在使用jersey框架搭建服务时,经常会报出如下异常:
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:1331) at com.sun.jersey.server.impl.application.WebApplicationImpl.access$700(WebApplicationImpl.java:168) at com.sun.jersey.server.impl.application.WebApplicationImpl$13.f(WebApplicationImpl.java:774) at com.sun.jersey.server.impl.application.WebApplicationImpl$13.f(WebApplicationImpl.java:770) at com.sun.jersey.spi.inject.Errors.processWithErrors(Errors.java:193) at com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:770) at com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:765) at com.sun.jersey.spi.container.servlet.ServletContainer.initiate(ServletContainer.java:489) at com.sun.jersey.spi.container.servlet.ServletContainer$InternalWebComponent.initiate(ServletContainer.java:319) at com.sun.jersey.spi.container.servlet.WebComponent.load(WebComponent.java:605) at com.sun.jersey.spi.container.servlet.WebComponent.init(WebComponent.java:210) at com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:374) at com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:557) at javax.servlet.GenericServlet.init(GenericServlet.java:212) at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1206) at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1026) at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4421) at org.apache.catalina.core.StandardContext.start(StandardContext.java:4734) at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:799) at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:779) at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:601) at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1079) at org.apache.catalina.startup.HostConfig.deployDirectories(HostConfig.java:1002) at org.apache.catalina.startup.HostConfig.deployApps(HostConfig.java:506) at org.apache.catalina.startup.HostConfig.start(HostConfig.java:1317) at org.apache.catalina.startup.HostConfig.lifecycleEvent(HostConfig.java:324) at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:142) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1065) at org.apache.catalina.core.StandardHost.start(StandardHost.java:840) at org.apache.catalina.core.ContainerBase.start(ContainerBase.java:1057) at org.apache.catalina.core.StandardEngine.start(StandardEngine.java:463) at org.apache.catalina.core.StandardService.start(StandardService.java:525) at org.apache.catalina.core.StandardServer.start(StandardServer.java:754) at org.apache.catalina.startup.Catalina.start(Catalina.java:595) at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39) at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25) at java.lang.reflect.Method.invoke(Method.java:597) at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:289) at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:414)
下面是出现这种异常的几种情况
1、在不与spring整合,而是直接使用jersey搭建服务时,如果只在web.xml 中配置了如下代码:
<servlet>
<servlet-name>abc</servlet-name>
<servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>abc</servlet-name>
<url-pattern>/services/*</url-pattern>
</servlet-mapping>
此时启动tomcat,会报出上面的异常,原因是实例张不包含任何启动资源的类,你要确保实例已经创建,例如:
@Path("abc") @Produces("application/xml") @Consumes("application/xml") public class Abc { @POST @Produces("application/xml") @Consumes("application/xml") public void abc(){ } }
这样再启动,就可以了。
2、在与spring整合中时,如果出现如上异常,原因可能是:
1)缺少spring-jersey.jar包
将spring-jersey.jar包添加到工程lib下,然后修改下web.xml配置文件
<servlet>
<servlet-name>abc</servlet-name>
<servlet-class>com.sun.jersey.spi.spring.container.servlet.SpringServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>abc</servlet-name>
<url-pattern>/services/*</url-pattern>
</servlet-mapping>
然后再重新启动tomcat,就可以了。
2)如果按照1)操作完成后,tomcat启动仍然报上面的异常,此时需要在web.xml中在重新添加点配置信息(红色部分):
<servlet>
<servlet-name>abc</servlet-name>
<servlet-class>com.sun.jersey.spi.spring.container.servlet.SpringServlet</servlet-class>
<init-param>
<param-name>com.sun.jersey.config.property.packages</param-name>
<param-value>com.xxyd.map.webservice</param-value><!--代表的是你服务端的路径,要和你的工程服务器端路径保持一致-->
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>abc</servlet-name>
<url-pattern>/services/*</url-pattern>
</servlet-mapping>
此时再启动tomcat就可以了。
当然,还有一种方式就是重新将“com.sun.jersey.spi.spring.container.servlet.SpringServlet”替换回“com.sun.jersey.spi.spring.container.servlet.SpringServlet”,但如果是这样的话,就失去了spring与jersey整合的意义了,不提倡如此解决。
这些是我最近在做项目时遇到的问题,总结一些,供以后学习使用。
但有一点让我很奇怪,百思不得其解的是,在很久之前,我用1)中的配置方式可以正常启动tomcat,但最近写的一些项目中,居然失败了,必须改用2)中的方式,之前用的是jersey-spring-1.5.jar,最近用的是jersey-spring-1.1.7.jar,不知道是不是jar包版本的问题,希望了解或知道原因的朋友给指点迷津,谢谢。