Java tutorial
/* * Copyright 2014-2019 the original author or authors. * * Licensed under the Apache License, Version 2.0 (the "License"); * you may not use this file except in compliance with the License. * You may obtain a copy of the License at * * https://www.apache.org/licenses/LICENSE-2.0 * * Unless required by applicable law or agreed to in writing, software * distributed under the License is distributed on an "AS IS" BASIS, * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. * See the License for the specific language governing permissions and * limitations under the License. */ package org.springframework.data.rest.webmvc; import java.io.BufferedReader; import java.io.IOException; import java.io.UnsupportedEncodingException; import java.lang.reflect.Method; import java.net.URI; import java.security.Principal; import java.util.ArrayList; import java.util.Collection; import java.util.Collections; import java.util.Enumeration; import java.util.List; import java.util.Locale; import java.util.Map; import java.util.Set; import javax.servlet.AsyncContext; import javax.servlet.DispatcherType; import javax.servlet.RequestDispatcher; import javax.servlet.ServletContext; import javax.servlet.ServletException; import javax.servlet.ServletInputStream; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import javax.servlet.http.Cookie; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletRequestWrapper; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import javax.servlet.http.Part; import org.springframework.data.rest.core.config.RepositoryRestConfiguration; import org.springframework.data.util.ProxyUtils; import org.springframework.http.HttpHeaders; import org.springframework.http.MediaType; import org.springframework.util.Assert; import org.springframework.util.StringUtils; import org.springframework.web.method.HandlerMethod; import org.springframework.web.servlet.mvc.condition.PatternsRequestCondition; import org.springframework.web.servlet.mvc.condition.ProducesRequestCondition; import org.springframework.web.servlet.mvc.method.RequestMappingInfo; import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping; import org.springframework.web.util.UrlPathHelper; /** * A {@link RequestMappingHandlerMapping} that augments the request mappings * * @author Oliver Gierke */ public class BasePathAwareHandlerMapping extends RequestMappingHandlerMapping { private static final UrlPathHelper URL_PATH_HELPER = new UrlPathHelper(); private final RepositoryRestConfiguration configuration; private String prefix; /** * Creates a new {@link BasePathAwareHandlerMapping} using the given {@link RepositoryRestConfiguration}. * * @param configuration must not be {@literal null}. */ public BasePathAwareHandlerMapping(RepositoryRestConfiguration configuration) { Assert.notNull(configuration, "RepositoryRestConfiguration must not be null!"); this.configuration = configuration; } /* * (non-Javadoc) * @see org.springframework.web.servlet.handler.AbstractHandlerMethodMapping#lookupHandlerMethod(java.lang.String, javax.servlet.http.HttpServletRequest) */ @Override protected HandlerMethod lookupHandlerMethod(String lookupPath, HttpServletRequest request) throws Exception { List<MediaType> mediaTypes = new ArrayList<MediaType>(); boolean defaultFound = false; for (MediaType mediaType : MediaType.parseMediaTypes(request.getHeader(HttpHeaders.ACCEPT))) { MediaType rawtype = mediaType.removeQualityValue(); if (rawtype.equals(configuration.getDefaultMediaType())) { defaultFound = true; } if (!rawtype.equals(MediaType.ALL)) { mediaTypes.add(mediaType); } } if (!defaultFound) { mediaTypes.add(configuration.getDefaultMediaType()); } return super.lookupHandlerMethod(lookupPath, new CustomAcceptHeaderHttpServletRequest(request, mediaTypes)); } /* * (non-Javadoc) * @see org.springframework.web.servlet.handler.AbstractHandlerMapping#hasCorsConfigurationSource(java.lang.Object) */ @Override protected boolean hasCorsConfigurationSource(Object handler) { return true; } /* * (non-Javadoc) * @see org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping#getMappingForMethod(java.lang.reflect.Method, java.lang.Class) */ @Override protected RequestMappingInfo getMappingForMethod(Method method, Class<?> handlerType) { RequestMappingInfo info = super.getMappingForMethod(method, handlerType); if (info == null) { return null; } PatternsRequestCondition patternsCondition = customize(info.getPatternsCondition(), prefix); ProducesRequestCondition producesCondition = customize(info.getProducesCondition()); return new RequestMappingInfo(patternsCondition, info.getMethodsCondition(), info.getParamsCondition(), info.getHeadersCondition(), info.getConsumesCondition(), producesCondition, info.getCustomCondition()); } /** * Customize the given {@link PatternsRequestCondition} and prefix. * * @param condition will never be {@literal null}. * @param prefix will never be {@literal null}. * @return */ protected PatternsRequestCondition customize(PatternsRequestCondition condition, String prefix) { Set<String> patterns = condition.getPatterns(); String[] augmentedPatterns = new String[patterns.size()]; int count = 0; for (String pattern : patterns) { augmentedPatterns[count++] = prefix.concat(pattern); } return new PatternsRequestCondition(augmentedPatterns, getUrlPathHelper(), getPathMatcher(), useSuffixPatternMatch(), useTrailingSlashMatch(), getFileExtensions()); } /** * Customize the given {@link ProducesRequestCondition}. Default implementation returns the condition as is. * * @param condition will never be {@literal null}. * @return */ protected ProducesRequestCondition customize(ProducesRequestCondition condition) { return condition; } /* * (non-Javadoc) * @see org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping#isHandler(java.lang.Class) */ @Override protected boolean isHandler(Class<?