RestEasy ExceptionMapper不允许异常序列化错误MediaType八位字节流
我在这里展示了简单的rest服务来说明我收到的异常 服务ARestEasy ExceptionMapper不允许异常序列化错误MediaType八位字节流,rest,resteasy,java-ee-7,wildfly-10,Rest,Resteasy,Java Ee 7,Wildfly 10,我在这里展示了简单的rest服务来说明我收到的异常 服务A @Path("/A") public class ServiceA { @GET @Produces({ MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON}) public Response show() { return Response.ok(new User("John", "Doe")).build(); } } 型号:
@Path("/A")
public class ServiceA {
@GET
@Produces({ MediaType.APPLICATION_XML, MediaType.APPLICATION_JSON})
public Response show() {
return Response.ok(new User("John", "Doe")).build();
}
}
型号:
用户
@XmlRootElement
public class User {
private String firstName;
private String lastName;
public User() {
}
public User(String firstName, String lastName) {
this.firstName = firstName;
this.lastName = lastName;
}
public String getFirstName() {
return firstName;
}
public void setFirstName(String firstName) {
this.firstName = firstName;
}
public String getLastName() {
return lastName;
}
public void setLastName(String lastName) {
this.lastName = lastName;
}
}
错误响应
@XmlRootElement
public class ErrorResponse {
private String errorType;
private String errorMessage;
public ErrorResponse() {
}
public ErrorResponse(String errorType, String errorMessage) {
this.errorType = errorType;
this.errorMessage = errorMessage;
}
public String getErrorType() {
return errorType;
}
public void setErrorType(String errorType) {
this.errorType = errorType;
}
public String getErrorMessage() {
return errorMessage;
}
public void setErrorMessage(String errorMessage) {
this.errorMessage = errorMessage;
}
}
最后,我的例外外观如下所示:
@Provider
public class GenericExceptionMapper implements ExceptionMapper<Exception> {
private final Logger LOG = LoggerFactory.getLogger(GenericExceptionMapper.class);
@Override
public Response toResponse(Exception exception) {
ErrorResponse errorResponse = new ErrorResponse(exception.getClass().getSimpleName(), exception.getMessage());
if (exception instanceof WebApplicationException) {
LOG.error("Type: {}", exception.getClass().getSimpleName());
LOG.error("Message: {}", exception.getMessage());
WebApplicationException webApplicationException = (WebApplicationException) exception;
return Response.status(webApplicationException.getResponse().getStatus()).entity(errorResponse).build();
}
return Response.serverError().entity(errorResponse).build();
}
}
但是,在此URI上调用POST时,我遇到一个异常:
2017-01-13 16:53:46,859 ERROR [com.aizaz.samples.exceptionmapper.GenericExceptionMapper] (default task-35) Type: NotAllowedException
2017-01-13 16:53:46,860 ERROR [com.aizaz.samples.exceptionmapper.GenericExceptionMapper] (default task-35) Message: RESTEASY003650: No resource method found for POST, return 405 with Allow header
2017-01-13 16:53:46,860 ERROR [io.undertow.request] (default task-35) UT005023: Exception handling request to /exception-mapper-example/rest/A: org.jboss.resteasy.spi.UnhandledException: org.jboss.resteasy.core.NoMessageBodyWriterFoundFailure: Could not find MessageBodyWriter for response object of type: com.aizaz.samples.model.ErrorResponse of media type: application/octet-stream
at org.jboss.resteasy.core.SynchronousDispatcher.writeException(SynchronousDispatcher.java:180)
at org.jboss.resteasy.core.SynchronousDispatcher.invoke(SynchronousDispatcher.java:199)
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:284)
at io.undertow.servlet.handlers.ServletInitialHandler.dispatchRequest(ServletInitialHandler.java:263)
at io.undertow.servlet.handlers.ServletInitialHandler.access$000(ServletInitialHandler.java:81)
at io.undertow.servlet.handlers.ServletInitialHandler$1.handleRequest(ServletInitialHandler.java:174)
at io.undertow.server.Connectors.executeRootHandler(Connectors.java:202)
at io.undertow.server.HttpServerExchange$1.run(HttpServerExchange.java:793)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at java.lang.Thread.run(Thread.java:745)
Caused by: org.jboss.resteasy.core.NoMessageBodyWriterFoundFailure: Could not find MessageBodyWriter for response object of type: com.aizaz.samples.model.ErrorResponse of media type: application/octet-stream
at org.jboss.resteasy.core.ServerResponseWriter.writeNomapResponse(ServerResponseWriter.java:66)
at org.jboss.resteasy.core.SynchronousDispatcher.writeException(SynchronousDispatcher.java:176)
... 32 more
相关部分
Caused by: org.jboss.resteasy.core.NoMessageBodyWriterFoundFailure:
Could not find MessageBodyWriter for response object of type:
com.aizaz.samples.model.ErrorResponse of media type: application/octet-stream
显然,序列化失败,因为媒体类型为:application/octet stream
