GET请求失败，JAX-RS:找不到类型为java.util.ArrayList、媒体类型为text/html的响应对象的MessageBodyWriter

我正在使用JEE7用JAX-RS构建一个示例客户机服务器。我使用的是Wildfly 10.1

我在录像中跟踪了那个家伙。以下是在应用服务器上运行的war代码：

boundary

包包含服务

package pl.devcrowd.virtual.business.chickens.boundary;

import java.util.List;

import javax.ejb.Stateless;
import javax.inject.Inject;

import pl.devcrowd.virtual.business.chickens.controls.ChickenStore;
import pl.devcrowd.virtual.business.chickens.entity.Chicken;

@Stateless
public class ChickenService {

    @Inject
    ChickenStore cs;

    public List<Chicken> getAllChickens() {
        return this.cs.all();
    }

    public void save(Chicken chicken) {
        this.cs.save(chicken);
    }
}

实体

包包含实体：

package pl.devcrowd.virtual.business.chickens.entity;

import javax.persistence.Entity;
import javax.persistence.GeneratedValue;
import javax.persistence.Id;
import javax.persistence.NamedQuery;
import javax.xml.bind.annotation.XmlAccessType;
import javax.xml.bind.annotation.XmlAccessorType;
import javax.xml.bind.annotation.XmlRootElement;

@XmlAccessorType(XmlAccessType.FIELD)
@XmlRootElement
@Entity
@NamedQuery(name="all", query = "SELECT c FROM Chicken C")
public class Chicken {

    @Id
    @GeneratedValue
    private long id;
    private String name;
    private int age;

    public Chicken() {}

    public Chicken(String name, int age) {
        this.name = name;
        this.age = age;
    }
}

父包包含我实现的Jax RS应用程序类，希望正确：

package pl.devcrowd.virtual.business;

import java.util.Arrays;
import java.util.HashSet;
import java.util.Set;

import javax.ws.rs.ApplicationPath;
import javax.ws.rs.core.Application;

import pl.devcrowd.virtual.business.chickens.boundary.ChickensResource;

/**
 * Configures a JAX-RS endpoint. Delete this class, if you are not exposing
 * JAX-RS resources in your application.
 *
 * @author airhacks.com
 */
@ApplicationPath("resources")
public class JAXRSConfiguration extends Application {
    public Set<Class<?>> getClasses() {
        return new HashSet<Class<?>>(Arrays.asList(ChickensResource.class));
    }
}

我得到了一个错误：

05:59:17,019 ERROR [org.jboss.resteasy.resteasy_jaxrs.i18n] (default task-3) RESTEASY002005: Failed executing GET /chickens: org.jboss.resteasy.core.NoMessageBodyWriterFoundFailure: Could not find MessageBodyWriter for response object of type: java.util.ArrayList of media type: text/html
    at org.jboss.resteasy.core.ServerResponseWriter.writeNomapResponse(ServerResponseWriter.java:66)
    at org.jboss.resteasy.core.SynchronousDispatcher.writeResponse(SynchronousDispatcher.java:473)
    at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:422)
    at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:209)
    at org.jboss.resteasy.plugins.server.servlet.ServletContainerDispatcher.service(ServletContainerDispatcher.java:221)
    at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:56)
    at org.jboss.resteasy.plugins.server.servlet.HttpServletDispatcher.service(HttpServletDispatcher.java:51)
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:790)
    at io.undertow.servlet.handlers.ServletHandler.handleRequest(ServletHandler.java:85)
    at io.undertow.servlet.handlers.security.ServletSecurityRoleHandler.handleRequest(ServletSecurityRoleHandler.java:62)
    at io.undertow.servlet.handlers.ServletDispatchingHandler.handleRequest(ServletDispatchingHandler.java:36)
    at org.wildfly.extension.undertow.security.SecurityContextAssociationHandler.handleRequest(SecurityContextAssociationHandler.java:78)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.servlet.handlers.security.SSLInformationAssociationHandler.handleRequest(SSLInformationAssociationHandler.java:131)
    at io.undertow.servlet.handlers.security.ServletAuthenticationCallHandler.handleRequest(ServletAuthenticationCallHandler.java:57)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.security.handlers.AbstractConfidentialityHandler.handleRequest(AbstractConfidentialityHandler.java:46)
    at io.undertow.servlet.handlers.security.ServletConfidentialityConstraintHandler.handleRequest(ServletConfidentialityConstraintHandler.java:64)
    at io.undertow.security.handlers.AuthenticationMechanismsHandler.handleRequest(AuthenticationMechanismsHandler.java:60)
    at io.undertow.servlet.handlers.security.CachedAuthenticatedSessionHandler.handleRequest(CachedAuthenticatedSessionHandler.java:77)
    at io.undertow.security.handlers.NotificationReceiverHandler.handleRequest(NotificationReceiverHandler.java:50)
    at io.undertow.security.handlers.AbstractSecurityContextAssociationHandler.handleRequest(AbstractSecurityContextAssociationHandler.java:43)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at org.wildfly.extension.undertow.security.jacc.JACCContextIdHandler.handleRequest(JACCContextIdHandler.java:61)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.server.handlers.PredicateHandler.handleRequest(PredicateHandler.java:43)
    at io.undertow.servlet.handlers.ServletInitialHandler.handleFirstRequest(ServletInitialHandler.java:292)
    at io.undertow.servlet.handlers.ServletInitialHandler.access$100(ServletInitialHandler.java:81)
    at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:138)
    at io.undertow.servlet.handlers.ServletInitialHandler$2.call(ServletInitialHandler.java:135)
    at io.undertow.servlet.core.ServletRequestContextThreadSetupAction$1.call(ServletRequestContextThreadSetupAction.java:48)
    at io.undertow.servlet.core.ContextClassLoaderSetupAction$1.call(ContextClassLoaderSetupAction.java:43)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.api.LegacyThreadSetupActionWrapper$1.call(LegacyThreadSetupActionWrapper.java:44)
    at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:272)
    at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81)
    at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:104)
    at io.undertow.server.Connectors.executeRootHandler(Connectors.java:202)
    at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:805)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

