Java readEntity（Object.class）无法从实体流反序列化对象

我必须从数据库中获取用户。我正在使用字符串引导的微服务。代码如下：

@RequestMapping(value = "/obtener/{nombre}", method = RequestMethod.GET, produces = "application/json")
public ResponseEntity<?> ObtenerUsuario(@PathVariable(value = "nombre", required = true) String nombre) {
        
    System.out.println("Acceso al microservicio: http://localhost:11708/obtener");
        
    List<Usuario> usuarios = usuariosDAO.findByNombre(nombre);
        
    if(usuarios.size()>1) {
        System.out.println("ERROR: Varios usuarios tienen el mismo nombre");
        return new ResponseEntity<>(HttpStatus.INTERNAL_SERVER_ERROR);
    }
        
    if(!usuarios.isEmpty()) {
        System.out.print("El nombre de usuario se ha encontrado");
        return new ResponseEntity<>(usuarios.get(0), HttpStatus.FOUND);
    }
        
    System.out.println("El usuario no se ha encontrado");
    return new ResponseEntity<>(HttpStatus.NOT_FOUND);
}

但readEntity（Usuario.class）无法从实体流反序列化对象，它会抛出以下内容：

StandardWrapperValve[controlador.ServletController]: Servlet.service() for servlet controlador.ServletController threw exception
javax.ws.rs.ProcessingException: Error deserializing object from entity stream.
at org.glassfish.jersey.jsonb.internal.JsonBindingProvider.readFrom(JsonBindingProvider.java:101)
at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$TerminalReaderInterceptor.invokeReadFrom(ReaderInterceptorExecutor.java:257)
at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$TerminalReaderInterceptor.aroundReadFrom(ReaderInterceptorExecutor.java:236)
at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor.proceed(ReaderInterceptorExecutor.java:156)
at org.glassfish.jersey.message.internal.MessageBodyFactory.readFrom(MessageBodyFactory.java:1091)
at org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:874)
at org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:808)
at org.glassfish.jersey.client.ClientResponse.readEntity(ClientResponse.java:321)
at org.glassfish.jersey.client.InboundJaxrsResponse$1.call(InboundJaxrsResponse.java:115)
...

---

你知道我错在哪里吗？谢谢。我终于解决了。我的问题是我没有为java对象创建空构造函数。JSON使用这些作为默认值

StandardWrapperValve[controlador.ServletController]: Servlet.service() for servlet controlador.ServletController threw exception
javax.ws.rs.ProcessingException: Error deserializing object from entity stream.
at org.glassfish.jersey.jsonb.internal.JsonBindingProvider.readFrom(JsonBindingProvider.java:101)
at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$TerminalReaderInterceptor.invokeReadFrom(ReaderInterceptorExecutor.java:257)
at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor$TerminalReaderInterceptor.aroundReadFrom(ReaderInterceptorExecutor.java:236)
at org.glassfish.jersey.message.internal.ReaderInterceptorExecutor.proceed(ReaderInterceptorExecutor.java:156)
at org.glassfish.jersey.message.internal.MessageBodyFactory.readFrom(MessageBodyFactory.java:1091)
at org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:874)
at org.glassfish.jersey.message.internal.InboundMessageContext.readEntity(InboundMessageContext.java:808)
at org.glassfish.jersey.client.ClientResponse.readEntity(ClientResponse.java:321)
at org.glassfish.jersey.client.InboundJaxrsResponse$1.call(InboundJaxrsResponse.java:115)
...