1.1 --- a/src/java/de/uapcore/lightpit/AbstractLightPITServlet.java Sun Dec 17 01:45:28 2017 +0100
1.2 +++ b/src/java/de/uapcore/lightpit/AbstractLightPITServlet.java Sat Dec 23 17:28:19 2017 +0100
1.3 @@ -34,7 +34,6 @@
1.4 import java.util.HashMap;
1.5 import java.util.Map;
1.6 import java.util.Optional;
1.7 -import java.util.function.BiConsumer;
1.8 import javax.servlet.ServletException;
1.9 import javax.servlet.http.HttpServlet;
1.10 import javax.servlet.http.HttpServletRequest;
1.11 @@ -60,10 +59,16 @@
1.12 */
1.13 private Optional<LightPITModule.ELProxy> moduleInfoELProxy = Optional.empty();
1.14
1.15 +
1.16 + @FunctionalInterface
1.17 + private static interface HandlerMethod {
1.18 + ResponseType apply(HttpServletRequest t, HttpServletResponse u) throws IOException, ServletException;
1.19 + }
1.20 +
1.21 /**
1.22 * Invocation mapping gathered from the {@link RequestMapping} annotations.
1.23 */
1.24 - private final Map<HttpMethod, Map<String, BiConsumer<HttpServletRequest, HttpServletResponse>>> mappings = new HashMap<>();
1.25 + private final Map<HttpMethod, Map<String, HandlerMethod>> mappings = new HashMap<>();
1.26
1.27 /**
1.28 * Gives implementing modules access to the {@link ModuleManager}.
1.29 @@ -73,12 +78,15 @@
1.30 return (ModuleManager) getServletContext().getAttribute(ModuleManager.SC_ATTR_NAME);
1.31 }
1.32
1.33 - private void invokeMapping(Method method, HttpServletRequest req, HttpServletResponse resp) {
1.34 + private ResponseType invokeMapping(Method method, HttpServletRequest req, HttpServletResponse resp)
1.35 + throws IOException, ServletException {
1.36 try {
1.37 LOG.debug("invoke {}", method.getName());
1.38 - method.invoke(this, req, resp);
1.39 - } catch (ReflectiveOperationException ex) {
1.40 + return (ResponseType) method.invoke(this, req, resp);
1.41 + } catch (ReflectiveOperationException | ClassCastException ex) {
1.42 LOG.error(String.format("invocation of method %s failed", method.getName()), ex);
1.43 + resp.sendError(HttpServletResponse.SC_INTERNAL_SERVER_ERROR);
1.44 + return ResponseType.NONE;
1.45 }
1.46 }
1.47
1.48 @@ -88,6 +96,14 @@
1.49 moduleInfoELProxy = moduleInfo.map(LightPITModule.ELProxy::convert);
1.50
1.51 if (moduleInfo.isPresent()) {
1.52 + scanForRequestMappings();
1.53 + }
1.54 +
1.55 + LOG.trace("{} initialized", getServletName());
1.56 + }
1.57 +
1.58 + private void scanForRequestMappings() {
1.59 + try {
1.60 Method[] methods = getClass().getDeclaredMethods();
1.61 for (Method method : methods) {
1.62 Optional<RequestMapping> mapping = Optional.ofNullable(method.getAnnotation(RequestMapping.class));
1.63 @@ -104,12 +120,18 @@
1.64 );
1.65 continue;
1.66 }
1.67 -
1.68 + if (!ResponseType.class.isAssignableFrom(method.getReturnType())) {
1.69 + LOG.warn("{} is annotated with {} but has the wrong return type - 'ResponseType' required",
1.70 + method.getName(), RequestMapping.class.getSimpleName()
1.71 + );
1.72 + continue;
1.73 + }
1.74 +
1.75 Class<?>[] params = method.getParameterTypes();
1.76 if (params.length == 2
1.77 && HttpServletRequest.class.isAssignableFrom(params[0])
1.78 && HttpServletResponse.class.isAssignableFrom(params[1])) {
1.79 -
1.80 +
1.81 if (mappings.computeIfAbsent(mapping.get().method(), k -> new HashMap<>()).
