来自Basics的Jersey教程

Shi*_*esh 3 java rest jax-rs jersey java-ee

我正在使用Jersey 1.8,我所指的教程很安静.什么都行不通.我指的是这里给出的教程

并获得一个未找到的类异常.根据教程,我创建了Java类,并配置了我的web.xml.它向我展示了一个例外,我没有办法解决这个问题.我想有一个完整的泽西实施最新教程.如果有一些东西比泽西的REST实施更好,请建议.我已经开始使用基于REST的Web服务了,如果你可以建议我从哪里开始(我只对REST感兴趣),我将不胜感激.下面是我用eclipse编写和编译的代码.

Hello.java

import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
@Path("/hello")
public class Hello {

    //This method prints the Plain Text
    @GET
    @Produces(MediaType.TEXT_PLAIN)
    public String sayPlainTextHello()
    {
        return "Hello Jersey";
    }

    //This is the XML request output

    @GET
    @Produces(MediaType.TEXT_XML)
    public String sayXMLHello()
    {
        return "<?xml version=\"1.0\"?>" + "<hello> Hello Jersey" + "</hello>";
    }

    //This result is produced if HTML is requested

    @GET
    @Produces(MediaType.TEXT_HTML)
    public String sayHTMLHello()
    {
        return "<html> " + "<title>" + "Hello Jersey" + "</title>"
        + "<body><h1>" + "Hello Jersey" + "</body></h1>" + "</html> ";
    }

}
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web.xml如下

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" id="WebApp_ID" version="2.5">
  <display-name>RESTFullApp</display-name>
  <servlet>
  <servlet-name>JerseyRESTService</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>RESTFullApp</param-value>
  </init-param>
  <load-on-startup>1</load-on-startup>
  </servlet>
  <servlet-mapping>
  <servlet-name>JerseyRESTService</servlet-name>
  <url-pattern>/rest/*</url-pattern>
  </servlet-mapping>
<!--  <welcome-file-list>-->
<!--    <welcome-file>index.html</welcome-file>-->
<!--    <welcome-file>index.htm</welcome-file>-->
<!--    <welcome-file>index.jsp</welcome-file>-->
<!--    <welcome-file>default.html</welcome-file>-->
<!--    <welcome-file>default.htm</welcome-file>-->
<!--    <welcome-file>default.jsp</welcome-file>-->
<!--  </welcome-file-list>-->
</web-app>
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不,我尝试运行时得到的错误是

exception 

javax.servlet.ServletException: Servlet.init() for servlet JerseyRESTService threw exception
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
    org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)
    org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
    org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
    java.lang.Thread.run(Unknown Source)


root cause 

com.sun.jersey.api.container.ContainerException: The ResourceConfig instance does not contain any root resource classes.
    com.sun.jersey.server.impl.application.RootResourceUriRules.<init>(RootResourceUriRules.java:99)
    com.sun.jersey.server.impl.application.WebApplicationImpl._initiate(WebApplicationImpl.java:1298)
    com.sun.jersey.server.impl.application.WebApplicationImpl.access$700(WebApplicationImpl.java:169)
    com.sun.jersey.server.impl.application.WebApplicationImpl$13.f(WebApplicationImpl.java:775)
    com.sun.jersey.server.impl.application.WebApplicationImpl$13.f(WebApplicationImpl.java:771)
    com.sun.jersey.spi.inject.Errors.processWithErrors(Errors.java:193)
    com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:771)
    com.sun.jersey.server.impl.application.WebApplicationImpl.initiate(WebApplicationImpl.java:766)
    com.sun.jersey.spi.container.servlet.ServletContainer.initiate(ServletContainer.java:488)
    com.sun.jersey.spi.container.servlet.ServletContainer$InternalWebComponent.initiate(ServletContainer.java:318)
    com.sun.jersey.spi.container.servlet.WebComponent.load(WebComponent.java:609)
    com.sun.jersey.spi.container.servlet.WebComponent.init(WebComponent.java:210)
    com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:373)
    com.sun.jersey.spi.container.servlet.ServletContainer.init(ServletContainer.java:556)
    javax.servlet.GenericServlet.init(GenericServlet.java:212)
    org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:298)
    org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:857)
    org.apache.coyote.http11.Http11Protocol$Http11ConnectionHandler.process(Http11Protocol.java:588)
    org.apache.tomcat.util.net.JIoEndpoint$Worker.run(JIoEndpoint.java:489)
    java.lang.Thread.run(Unknown Source)
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Bal*_*usC 11

你并没有完全按照教程.你在这里和那里改变了一些位而没有真正理解它们代表什么 在这种特殊情况下,根据例外情况,

com.sun.jersey.api.container.ContainerException:ResourceConfig实例不包含任何根资源类.

以下init参数错误

<init-param>
   <param-name>com.sun.jersey.config.property.packages</param-name>
   <param-value>RESTFullApp</param-value>
</init-param>
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它应该引用包含服务的包.将您的服务放在一个包中,并在init param值中指定它.泽西与否,使用默认包总是一个坏习惯.

至于教程,你为什么不阅读泽西岛自己的文档?泽西维基泽西用户指南.


Rya*_*art 5

试试Jersey用户指南.它几乎总是有最新的教程.至于错误,您的web.xml声明您的资源类将位于名为"RESTFullApp"的包中.1)这是一个特殊的包名,2)我没有看到你班上的包裹声明.

编辑:对于一个工作示例,您可以在github上查看我的示例项目.如果你有git和maven,你可以克隆它并运行它

git clone git://github.com/zzantozz/testbed.git tmp
cd tmp
mvn jetty:run -pl basic-jersey
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然后访问http:// localhost:8080/basic-jersey/rest/test