spring – 消耗HATEOAS资源
作者：互联网
我有一个用Spring构建的简单HATEOAS提供程序,它为我提供了以下资源：
{
"_links" : {
"self" : {
"href" : "http://localhost:8080/employees{?page,size,sort}",
"templated" : true
},
"search" : {
"href" : "http://localhost:8080/employees/search"
}
},
"_embedded" : {
"employees" : [ {
"id" : "5400d5152f5243f1988c649b",
"name" : "Some Employee",
"location" : [ 0.0, 0.0 ],
"_links" : {
"self" : {
"href" : "http://localhost:8080/employees/5400d5152f5243f1988c649b"
}
}
}, {
"id" : "5400d5162f5243f1988c649c",
"name" : "Some Employee",
"location" : [ 0.0, 0.0 ],
"_links" : {
"self" : {
"href" : "http://localhost:8080/employees/5400d5162f5243f1988c649c"
}
}
}, {
"id" : "5400d5172f5243f1988c649d",
"name" : "Some Employee",
"location" : [ 0.0, 0.0 ],
"_links" : {
"self" : {
"href" : "http://localhost:8080/employees/5400d5172f5243f1988c649d"
}
}
} ]
},
"page" : {
"size" : 20,
"totalElements" : 3,
"totalPages" : 1,
"number" : 0
}
}
在一个单独的Spring客户端中,我尝试使用此资源但无济于事：
@RequestMapping("/employees")
public String getAllEmployees() {
try {
ResponseEntity<Resource> responseEntity = restTemplate.getForEntity(RESOURCE_URI, Resource.class);
}
catch(Exception e) {
e.printStackTrace();
}
return null;
}
杰克逊2.0继续抱怨：
org.springframework.http.converter.HttpMessageNotReadableException: Could not read JSON: Unrecognized field "page" (class org.springframework.hateoas.Resource), not marked as ignorable (2 known properties: "content", "links"])
at [Source: org.apache.http.conn.EofSensorInputStream@743a4ace; line: 19, column: 13] (through reference chain: org.springframework.hateoas.Resource["page"]); nested exception is com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "page" (class org.springframework.hateoas.Resource), not marked as ignorable (2 known properties: "content", "links"])
at [Source: org.apache.http.conn.EofSensorInputStream@743a4ace; line: 19, column: 13] (through reference chain: org.springframework.hateoas.Resource["page"])
at org.springframework.http.converter.json.MappingJackson2HttpMessageConverter.readJavaType(MappingJackson2HttpMessageConverter.java:216)
at org.springframework.http.converter.json.MappingJackson2HttpMessageConverter.read(MappingJackson2HttpMessageConverter.java:208)
at org.springframework.web.client.HttpMessageConverterExtractor.extractData(HttpMessageConverterExtractor.java:95)
at org.springframework.web.client.RestTemplate$ResponseEntityResponseExtractor.extractData(RestTemplate.java:784)
at org.springframework.web.client.RestTemplate$ResponseEntityResponseExtractor.extractData(RestTemplate.java:769)
at org.springframework.web.client.RestTemplate.doExecute(RestTemplate.java:549)
at org.springframework.web.client.RestTemplate.execute(RestTemplate.java:502)
at org.springframework.web.client.RestTemplate.getForEntity(RestTemplate.java:264)
at com.provider.spring.controller.EmployeeController.getAllEmployees(EmployeeController.java:34)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:483)
at org.springframework.web.bind.annotation.support.HandlerMethodInvoker.invokeHandlerMethod(HandlerMethodInvoker.java:175)
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.invokeHandlerMethod(AnnotationMethodHandlerAdapter.java:446)
at org.springframework.web.servlet.mvc.annotation.AnnotationMethodHandlerAdapter.handle(AnnotationMethodHandlerAdapter.java:434)
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:945)
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:876)
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:961)
at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:852)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:618)
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:837)
at javax.servlet.http.HttpServlet.service(HttpServlet.java:725)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:291)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:239)
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:219)
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:106)
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:504)
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:142)
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)
at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:610)
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:88)
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:534)
at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:1081)
at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:658)
at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:222)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1566)
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1523)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
at java.lang.Thread.run(Thread.java:745)
Caused by: com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "page" (class org.springframework.hateoas.Resource), not marked as ignorable (2 known properties: "content", "links"])
at [Source: org.apache.http.conn.EofSensorInputStream@743a4ace; line: 19, column: 13] (through reference chain: org.springframework.hateoas.Resource["page"])
at com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException.from(UnrecognizedPropertyException.java:51)
at com.fasterxml.jackson.databind.DeserializationContext.reportUnknownProperty(DeserializationContext.java:731)
at com.fasterxml.jackson.databind.deser.std.StdDeserializer.handleUnknownProperty(StdDeserializer.java:915)
at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.handleUnknownProperty(BeanDeserializerBase.java:1298)
at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.handleUnknownVanilla(BeanDeserializerBase.java:1276)
at com.fasterxml.jackson.databind.deser.BeanDeserializer.vanillaDeserialize(BeanDeserializer.java:243)
at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:118)
at com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:3051)
at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:2206)
at org.springframework.http.converter.json.MappingJackson2HttpMessageConverter.readJavaType(MappingJackson2HttpMessageConverter.java:213)
... 44 more
Sep 05, 2014 3:54:08 PM org.apache.catalina.core.ApplicationDispatcher invoke
WARNING: Servlet jsp is currently unavailable
为了更好,这是我的Resource对象：
https://gist.github.com/Xerosigma/02041fdc0849a651dcbf
我错过了什么？
解决方法:
看起来您的类Resource没有名为page的字段,因此解析器无法处理此json对象：
"page" : {
"size" : 20,
"totalElements" : 3,
"totalPages" : 1,
"number" : 0
}
您可以尝试：
public class Page {
private int size;
private int totalElements;
private int totalPages;
private int number;
// Getters and Setters...
}
在你的课堂资源：
public class Resource<T> extends ResourceSupport {
private final T content;
private Page page;
...
}
标签：spring-mvc,spring,jackson,hateoas,spring-hateoas 来源： https://codeday.me/bug/20190628/1320416.html