SimpleControllerHandlerAdapter
public class SimpleControllerHandlerAdapter implements HandlerAdapter {
@Override
public boolean supports(Object handler) {
return (handler instanceof Controller);
}
@Override
public ModelAndView handle(HttpServletRequest request, HttpServletResponse response, Object handler)
throws Exception {
return ((Controller) handler).handleRequest(request, response);
}
@Override
public long getLastModified(HttpServletRequest request, Object handler) {
if (handler instanceof LastModified) {
return ((LastModified) handler).getLastModified(request);
}
return -1L;
}
}
public interface Controller {
/**
* Process the request and return a ModelAndView object which the DispatcherServlet
* will render. A {@code null} return value is not an error: It indicates that
* this object completed request processing itself, thus there is no ModelAndView
* to render.
* @param request current HTTP request
* @param response current HTTP response
* @return a ModelAndView to render, or {@code null} if handled directly
* @throws Exception in case of errors
*/
ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception;
}
HttpRequestHandlerAdapter
public class HttpRequestHandlerAdapter implements HandlerAdapter {
@Override
public boolean supports(Object handler) {
return (handler instanceof HttpRequestHandler);
}
@Override
public ModelAndView handle(HttpServletRequest request, HttpServletResponse response, Object handler)
throws Exception {
((HttpRequestHandler) handler).handleRequest(request, response);
return null;
}
@Override
public long getLastModified(HttpServletRequest request, Object handler) {
if (handler instanceof LastModified) {
return ((LastModified) handler).getLastModified(request);
}
return -1L;
}
}
public interface HttpRequestHandler {
/**
* Process the given request, generating a response.
* @param request current HTTP request
* @param response current HTTP response
* @throws ServletException in case of general errors
* @throws IOException in case of I/O errors
*/
void handleRequest(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException;
}
RequestMappingHandlerAdapter
public class RequestMappingHandlerAdapter extends AbstractHandlerMethodAdapter implements BeanFactoryAware,
InitializingBean {
@Override
public final boolean supports(Object handler) {
return handler instanceof HandlerMethod && supportsInternal((HandlerMethod) handler);
}
@Override
protected final ModelAndView handleInternal(HttpServletRequest request,
HttpServletResponse response, HandlerMethod handlerMethod) throws Exception {
if (getSessionAttributesHandler(handlerMethod).hasSessionAttributes()) {
// Always prevent caching in case of session attribute management.
checkAndPrepare(request, response, this.cacheSecondsForSessionAttributeHandlers, true);
}
else {
// Uses configured default cacheSeconds setting.
checkAndPrepare(request, response, true);
}
// Execute invokeHandlerMethod in synchronized block if required.
if (this.synchronizeOnSession) {
HttpSession session = request.getSession(false);
if (session != null) {
Object mutex = WebUtils.getSessionMutex(session);
synchronized (mutex) {
return invokeHandleMethod(request, response, handlerMethod);
}
}
}
return invokeHandleMethod(request, response, handlerMethod);
}
/**
* This implementation always returns -1. An {@code @RequestMapping}
* method can calculate the lastModified value, call
* {@link WebRequest#checkNotModified(long)}, and return {@code null}
* if the result of that call is {@code true}.
*/
@Override
protected long getLastModifiedInternal(HttpServletRequest request, HandlerMethod handlerMethod) {
return -1;
}
}
public class HandlerMethod {
private final Object bean;
private final Method method;
}