---

我做错了什么？

据我所知，客户端调用mediatype text/html。但是objectmapper不知道如何为arraylist编写html。 您希望xml或json采用哪种格式

@Path("chickens")
public class ChickensResource {

    @Inject
    ChickenService cs;

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    public List<Chicken> chickens() {
        return cs.getAllChickens();
    }

    @POST
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)
    public void save(JsonObject chicken) {
        String name = chicken.getString("name");
        int age = chicken.getInt("age");
        cs.save(new Chicken(name, age));
    }
}

邮件标题：

 Accept: application/json

Accept: application/json
Content-Type: application/json

Accept标头说明响应应采用何种格式。 Content-Type头表示请求有效负载的格式

内容类型：

HTML --> text/html
JSON --> application/json
XML --> application/xml

编辑：我认为这篇文章也有同样的问题。我们现在告诉这些方法，它们使用json作为输入数据，并返回json作为输出数据（products）

但是这些数据真的是在请求中设置的吗。你能告诉我你是如何构建这个帖子的吗

要匹配这些方法，请求中需要有这两个标头：

Accept:application/json

说明客户端需要的格式。 这应该与设置输出格式的服务中的

@products

相匹配。

---

内容类型：application/json

这是我认为缺少的一个，它说明了POST负载的格式，并且应该与服务器输入相匹配

@Consumes

我添加了

@Consumes

和

@products

。现在就开始工作，我会得到一个空列表，就像我应该得到的一样！谢谢现在我有一个POST问题：

执行失败：javax.ws.rs.NotSupportedException:RESTEASY003065:无法使用内容类型

。我可以问一个关于POST的新问题，因为这是关于开始工作的问题，但是你知道问题在哪里吗？客户机还是服务器？我理解错误的含义，而不是发生错误的原因或修复错误的方法。

@Path("chickens")
public class ChickensResource {

    @Inject
    ChickenService cs;

    @GET
    @Produces(MediaType.APPLICATION_JSON)
    public List<Chicken> chickens() {
        return cs.getAllChickens();
    }

    @POST
    @Consumes(MediaType.APPLICATION_JSON)
    @Produces(MediaType.APPLICATION_JSON)
    public void save(JsonObject chicken) {
        String name = chicken.getString("name");
        int age = chicken.getInt("age");
        cs.save(new Chicken(name, age));
    }
}

 Accept: application/json

Accept: application/json
Content-Type: application/json

HTML --> text/html
JSON --> application/json
XML --> application/xml