> beanType) { Class<?> type = ProxyUtils.getUserClass(beanType); return type.isAnnotationPresent(BasePathAwareController.class); } /* * (non-Javadoc) * @see org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping#afterPropertiesSet() */ @Override public void afterPropertiesSet() { URI baseUri = configuration.getBaseUri(); if (baseUri.isAbsolute()) { HttpServletRequest request = new UriAwareHttpServletRequest(getServletContext(), baseUri); this.prefix = URL_PATH_HELPER.getPathWithinApplication(request); } else { this.prefix = baseUri.toString(); } super.afterPropertiesSet(); } private static class UriAwareHttpServletRequest implements HttpServletRequest { private final ServletContext context; private final String path; /** * @param context * @param uri */ public UriAwareHttpServletRequest(ServletContext context, URI uri) { this.context = context; this.path = uri.getPath(); } /* * (non-Javadoc) * @see javax.servlet.ServletRequest#getAttribute(java.lang.String) */ @Override public Object getAttribute(String name) { return null; } @Override public Enumeration<String> getAttributeNames() { throw new UnsupportedOperationException(); } /* * (non-Javadoc) * @see javax.servlet.ServletRequest#getCharacterEncoding() */ @Override public String getCharacterEncoding() { return null; } @Override public void setCharacterEncoding(String env) throws UnsupportedEncodingException { throw new UnsupportedOperationException(); } @Override public int getContentLength() { throw new UnsupportedOperationException(); } @Override public String getContentType() { throw new UnsupportedOperationException(); } @Override public ServletInputStream getInputStream() throws IOException { throw new UnsupportedOperationException(); } @Override public String getParameter(String name) { throw new UnsupportedOperationException(); } @Override public Enumeration<String> getParameterNames() { throw new UnsupportedOperationException(); } @Override public String[] getParameterValues(String name) { throw new UnsupportedOperationException(); } @Override public Map<String, String[]> getParameterMap() { throw new UnsupportedOperationException(); } @Override public String getProtocol() { throw new UnsupportedOperationException(); } @Override public String getScheme() { throw new UnsupportedOperationException(); } @Override public String getServerName() { throw new UnsupportedOperationException(); } @Override public int getServerPort() { throw new UnsupportedOperationException(); } @Override public BufferedReader getReader() throws IOException { throw new UnsupportedOperationException(); } @Override public String getRemoteAddr() { throw new UnsupportedOperationException(); } @Override public String getRemoteHost() { throw new UnsupportedOperationException(); } @Override public void setAttribute(String name, Object o) { throw new UnsupportedOperationException(); } @Override public void removeAttribute(String name) { throw new UnsupportedOperationException(); } @Override public Locale getLocale() { throw new UnsupportedOperationException(); } @Override public Enumeration<Locale> getLocales() { throw new UnsupportedOperationException(); } @Override public boolean isSecure() { throw new UnsupportedOperationException(); } @Override public RequestDispatcher getRequestDispatcher(String path) { throw new UnsupportedOperationException(); } @Override public String getRealPath(String path) { throw new UnsupportedOperationException(); } @Override public int getRemotePort() { throw new UnsupportedOperationException(); } @Override public String getLocalName() { throw new UnsupportedOperationException(); } @Override public String getLocalAddr() { throw new UnsupportedOperationException(); } @Override public int getLocalPort() { throw new UnsupportedOperationException(); } /* * (non-Javadoc) * @see javax.servlet.ServletRequest#getServletContext() */ @Override public ServletContext getServletContext() { return context; } @Override public AsyncContext startAsync() throws IllegalStateException { throw new UnsupportedOperationException(); } @Override public AsyncContext startAsync(ServletRequest servletRequest, ServletResponse servletResponse) throws IllegalStateException { throw new UnsupportedOperationException(); } @Override public boolean isAsyncStarted() { throw new UnsupportedOperationException(); } @Override public boolean