问题

@Controller
@RequestMapping("/game")
public class ViewController {
    @RequestMapping(value = "/statistic", method = RequestMethod.GET, 
                    produces = {MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML})
    public @ResponseBody GamerData[] getStatistic() {
        RestTemplate restTemplate = new RestTemplate();
        try {
            String uri_get_statistic = "http://localhost:8081/statistic/";
            ResponseEntity<GamerData[]> response = restTemplate.getForEntity(uri_get_statistic, GamerData[].class);
            GamerData[] statisticData = response.getBody();
            return statisticData;
        } catch(Exception e) {
            e.printStackTrace();
            return null;
        }
    }
}

After changing to @Controller, I encountered a 404 error. With @RestController, I was able to receive JSON data. (The GamerData class contains two simple fields: an integer and a string, along with their respective setters, getters, and constructor.)

UPDATE:
I added @ResponseBody to my function, but now I'm facing an Internal Server error:
Resolved [org.springframework.http.converter.HttpMessageNotWritableException: No converter for [class [Lgame.mainservice.mvc.GamerData;] with preset Content-Type 'null']

<details>
<summary>英文:</summary>

I&#39;m trying to return JSON/XML from a function of my Controller. First I was using @RestController and it worked good, but now I need to change to @Controller, because I will use also some other functions and pass there some objects for my view.

@Controller
@RequestMapping("/game")
public class ViewController {
@RequestMapping(value = "/statistic", method = RequestMethod.GET,
produces = {MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML})
public GamerData[] getStatistic() {
RestTemplate restTemplate = new RestTemplate();
try {
String uri_get_statistic = "http://localhost:8081/statistic/";
ResponseEntity<GamerData[]> response = restTemplate.getForEntity(uri_get_statistic, GamerData[].class);
GamerData[] statisticData = response.getBody();
return statisticData;
} catch(Exception e) {
e.printStackTrace();
return null;
}
}

}

After I've changed to Controller I get error 404 not found. With RestController I've got json. (GamerData is just a class with 2 simple fields (int and String), setters, getters, consructor).

UPDATE:
I've added ```@ResponseBody``` to my function, but now I have Internal Server error
```Resolved [org.springframework.http.converter.HttpMessageNotWritableException: No converter for [class [Lgame.mainservice.mvc.GamerData;] with preset Content-Type 'null']```

</details>


# 答案1
**得分**: 0

尝试像下面这样添加 @ResponseBody：

```java
public @ResponseBody GamerData[] getStatistic....

public @ResponseBody GamerData[] getStatistic....

答案2

得分: 0

@RequestMapping(value = "/statistic", method = RequestMethod.GET, 
                produces = {MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML})
@ResponseBody
public GamerData[] getStatistic() {}

@RequestMapping(value = "/statistic", method = RequestMethod.GET, 
                produces = {MediaType.APPLICATION_JSON, MediaType.APPLICATION_XML})
@ResponseBody  // add this one
public GamerData[] getStatistic() {}

答案3

得分: 0

感谢大家的回答，我已经在我的函数中添加了@ResponceBody注解，并从@RequestMapping注解中移除了produces部分，我的函数运行得很好：

@RequestMapping(value = "/statistic", method = RequestMethod.GET)
@ResponseBody
public GamerData[] getStatistic() {
    //函数代码
}

@RequestMapping(value = "/statistic", method = RequestMethod.GET)
@ResponseBody
public GamerData[] getStatistic() {
    //function code
}