Java 从嵌入式 Jetty 中的备用路径提供静态文件

Serving static files from alternate path in embedded Jetty

提问by user3034643

I'm trying to create an embedded jetty server with both a custom servlet that serves some dynamic data, and default servlet that will serve some images. I have the custom servlet working, but I can't figure out how to add a default servlet to serve the image files.

我正在尝试使用提供一些动态数据的自定义 servlet 和将提供一些图像的默认 servlet 创建一个嵌入式码头服务器。我有自定义 servlet 工作，但我不知道如何添加默认 servlet 来提供图像文件。

This is what I have...

这就是我所拥有的...

private void setUpServer(ServerOptions options){
    s = new Server(options.getPort());
    this.options = options;
    context = new ServletContextHandler(ServletContextHandler.SESSIONS);
    context.setContextPath("/");
    s.setHandler(context);
    context.addServlet(new ServletHolder(new DataServlet()), "/data/*");
    context.addServlet(new ServletHolder(new DefaultServlet()), "/pictures/*");
}

I can't figure out how to configure the DefaultServlet to work as a file server and still have the custom DataServelet still work.

我不知道如何将 DefaultServlet 配置为作为文件服务器工作并且仍然让自定义 DataServelet 仍然工作。

Does anyone have any ideas?

有没有人有任何想法？

采纳答案by Joakim Erdfelt

What you need:

你需要什么：

1. A DefaultServlet at "/" (recommended, it is a requirement of the servlet spec)
   • this should be at named dispatcher of "default" (another requirement of servlet spec)
2. An alternate DefaultServlet with your custom static content, configured via init-params
   • Using a different named dispatcher than "default" (to avoid a name collision between other servlet spec features)
   • You can use the ServletHolder.setInitParameter(name,value)to accomplish this
   • Be sure you set the pathInfoOnlyparameter to true(to get around special cases for "default" named dispatchers)
3. A servlet of your own, serving dynamic content.

1. “/”处的 DefaultServlet（推荐，这是 servlet 规范的要求）
   • 这应该在“默认”的命名调度程序（servlet规范的另一个要求）
2. 带有自定义静态内容的备用 DefaultServlet，通过 init-params 配置
   • 使用与“默认”不同的命名调度程序（以避免其他 servlet 规范功能之间的名称冲突）
   • 您可以使用ServletHolder.setInitParameter(name,value)来完成此操作
   • 确保将pathInfoOnly参数设置为true（以避开“默认”命名调度程序的特殊情况）
3. 您自己的 servlet，提供动态内容。

AltDefaultServlet.java

AltDefaultServlet.java

package jetty.demo;

import org.eclipse.jetty.server.Server;
import org.eclipse.jetty.server.ServerConnector;
import org.eclipse.jetty.servlet.DefaultServlet;
import org.eclipse.jetty.servlet.ServletContextHandler;
import org.eclipse.jetty.servlet.ServletHolder;

public class AltDefaultServlet
{
    public static void main(String[] args)
    {
        System.setProperty("org.eclipse.jetty.LEVEL","INFO");

        Server server = new Server();
        ServerConnector connector = new ServerConnector(server);
        connector.setPort(8080);
        server.addConnector(connector);

        // The filesystem paths we will map
        String homePath = System.getProperty("user.home");
        String pwdPath = System.getProperty("user.dir");

        // Setup the basic application "context" for this application at "/"
        // This is also known as the handler tree (in jetty speak)
        ServletContextHandler context = new ServletContextHandler(ServletContextHandler.SESSIONS);
        context.setBaseResource(Resource.newResource(pwdPath));
        context.setContextPath("/");
        server.setHandler(context);

        // add a simple Servlet at "/dynamic/*"
        ServletHolder holderDynamic = new ServletHolder("dynamic", DynamicServlet.class);
        context.addServlet(holderDynamic, "/dynamic/*");

        // add special pathspec of "/home/" content mapped to the homePath
        ServletHolder holderHome = new ServletHolder("static-home", DefaultServlet.class);
        holderHome.setInitParameter("resourceBase",homePath);
        holderHome.setInitParameter("dirAllowed","true");
        holderHome.setInitParameter("pathInfoOnly","true");
        context.addServlet(holderHome,"/home/*");

        // Lastly, the default servlet for root content (always needed, to satisfy servlet spec)
        // It is important that this is last.
        ServletHolder holderPwd = new ServletHolder("default", DefaultServlet.class);
        holderPwd.setInitParameter("dirAllowed","true");
        context.addServlet(holderPwd,"/");

        try
        {
            server.start();
            server.dump(System.err);
            server.join();
        }
        catch (Throwable t)
        {
            t.printStackTrace(System.err);
        }
    }

}