1.82 putIfAbsent(mapping.get().requestPath(),
1.83 (req, resp) -> invokeMapping(method, req, resp)) != null) {
1.84 @@ -118,22 +140,22 @@
1.85 mapping.get().requestPath()
1.86 );
1.87 }
1.88 -
1.89 +
1.90 LOG.info("{} {} maps to {}",
1.91 mapping.get().method(),
1.92 mapping.get().requestPath(),
1.93 method.getName()
1.94 );
1.95 } else {
1.96 - LOG.warn("{} is annotated with {} but has the wrong signature - (HttpServletRequest,HttpServletResponse) required",
1.97 + LOG.warn("{} is annotated with {} but has the wrong parameters - (HttpServletRequest,HttpServletResponse) required",
1.98 method.getName(), RequestMapping.class.getSimpleName()
1.99 );
1.100 }
1.101 }
1.102 }
1.103 + } catch (SecurityException ex) {
1.104 + LOG.error("Scan for request mappings on declared methods failed.", ex);
1.105 }
1.106 -
1.107 - LOG.trace("{} initialized", getServletName());
1.108 }
1.109
1.110 @Override
1.111 @@ -167,29 +189,46 @@
1.112 req.getRequestDispatcher(Functions.jspPath("full.jsp")).forward(req, resp);
1.113 }
1.114
1.115 - private Optional<BiConsumer<HttpServletRequest, HttpServletResponse>> findMapping(HttpMethod method, HttpServletRequest req) {
1.116 + private Optional<HandlerMethod> findMapping(HttpMethod method, HttpServletRequest req) {
1.117 return Optional.ofNullable(mappings.get(method)).map(
1.118 (rm) -> rm.get(Optional.ofNullable(req.getPathInfo()).orElse(""))
1.119 );
1.120 }
1.121
1.122 + private void forwardAsSepcified(ResponseType type, HttpServletRequest req, HttpServletResponse resp)
1.123 + throws ServletException, IOException {
1.124 + switch (type) {
1.125 + case NONE: return;
1.126 + case HTML_FULL:
1.127 + forwardToFullView(req, resp);
1.128 + return;
1.129 + // TODO: implement remaining response types
1.130 + default:
1.131 + // this code should be unreachable
1.132 + LOG.error("ResponseType switch is not exhaustive - this is a bug!");
1.133 + throw new UnsupportedOperationException();
1.134 + }
1.135 + }
1.136 +
1.137 + private void doProcess(HttpMethod method, HttpServletRequest req, HttpServletResponse resp)
1.138 + throws ServletException, IOException {
1.139 + Optional<HandlerMethod> mapping = findMapping(method, req);
1.140 + if (mapping.isPresent()) {
1.141 + forwardAsSepcified(mapping.get().apply(req, resp), req, resp);
1.142 + } else {
1.143 + resp.sendError(HttpServletResponse.SC_NOT_FOUND);
1.144 + }
1.145 + }
1.146 +
1.147 @Override
1.148 protected final void doGet(HttpServletRequest req, HttpServletResponse resp)
1.149 throws ServletException, IOException {
1.150 -
1.151 - findMapping(HttpMethod.GET, req).ifPresent((consumer) -> consumer.accept(req, resp));
1.152 -
1.153 - // TODO: let the invoked handler decide (signature must be changed from a BiConsumer to a BiFunction)
1.154 - // TODO: we should call a default handler, if no specific mapping could be found
1.155 - forwardToFullView(req, resp);
1.156 + doProcess(HttpMethod.GET, req, resp);
1.157 }
1.158
1.159 @Override
1.160 protected final void doPost(HttpServletRequest req, HttpServletResponse resp)
1.161 throws ServletException, IOException {
1.162 -
1.163 - findMapping(HttpMethod.POST, req).ifPresent((consumer) -> consumer.accept(req, resp));
1.164 -
1.165 - forwardToFullView(req, resp);
1.166 + doProcess(HttpMethod.POST, req, resp);
1.167 }
1.168 }
