Jersey/Atmosphere不能生成JSON

Question

有一个方法返回List并希望它以JSON的形式发送到客户端。获取异常“未找到Java类java.util.ArrayList，Java类型java.util.List和MIME媒体类型application/json的消息正文编写器。”

我已经添加了注释@XmlRootElement我的类声明，并添加了POJO映射参数去web.xml中，但它不工作

使用2.2.3气氛与大气 - 新泽西2.2.3

POM

<dependencies> 
     <dependency> 
      <groupId>junit</groupId> 
      <artifactId>junit</artifactId> 
      <version>3.8.1</version> 
      <scope>test</scope> 
     </dependency> 
     <dependency> 
      <groupId>org.atmosphere</groupId> 
      <artifactId>atmosphere-runtime</artifactId> 
      <version>2.2.3</version> 
     </dependency> 
     <dependency> 
      <groupId>org.atmosphere</groupId> 
      <artifactId>atmosphere-jersey</artifactId> 
      <version>2.2.3</version> 
     </dependency> 
     <dependency> 
      <groupId>javax.xml</groupId> 
      <artifactId>jaxb-api</artifactId> 
      <version>2.1</version> 
     </dependency> 
    </dependencies> 

REST的资源：

package com.foo; 

import java.util.ArrayList; 
import java.util.List; 

import javax.ws.rs.GET; 
import javax.ws.rs.Path; 
import javax.ws.rs.Produces; 
import javax.ws.rs.core.MediaType; 


@Path("currencypairs") 
@Produces(MediaType.APPLICATION_JSON) 
public class CurrencyPairs { 


    @GET 
    @Path("foo") 
    public List<Thing> getPairs() { 

     List<Thing> ret = new ArrayList<Thing>(); 
     ret.add(new Thing("CAD","USD")); 
     ret.add(new Thing("EUR", "USD")); 
     ret.add(new Thing("GBP","EUR")); 
     return ret; 
    } 
} 

事情类：

package com.foo; 

import javax.xml.bind.annotation.XmlElement; 
import javax.xml.bind.annotation.XmlRootElement; 

@XmlRootElement 
public class Thing { 

    @XmlElement 
    private String a; 
    @XmlElement 
    private String b; 

    public Thing(String a, String b) 
    { 
     this.setA(a); 
     this.setB(b); 
    } 

    public String getA() { 
     return a; 
    } 

    public void setA(String a) { 
     this.a = a; 
    } 

    public String getB() { 
     return b; 
    } 

    public void setB(String b) { 
     this.b = b; 
    } 
} 

的web.xml

<?xml version="1.0" encoding="UTF-8"?> 

<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" 
    xmlns:j2ee="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" 
    xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2.5.xsd"> 

    <description>AtmosphereServlet</description> 
    <display-name>AtmosphereServlet</display-name> 
    <context-param> 
     <param-name>resteasy.scan</param-name> 
     <param-value>false</param-value> 
    </context-param> 
    <context-param> 
     <param-name>resteasy.scan.providers</param-name> 
     <param-value>false</param-value> 
    </context-param> 
    <context-param> 
     <param-name>resteasy.scan.resources</param-name> 
     <param-value>false</param-value> 
    </context-param> 
    <servlet> 
     <description>AtmosphereServlet</description> 
     <servlet-name>AtmosphereServlet</servlet-name> 
     <servlet-class>org.atmosphere.cpr.AtmosphereServlet</servlet-class> 
     <!-- If you want to use Servlet 3.0 --> 
     <async-supported>true</async-supported> 
     <!-- List of init-param --> 
     <init-param> 
      <param-name>com.sun.jersey.config.property.packages</param-name> 
      <param-value>com.foo</param-value> 
     </init-param> 
     <init-param> 
      <param-name>com.sun.jersey.api.json.POJOMappingFeature</param-name> 
      <param-value>true</param-value> 
     </init-param> 
     <load-on-startup>1</load-on-startup> 
    </servlet> 
    <servlet-mapping> 
     <servlet-name>AtmosphereServlet</servlet-name> 
     <!-- Any mapping --> 
     <url-pattern>/rest/*</url-pattern> 
    </servlet-mapping> 
</web-app> 

Answer 1

添加jersey-json-1.6.jar到你的依赖。

<dependency> 
    <groupId>com.sun.jersey</groupId> 
    <artifactId>jersey-json</artifactId> 
    <version>1.6</version> 
</dependency>