没有找到Kotlin MessageBodyWriter的JAX-RS
我已经用Kotlin和（b）用Java实现了JAX-RS资源（a）。 虽然Java的风格按预期工作，但Kotlin味道失败， MessageBodyWriter not found for media type=application/json, type=class java.util.ArrayList, genericType=java.util.List<? extends ....Entry>.|#] MessageBodyWriter not found for media type=application/json, type=class java.util.ArrayList, genericType=java.util.List<? extends ....Entry>.|#]异常。
这是我的资源
@Path("demokotlin") class DemoKotlinResource { @GET @Path("responseGenericEntityWithArrayList") fun arrayList(): Response { val list = arrayListOf(Entry("responseGenericEntityWithArrayList")) val entity = object : GenericEntity<List<Entry>>(list) {} return Response .status(Response.Status.OK) .entity(entity) .type(MediaType.APPLICATION_JSON).build() } } @XmlRootElement @XmlAccessorType(XmlAccessType.FIELD) open class Entry(val fieldName: String)
整合测试本质上是
private val client = ClientBuilder.newClient() private val target = client.target("http://localhost:8080/xyz/resources/demokotlin") @Test fun responseGenericEntityWithArrayList() { val response = target.path("responseGenericEntityWithArrayList").request(MediaType.APPLICATION_JSON).get() assertThat("no ok status", response.status, equalTo(200)) val entity = response.readEntity(JsonArray::class.java) assertThat(entity.getJsonObject(0).getString("fieldName"), equalTo("responseGenericEntityWithArrayList")) assertThat(entity.toString(), equalTo("[{\"fieldName\":\"responseGenericEntityWithArrayList\"}]")) }
在Java中的等效代码工作正常，而在Kotlin中显示的代码抛出MessageBodyWriter not found for media type=application/json, type=class java.util.ArrayList, genericType=java.util.List<? extends ....Entry>.|#] MessageBodyWriter not found for media type=application/json, type=class java.util.ArrayList, genericType=java.util.List<? extends ....Entry>.|#] 。
我正在使用Payara 4.1.2.172。 挖掘一些JAX-RS类，我发现Java代码导致
genericType=java.util.List<....Entry>
（没有? extends ），而Kotlin的泛型类型信息是
genericType=java.util.List<? extends ....Entry>
这可能是原因吗？ 如果是这样，我该如何解决这个问题？
编辑2017-07-25这里是堆栈跟踪
#|2017-07-25T12:33:16.932+0000|INFO|Payara 4.1||_ThreadID=32;_ThreadName=http-thread-pool::http-listener-1(1);_TimeMillis=1500985996932;_LevelValue=800;| javax.ws.rs.InternalServerErrorException: HTTP 500 Internal Server Error at org.glassfish.jersey.server.internal.MappableExceptionWrapperInterceptor.aroundWriteTo(MappableExceptionWrapperInterceptor.java:90) at org.glassfish.jersey.message.internal.WriterInterceptorExecutor.proceed(WriterInterceptorExecutor.java:162) at org.glassfish.jersey.message.internal.MessageBodyFactory.writeTo(MessageBodyFactory.java:1130) at org.glassfish.jersey.server.ServerRuntime$Responder.writeResponse(ServerRuntime.java:711) at org.glassfish.jersey.server.ServerRuntime$Responder.processResponse(ServerRuntime.java:444) at org.glassfish.jersey.server.ServerRuntime$Responder.process(ServerRuntime.java:434) at org.glassfish.jersey.server.ServerRuntime$2.run(ServerRuntime.java:329) at org.glassfish.jersey.internal.Errors$1.call(Errors.java:271) at org.glassfish.jersey.internal.Errors$1.call(Errors.java:267) at org.glassfish.jersey.internal.Errors.process(Errors.java:315) at org.glassfish.jersey.internal.Errors.process(Errors.java:297) at org.glassfish.jersey.internal.Errors.process(Errors.java:267) at org.glassfish.jersey.process.internal.RequestScope.runInScope(RequestScope.java:317) at org.glassfish.jersey.server.ServerRuntime.process(ServerRuntime.java:305) at org.glassfish.jersey.server.ApplicationHandler.handle(ApplicationHandler.java:1154) at org.glassfish.jersey.servlet.WebComponent.serviceImpl(WebComponent.java:473) at org.glassfish.jersey.servlet.WebComponent.service(WebComponent.java:427) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:388) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:341) at