具有 Angular URL 重写功能的嵌入式 Jetty

在 Servlet 世界中实现此目的的唯一方法是让错误页面处理 404 状态代码并自行发出重定向。这只能在特定的 Web 应用程序中完成，而不能从通用重写处理例程中完成。为什么？那么，“如果请求的资源不存在，则使用index.html”是关键。会发生什么。输入了 web 应用程序，但没有匹配的 url-pattern，因此使用默认的 url-pattern (of )。"/"默认 url 模式映射到所谓的“默认 Servlet”默认 Servlet 负责在 Web 应用程序的基础资源中查找匹配的资源，并将该内容作为静态资源请求返回。如果静态资源不存在，并且请求是针对目录（例如：/js/然后使用欢迎文件列表来查找欢迎文件。（此列表在中配置WEB-INF/web.xml）<welcome-file-list> <welcome-file>index.html</welcome-file> <welcome-file>index.htm</welcome-file> <welcome-file>index.jsp</welcome-file></welcome-file-list>如果静态资源仍然不存在，则将其作为 404 响应进行处理。同时，servlet 规范的错误页面处理例程启动。这将导致在您的WEB-INF/web.xml.<servlet> <servletname>404Handler</servlet-name> <servlet-class>com.acme.My404Servlet</servlet-class></servlet><servlet-mapping> <servlet-name>404Handler</servlet-name> <url-pattern>/404status</url-pattern></servlet-mapping><error-page> <error-code>404</error-code> <location>/404status</location></error-page>该路径可以是 servlet、静态资源、jsp 等。几乎可以是任何可以通过路径引用的内容。如果它是 servlet（或 jsp），您可以通过请求属性询问原始请求，以了解处理此错误的原因。嵌入式码头中的一个例子是......package jetty.errors;import java.io.IOException;import java.nio.file.Files;import java.nio.file.Path;import java.nio.file.Paths;import javax.servlet.DispatcherType;import javax.servlet.RequestDispatcher;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import org.eclipse.jetty.server.Server;import org.eclipse.jetty.server.handler.DefaultHandler;import org.eclipse.jetty.server.handler.HandlerList;import org.eclipse.jetty.servlet.DefaultServlet;import org.eclipse.jetty.servlet.ErrorPageErrorHandler;import org.eclipse.jetty.servlet.ServletContextHandler;import org.eclipse.jetty.servlet.ServletHolder;import org.eclipse.jetty.util.resource.PathResource;public class EmbeddedWelcomeErrorDemo{ public static void main(String[] args) throws Exception { Server server = new Server(8080); String baseDir = System.getProperty("user.home"); if (args.length > 0) baseDir = args[0]; Path basePath = Paths.get(baseDir); if (!Files.exists(basePath) || !Files.isDirectory(basePath)) { throw new IOException("Not a valid directory: " + basePath); } ServletContextHandler context = new ServletContextHandler(); context.setContextPath("/"); context.setBaseResource(new PathResource(basePath)); context.setWelcomeFiles(new String[]{ "index.html" }); // Add error page mapping for context context.addServlet(ErrorHandling.class, "/errorpage"); ErrorPageErrorHandler errorMapper = new ErrorPageErrorHandler(); errorMapper.addErrorPage(404, "/errorpage"); context.setErrorHandler(errorMapper); // to handle static resources against base resource (always last) // always named "default" (per spec) ServletHolder defaultHolder = new ServletHolder("default", DefaultServlet.class); // assigned to default url-pattern of "/" (per spec) context.addServlet(defaultHolder, "/"); HandlerList handlers = new HandlerList(); handlers.addHandler(context); handlers.addHandler(new DefaultHandler()); // for non-context errors server.setHandler(handlers); server.start(); server.join(); } public static class ErrorHandling extends HttpServlet { @Override protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { if (req.getDispatcherType() != DispatcherType.ERROR) { // we didn't get here from a error dispatch. // somebody attempted to use this servlet directly. resp.setStatus(404); return; } String requestedResource = (String)req.getAttribute(RequestDispatcher.ERROR_REQUEST_URI); log("[ErrorHandling] Requested resource was " + requestedResource); int statusCode = (int)req.getAttribute(RequestDispatcher.ERROR_STATUS_CODE); switch (statusCode) { case 404: // let handle it by a redirect resp.sendRedirect("/"); break; default: // pass the other errors through resp.setStatus(statusCode); break; } } }}发生的情况的一些例子。$ mkdir $HOME/tmp-base$ mdkir css$ echo "this is the index.html" > index.html$ echo "this is my other html" > myother.html$ echo "this is my fancy css" > css/main.css然后使用命令行运行服务器示例到该目录$ java ... jetty.errors.EmbeddedWelcomeErrorDemo $HOME/tmp-base2019-09-24 14:17:55.540:INFO::main: Logging initialized @190ms to org.eclipse.jetty.util.log.StdErrLog2019-09-24 14:17:55.621:INFO:oejs.Server:main: jetty-9.4.20.v20190813; built: 2019-08-13T21:28:18.144Z; git: 84700530e645e812b336747464d6fbbf370c9a20; jvm 1.8.0_202-b082019-09-24 14:17:55.661:INFO:oejsh.ContextHandler:main: Started o.e.j.s.ServletContextHandler@7921b0a2{/,file:///home/joakim/tmp-base/,AVAILABLE}2019-09-24 14:17:55.674:INFO:oejs.AbstractConnector:main: Started ServerConnector@7cef4e59{HTTP/1.1,[http/1.1]}{0.0.0.0:8080}2019-09-24 14:17:55.674:INFO:oejs.Server:main: Started @325ms然后提出一些要求...$ curl -L -vv http://localhost:8080/* Trying ::1...* TCP_NODELAY set* Connected to localhost (::1) port 8080 (#0)> GET / HTTP/1.1> Host: localhost:8080> User-Agent: curl/7.58.0> Accept: */*> < HTTP/1.1 200 OK< Date: Tue, 24 Sep 2019 19:26:28 GMT< Last-Modified: Tue, 24 Sep 2019 19:12:21 GMT< Content-Type: text/html< Accept-Ranges: bytes< Content-Length: 23< Server: Jetty(9.4.20.v20190813)< this is the index.html* Connection #0 to host localhost left intact这是受欢迎的文件处理$ curl -L -vv http://localhost:8080/myother.html* Trying ::1...* TCP_NODELAY set* Connected to localhost (::1) port 8080 (#0)> GET /myother.html HTTP/1.1> Host: localhost:8080> User-Agent: curl/7.58.0> Accept: */*> < HTTP/1.1 200 OK< Date: Tue, 24 Sep 2019 19:21:10 GMT< Last-Modified: Tue, 24 Sep 2019 19:13:46 GMT< Content-Type: text/html< Accept-Ranges: bytes< Content-Length: 22< Server: Jetty(9.4.20.v20190813)< This is my other html* Connection #0 to host localhost left intact这是正常的静态文件服务$ curl -L -vv http://localhost:8080/css/main.css* Trying ::1...* TCP_NODELAY set* Connected to localhost (::1) port 8080 (#0)> GET /css/main.css HTTP/1.1> Host: localhost:8080> User-Agent: curl/7.58.0> Accept: */*> < HTTP/1.1 200 OK< Date: Tue, 24 Sep 2019 19:22:22 GMT< Last-Modified: Tue, 24 Sep 2019 19:22:16 GMT< Content-Type: text/css< Accept-Ranges: bytes< Content-Length: 21< Server: Jetty(9.4.20.v20190813)< this is my fancy css* Connection #0 to host localhost left intact这是正常的静态文件服务如果我向不存在的资源或目录发出一些请求......$ curl -L -vv http://localhost:8080/css/bogus.css* Trying ::1...