java - REST 问题 com.sun.jersey.api.container.ContainerException : The ResourceConfig instance does not contain any root resource classes

Question

我正在尝试创建一个 hello 示例 REST 服务，但遇到以下错误:

SEVERE: Allocate exception for servlet jersey-serlvet
com.sun.jersey.api.container.ContainerException: The ResourceConfig instance does not contain any root resource classes.
    at com.sun.jersey.server.impl.application.RootResourceUriRules.<init>(RootResourceUriRules.java:99)
    at com.sun.jersey.server.impl.application.WebApplicationImpl._initiate(WebApplicationImpl.java:1298)
    at com.sun.jersey.server.impl.application.WebApplicationImpl.access$700(WebApplicationImpl.java:169)
    at com.sun.jersey.server.impl.application.WebApplicationImpl$13.f(WebApplicationImpl.java:775)
    at com.sun.jersey.server.impl.application.WebApplicationImpl$13.f(WebApplicationImpl.java:771)
    at com.sun.jersey.spi.inject.Errors.processWithErrors(Errors.java:193)
    at com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:771)
    at com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:766)
    at com.sun.jersey.spi.container.servlet.ServletContainer.initiate(ServletContainer.java:488)
    at com.sun.jersey.spi.container.servlet.ServletContainer$InternalWebComponent.initiate(ServletContainer.java:318)
    at com.sun.jersey.spi.container.servlet.WebComponent.load(WebComponent.java:609)
    at com.sun.jersey.spi.container.servlet.WebComponent.init(WebComponent.java:210)
    at com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:373)
    at com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:556)
    at javax.servlet.GenericServlet.init(GenericServlet.java:160)
    at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1266)
    at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1185)
    at org.apache.catalina.core.StandardWrapper.allocate(StandardWrapper.java:857)
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:136)
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169)
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472)
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168)
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98)
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927)
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407)
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:999)
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:565)
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:309)
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)

我查看了所有相关帖子以及其他博客/论坛，但无法解决该问题。

下面是我的 servlet:

package com.mkyong.rest;

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.core.Response;

@Path("/hello")
public class HelloWorldService {

    @GET
    @Path("/{param}")
    public Response getMsg(@PathParam("param") String msg) {

        String output = "Jersey say : " + msg;

        return Response.status(200).entity(output).build();

    }

}

web.xml 文件:

http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd"> 安静的 Web 应用程序

<servlet>
    <servlet-name>jersey-serlvet</servlet-name>
    <servlet-class>
                 com.sun.jersey.spi.container.servlet.ServletContainer
            </servlet-class>
    <init-param>
         <param-name>com.sun.jersey.config.property.packages</param-name>
         <param-value>com.mkyong.rest</param-value>
    </init-param>
    <load-on-startup>1</load-on-startup>
</servlet>

<servlet-mapping>
    <servlet-name>jersey-serlvet</servlet-name>
    <url-pattern>/rest/*</url-pattern>
</servlet-mapping>

和项目结构:

当我尝试访问网址时收到错误:http://localhost:8090/RESTfulExample/rest/hello/test

我已经尝试了几个小时来解决这个问题，但没有成功。有人看到我的项目中有错误吗？

谢谢

Answer 1

我也遇到了同样的问题；在 Eclipse 中尝试[Project > Clean ...]并重新启动服务器。