org.glassfish.jersey.servlet.ServletContainer.service(ServletContainer.java:228) at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1606) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:338) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.glassfish.tyrus.servlet.TyrusServletFilter.doFilter(TyrusServletFilter.java:305) at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:250) at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:208) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:256) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160) at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:654) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:593) at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:155) at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:371) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:238) at com.sun.enterprise.v3.services.impl.ContainerMapper$HttpHandlerCallable.call(ContainerMapper.java:466) at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:169) at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:206) at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:180) at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:235) at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119) at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:284) at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:201) at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:133) at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:112) at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77) at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:539) at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:112) at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:117) at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:56) at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:137) at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:593) at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:573) at java.lang.Thread.run(Thread.java:748) Caused by: org.glassfish.jersey.message.internal.MessageBodyProviderNotFoundException: MessageBodyWriter not found for media type=application/json, type=class java.util.ArrayList, genericType=java.util.List<? extends com.github.reproducer.boundary.Entry>. at org.glassfish.jersey.message.internal.WriterInterceptorExecutor$TerminalWriterInterceptor.aroundWriteTo(WriterInterceptorExecutor.java:247) at org.glassfish.jersey.message.internal.WriterInterceptorExecutor.proceed(WriterInterceptorExecutor.java:162) at org.glassfish.jersey.server.internal.JsonWithPaddingInterceptor.aroundWriteTo(JsonWithPaddingInterceptor.java:106) at org.glassfish.jersey.message.internal.WriterInterceptorExecutor.proceed(WriterInterceptorExecutor.java:162) at org.glassfish.jersey.server.internal.MappableExceptionWrapperInterceptor.aroundWriteTo(MappableExceptionWrapperInterceptor.java:86) ... 52 more |#]
编辑＃2： 工作 Java代码 – 应该与Kotlin变体非常相似
@Path("demojava") public class DemoJavaResource { @GET @Path("responseGenericEntityWithArrayList") public Response arrayList() { final List<JEntry> list = new ArrayList<>(); list.add(new JEntry("responseGenericEntityWithArrayList")); final GenericEntity<List<JEntry>> entity = new GenericEntity<List<JEntry>>(list) {}; return Response .status(Response.Status.OK) .entity(entity) .type(MediaType.APPLICATION_JSON).build(); } }
和JEntry
@XmlRootElement @XmlAccessorType(XmlAccessType.FIELD) class JEntry { private String fieldName; JEntry() { this(""); } JEntry(final String responseGenericEntityWithArrayList) { fieldName = responseGenericEntityWithArrayList; } public String getFieldName() { return fieldName; } }
因为JAX-RS不能将ArrayList编码为JSON数组。
MessageBodyWriter是将Java数据类型转换为输出格式的处理程序， 例如 XML，JSON。 JAX-RS内置主要数据类型（包括JAXB）的MessageBodyWriter ，但是那些不包含ArrayList 。 因此，您需要创建一个自定义MessageBodyWriter来接受ArrayList并将其编码为JSON。
但在这种情况下，任何自定义的MessageBodyWriter是不需要的。 而不是，你需要重新创建Entry类。 对不起，我不能写Kotlin样本，但是如果使用Java写的话，
@Path("demokotlin") public class DemoKotlinResource { @GET @Path("responseGenericEntityWithArrayList") public Response arrayList() { Entry entity = new Entry(); entity.fieldName.add("responseGenericEntityWithArrayList"); return Response .status(Response.Status.OK) .entity(entity) .type(MediaType.APPLICATION_JSON).build(); } } @XmlRootElement @XmlAccessorType(XmlAccessType.FIELD) public class Entry { public List<String> fieldName = new ArrayList<>(); }
它转化为Kotlin，然后它可能完成。