isAsyncSupported() { throw new UnsupportedOperationException(); } @Override public AsyncContext getAsyncContext() { throw new UnsupportedOperationException(); } @Override public DispatcherType getDispatcherType() { throw new UnsupportedOperationException(); } @Override public String getAuthType() { throw new UnsupportedOperationException(); } @Override public Cookie[] getCookies() { throw new UnsupportedOperationException(); } @Override public long getDateHeader(String name) { throw new UnsupportedOperationException(); } @Override public String getHeader(String name) { throw new UnsupportedOperationException(); } @Override public Enumeration<String> getHeaders(String name) { throw new UnsupportedOperationException(); } @Override public Enumeration<String> getHeaderNames() { throw new UnsupportedOperationException(); } @Override public int getIntHeader(String name) { throw new UnsupportedOperationException(); } @Override public String getMethod() { throw new UnsupportedOperationException(); } @Override public String getPathInfo() { throw new UnsupportedOperationException(); } @Override public String getPathTranslated() { throw new UnsupportedOperationException(); } /* * (non-Javadoc) * @see javax.servlet.http.HttpServletRequest#getContextPath() */ @Override public String getContextPath() { return context.getContextPath(); } @Override public String getQueryString() { throw new UnsupportedOperationException(); } @Override public String getRemoteUser() { throw new UnsupportedOperationException(); } @Override public boolean isUserInRole(String role) { throw new UnsupportedOperationException(); } @Override public Principal getUserPrincipal() { throw new UnsupportedOperationException(); } @Override public String getRequestedSessionId() { throw new UnsupportedOperationException(); } /* * (non-Javadoc) * @see javax.servlet.http.HttpServletRequest#getRequestURI() */ @Override public String getRequestURI() { return path; } @Override public StringBuffer getRequestURL() { throw new UnsupportedOperationException(); } @Override public String getServletPath() { throw new UnsupportedOperationException(); } @Override public HttpSession getSession(boolean create) { throw new UnsupportedOperationException(); } @Override public HttpSession getSession() { throw new UnsupportedOperationException(); } @Override public boolean isRequestedSessionIdValid() { throw new UnsupportedOperationException(); } @Override public boolean isRequestedSessionIdFromCookie() { throw new UnsupportedOperationException(); } @Override public boolean isRequestedSessionIdFromURL() { throw new UnsupportedOperationException(); } @Override public boolean isRequestedSessionIdFromUrl() { throw new UnsupportedOperationException(); } @Override public boolean authenticate(HttpServletResponse response) throws IOException, ServletException { throw new UnsupportedOperationException(); } @Override public void login(String username, String password) throws ServletException { throw new UnsupportedOperationException(); } @Override public void logout() throws ServletException { throw new UnsupportedOperationException(); } @Override public Collection<Part> getParts() throws IOException, ServletException { throw new UnsupportedOperationException(); } @Override public Part getPart(String name) throws IOException, ServletException { throw new UnsupportedOperationException(); } } /** * {@link HttpServletRequest} that exposes the given media types for the {@code Accept} header. * * @author Oliver Gierke */ static class CustomAcceptHeaderHttpServletRequest extends HttpServletRequestWrapper { private final List<MediaType> acceptMediaTypes; private final List<String> acceptMediaTypeStrings; /** * Creates a new {@link CustomAcceptHeaderHttpServletRequest} for the given delegate {@link HttpServletRequest} and * the list of {@link MediaType}. * * @param request must not be {@literal null}. * @param acceptMediaTypes must not be {@literal null} or empty. */ public CustomAcceptHeaderHttpServletRequest(HttpServletRequest request, List<MediaType> acceptMediaTypes) { super(request); Assert.notEmpty(acceptMediaTypes, "MediaTypes must not be empty!"); this.acceptMediaTypes = acceptMediaTypes; List<String> acceptMediaTypeStrings = new ArrayList<String>(acceptMediaTypes.size()); for (MediaType mediaType : acceptMediaTypes) { acceptMediaTypeStrings.add(mediaType.toString()); } this.acceptMediaTypeStrings = acceptMediaTypeStrings; } /* * (non-Javadoc) * @see javax.servlet.http.HttpServletRequestWrapper#getHeader(java.lang.String) */ @Override public String getHeader(String name) { if (HttpHeaders.ACCEPT.equalsIgnoreCase(name) && acceptMediaTypes != null) { return StringUtils.collectionToCommaDelimitedString(acceptMediaTypes); } return super.getHeader(name); } /* * (non-Javadoc) * @see javax.servlet.http.HttpServletRequestWrapper#getHeaders(java.lang.String) */ @Override public Enumeration<String> getHeaders(String name) { if (HttpHeaders.ACCEPT.equalsIgnoreCase(name) && acceptMediaTypes != null) { return Collections.enumeration(acceptMediaTypeStrings); } return super.getHeaders(name); } } }