到Request对象
		@Override
		public ServletRequest getObject() {
			return currentRequestAttributes().getRequest();
		}
		...
	}

	// 从当前请求上下文：RequestContextHolder里找到请求属性，进而就可以拿到请求对象、响应对象等等了
	private static ServletRequestAttributes currentRequestAttributes() {
		RequestAttributes requestAttr = RequestContextHolder.currentRequestAttributes();
		if (!(requestAttr instanceof ServletRequestAttributes)) {
			throw new IllegalStateException("Current request is not a servlet request");
		}
		return (ServletRequestAttributes) requestAttr;
	}

// 它是个工具类：用抽象类表示而已  所有方法均静态
public abstract class RequestContextHolder {

	private static final ThreadLocal<RequestAttributes> requestAttributesHolder = new NamedThreadLocal<>("Request attributes");
	private static final ThreadLocal<RequestAttributes> inheritableRequestAttributesHolder = new NamedInheritableThreadLocal<>("Request context");
	... // 省略set、get、reset等方法	
}

FrameworkServlet：

	// 处理请求的方法
	protected final void processRequest(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		...
		ServletRequestAttributes requestAttributes = buildRequestAttributes(request, response, previousAttributes);
		...
		initContextHolders(request, localeContext, requestAttributes);
		try {
			// 抽象方法：交给DispatcherServlet去实现
			doService(request, response);
		} catch { 
			...
		} finally {
			resetContextHolders(request, previousLocaleContext, previousAttributes);
			...
		}
	}

	private void initContextHolders(...) {
		...
		RequestContextHolder.setRequestAttributes(requestAttributes, this.threadContextInheritable);
	}

@Autowired
HttpServletRequest requestAuto;

@GetMapping("/test/request")
public Object testRequest() {
    new Thread(() -> {
        String name = requestAuto.getParameter("name");
        System.out.println(name);
    }).start();
    return "success";
}

private static final ExecutorService THREAD_POOL = Executors.newFixedThreadPool(10);

@Autowired
HttpServletRequest requestAuto;
@GetMapping("/test/request")
public Object testRequest() {
    THREAD_POOL.execute(() -> {
        String name = requestAuto.getParameter("name");
        System.out.println(name);
    });
    return "success";
}