春假休息服务

Question

I'm working with example from https://spring.io/guides/gs/rest-service/ and I changed default class Greeting to my own class and, when I'm calling this in web browser http://localhost:8080/greeting I get answer: There was an unexpected error (type=Not Acceptable, status=406). Could not find acceptable representation There was an unexpected error (type=Not Acceptable, status=406). Could not find acceptable representation

My controller:

package rest;

import java.util.concurrent.atomic.AtomicLong;

import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;
import org.springframework.web.bind.annotation.RestController;

import database.*;

@RestController
public class GreetingController {

    private static final String template = "Hello, %s!";
    private final AtomicLong counter = new AtomicLong();
    private DBAccess dbaccess= new DBAccess();

    @RequestMapping("/greeting")
    public Customer greeting(@RequestParam(value="name", defaultValue="World") String name) {
        return new  Customer(1,"a","b");
    }
}

And customer class:

package database;

public class Customer {
    private long id;
    private  String firstName, lastName;

    public Customer(){};
    public Customer(long id, String firstName, String lastName) {
        this.id = id;
        this.firstName = firstName;
        this.lastName = lastName;
    }


    void setFirstName(String firstName){
        this.firstName=firstName;
    }

    void setLastName(String lastName){
        this.lastName=lastName;
    }


    @Override
    public String toString() {
        return String.format(
                "Customer[id=%d, firstName='%s', lastName='%s']",
                id, firstName, lastName);
    }
}

following Spring MVC Rest / JSON service I added jackson mapper dependency but it doesn't works...

Please help me

According to nebula comment. I haven't web.xml, I'm using example from https://spring.io/guides/gs/rest-service/ and there isn't any.

Here is my Application.class

package rest;

import org.springframework.boot.autoconfigure.EnableAutoConfiguration;
import org.springframework.boot.SpringApplication;
import org.springframework.context.annotation.ComponentScan;

@ComponentScan
@EnableAutoConfiguration
public class Application {

    public static void main(String[] args) {
        SpringApplication.run(Application.class, args);
    }
}

Answer 1

You probably have a JsonMappingException.

I think you need to add getters/setters or make some attributes public, because Jackson is probably confused when serializing your Customer class.

Answer 2

Try to define method and response type.

@RequestMapping(value = "/greeting", method = RequestMethod.GET, 
produces = "application/json; charset=utf-8")
@ResponseBody
public Customer greeting(@RequestParam(value="name", defaultValue="World") String name) {

Also make sure it is correctly mapped as http://localhost:8080/greeting

Answer 3

You have to use @ResponseBody annotation for your greeting method as following

 @RequestMapping("/greeting") 
 public @ResponseBody Customer greeting(@RequestParam(value="name", defaultValue="World") String name) {
     return new  Customer(1,"a","b"); 
 } 

It is used for object serialization. It will try to convert return value (customer object) and write it to the http response automatically.

Answer 4

I am under the impression the lack of getters for your private fields in your Customer might cause the trouble

Besides, have you added the JSON path dependency in your pom.xml?

 <dependency>
      <groupId>com.jayway.jsonpath</groupId>
      <artifactId>json-path</artifactId>
      <scope>test</scope>
 </dependency>

Answer 5

Are you using Spring Boot? If you are, your Application class should be annotated with @SpringBootApplication . This bundles the @EnableWebMvc , @Configuration , @ComponentScan and @EnableAutoConfiguration annotations. A stacktrace would be helpful to try figure out exactly what the issue is.

Answer 6

change your

 public static void main(String[] args) {
    SpringApplication.run(Application.class, args);
}

To

  public static void main(String[] args) {
        SpringApplication.run(GreetingController.class, args);
    }