我知道我可以在构建响应时显式指定媒体类型,例如
Response.ok().type(MediaType.APPLICATION_JSON).build();
但我不想那样做;因为我接受JSON/XMLAccept头,并希望以JSON或XML格式返回适当的响应
如果有人能向我提供他/她的宝贵智慧,那就太好了。您可以使用JAX-RS API的
HttpHeaders
管理ExceptionMapper
返回的适当格式,并获取请求实体的MediaType
,参见javadoc:
因此,您的代码如下所示:
@Provider
public class GenericExceptionMapper implements ExceptionMapper<Exception> {
@Context
private HttpHeaders m_headers;
private final Logger LOG = LoggerFactory.getLogger(GenericExceptionMapper.class);
@Override
public Response toResponse(Exception exception) {
ErrorResponse errorResponse = new ErrorResponse(exception.getClass().getSimpleName(), exception.getMessage());
if (exception instanceof WebApplicationException) {
LOG.error("Type: {}", exception.getClass().getSimpleName());
LOG.error("Message: {}", exception.getMessage());
WebApplicationException webApplicationException = (WebApplicationException) exception;
return Response.status(webApplicationException.getResponse().getStatus()).entity(errorResponse).build();
}
return Response.serverError().entity(errorResponse).type(m_headers.getMediaType()).build();
}
}
@Provider
公共类GenericeExceptionMapper实现ExceptionMapper{
@上下文
私有HttpHeader m_头;
私有最终记录器LOG=LoggerFactory.getLogger(genericeExceptionMapper.class);
@凌驾
公众响应(例外){
ErrorResponse ErrorResponse=新的ErrorResponse(exception.getClass().getSimpleName(),exception.getMessage());
if(WebApplicationException的异常实例){
LOG.error(“Type:{}”,exception.getClass().getSimpleName());
错误(“消息:{}”,exception.getMessage());
WebApplicationException WebApplicationException=(WebApplicationException)异常;
返回Response.status(webApplicationException.getResponse().getStatus()).entity(errorResponse.build();
}
返回Response.serverError().entity(errorResponse.type(m_headers.getMediaType()).build();
}
}
如果自定义异常扩展了WebApplicationException
,例如
public class MyCustomException extends WebApplicationException
不需要显式的异常处理和响应创建
ExceptionApper可以非常有助于处理从Exception
(或其子类)而不是WebApplicationException
(及其子类)派生的异常(注意WebApplicationException
也是Exception
的子类)
例如,ExceptionMapper可用于处理异常,如IllegalArgumentException
和创建响应
在上述两种情况下,可以根据Resource方法上指定的@products
序列化响应
然而,在查看RestEasy的规范实现后,我发现,即使对于WebApplicationException
(s),如果rest服务提供了一个异常apper,它也会被触发
resteasy-jaxrs:3.1.0.Final
class: ExceptionHandler
method: public Response handleException(HttpRequest request, Throwable e)
// First try and handle it with a mapper
if ((jaxrsResponse = executeExceptionMapper(e)) != null) {
return jaxrsResponse;
}
因此,我要么确保ExceptionMapper用于某些特定的异常,例如ExceptionMapper
,而不是捕获代码ExceptionMapper
中如上所示的所有异常,要么返回如下代码所示的响应:
if (exception instanceof WebApplicationException) {
WebApplicationException webApplicationException = (WebApplicationException) exception;
return webApplicationException.getResponse();
}
序列化错误将不会发生。为什么?由于框架负责这一点(基于@生成的注释,它将序列化非基于WebApplicationException的响应。对于如上所示基于WebApplicationException
的响应,框架也将负责响应(因为从未使用ErrorResponse实体)
但是,出现了此票证中提到的问题。NotAllowedException
在执行与URI关联的方法之前,在规范实现代码中发生。因此,@生成的注释不会生效,并且在封送响应时,使用默认的MediaType八位字节流
resteasy-jaxrs:3.1.0.Final
class: SegmentNode
method: public Match match(List<Match> matches, String httpMethod, HttpRequest request)
当服务器尝试写入响应时,它找不到MediaType(因为我们在创建响应对象时从未设置它)
它试图从方法注释中设置它;正如前面提到的,方法注释从未设置过,因为NotAllowedException
发生在RESTEASY\u selected\u ACCEPT
可以设置之前
它发现了一个通配符,因为没有指定接受头,所以设置了八位字节流
resteasy-jaxrs:3.1.0.Final
class: ServerResponseWriter
method: protected static void setDefaultContentType(HttpRequest request, BuiltResponse ...
if (chosen.isWildcardType()) {
chosen = MediaType.APPLICATION_OCTET_STREAM_TYPE;
}
(这只是一个总结;对于详细的步骤,我必须回到规范实现代码)
因此,我必须指定一个mediatype。这可以通过查看@Context
中的HttpHeaders
来实现,以使其成为动态的,或者如果在头中没有指定任何内容(如我的情况),我将提供一个默认的mediatype应用程序/XML
,以便继续序列化
希望这也能帮助面临同样问题的人。感谢您的回复。我碰巧调试了RestEasy规范的实现以了解问题。您的解决方案只有在请求头中设置了ContentType时才有效。这意味着,我需要显式指定始终指定内容类型的客户端。请注意,如果出现异常从资源中抛出;在构造响应对象时不需要指定mediatype。原因是如果请求中未指定内容类型,则注释“生成”足够找到MessageBodyWriter进行封送处理;但是NotAllowedException是特殊的。在这种情况下,您可以通过m_头获取可接受的媒体类型。getAcceptableMediaTypes()。查看此线程:
request.setAttribute(RESTEASY_CHOSEN_ACCEPT, sortEntry.getAcceptType());
return sortEntry.match;
resteasy-jaxrs:3.1.0.Final
class: ServerResponseWriter
method: public static void writeNomapResponse(BuiltResponse jaxrsResponse, final HttpRequest request, ...
if (jaxrsResponse.getEntity() != null && jaxrsResponse.getMediaType() == null) {
setDefaultContentType(request, jaxrsResponse, providerFactory, method);
}
resteasy-jaxrs:3.1.0.Final
class: ServerResponseWriter
method: protected static void setDefaultContentType(HttpRequest request, BuiltResponse ...
if (chosen.isWildcardType()) {
chosen = MediaType.APPLICATION_OCTET_STREAM_TYPE;
}