* TCP_NODELAY set* Connected to localhost (::1) port 8080 (#0)> GET /css/bogus.css HTTP/1.1> Host: localhost:8080> User-Agent: curl/7.58.0> Accept: */*> < HTTP/1.1 302 Found< Date: Tue, 24 Sep 2019 19:22:46 GMT< Location: http://localhost:8080/< Content-Length: 0< Server: Jetty(9.4.20.v20190813)< * Connection #0 to host localhost left intact* Issue another request to this URL: 'http://localhost:8080/'* Found bundle for host localhost: 0x5647e1581a50 [can pipeline]* Re-using existing connection! (#0) with host localhost* Connected to localhost (::1) port 8080 (#0)> GET / HTTP/1.1> Host: localhost:8080> User-Agent: curl/7.58.0> Accept: */*> < HTTP/1.1 200 OK< Date: Tue, 24 Sep 2019 19:22:46 GMT< Last-Modified: Tue, 24 Sep 2019 19:12:21 GMT< Content-Type: text/html< Accept-Ranges: bytes< Content-Length: 23< Server: Jetty(9.4.20.v20190813)< this is the index.html* Connection #0 to host localhost left intact这是由ErrorHandlingservlet处理的$ curl -L -vv http://localhost:8080/this/directory/does/not/exist* Trying ::1...* TCP_NODELAY set* Connected to localhost (::1) port 8080 (#0)> GET /this/directory/does/not/exist HTTP/1.1> Host: localhost:8080> User-Agent: curl/7.58.0> Accept: */*> < HTTP/1.1 302 Found< Date: Tue, 24 Sep 2019 19:23:02 GMT< Location: http://localhost:8080/< Content-Length: 0< Server: Jetty(9.4.20.v20190813)< * Connection #0 to host localhost left intact* Issue another request to this URL: 'http://localhost:8080/'* Found bundle for host localhost: 0x561eefa8b020 [can pipeline]* Re-using existing connection! (#0) with host localhost* Connected to localhost (::1) port 8080 (#0)> GET / HTTP/1.1> Host: localhost:8080> User-Agent: curl/7.58.0> Accept: */*> < HTTP/1.1 200 OK< Date: Tue, 24 Sep 2019 19:23:02 GMT< Last-Modified: Tue, 24 Sep 2019 19:12:21 GMT< Content-Type: text/html< Accept-Ranges: bytes< Content-Length: 23< Server: Jetty(9.4.20.v20190813)< this is the index.html* Connection #0 to host localhost left intact这是由ErrorHandlingservlet处理的[joakim@hyperion tmp]$ curl -L -vv http://localhost:8080/non-existant.jpeg* Trying ::1...* TCP_NODELAY set* Connected to localhost (::1) port 8080 (#0)> GET /non-existant.jpeg HTTP/1.1> Host: localhost:8080> User-Agent: curl/7.58.0> Accept: */*> < HTTP/1.1 302 Found< Date: Tue, 24 Sep 2019 19:21:18 GMT< Location: http://localhost:8080/< Content-Length: 0< Server: Jetty(9.4.20.v20190813)< * Connection #0 to host localhost left intact* Issue another request to this URL: 'http://localhost:8080/'* Found bundle for host localhost: 0x563f476b6a50 [can pipeline]* Re-using existing connection! (#0) with host localhost* Connected to localhost (::1) port 8080 (#0)> GET / HTTP/1.1> Host: localhost:8080> User-Agent: curl/7.58.0> Accept: */*> < HTTP/1.1 200 OK< Date: Tue, 24 Sep 2019 19:21:18 GMT< Last-Modified: Tue, 24 Sep 2019 19:12:21 GMT< Content-Type: text/html< Accept-Ranges: bytes< Content-Length: 23< Server: Jetty(9.4.20.v20190813)< this is the index.html* Connection #0 to host localhost left intact

具有 Angular URL 重写功能的嵌入式 Jetty

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