春季：返回@ResponseBody“响应实体<列表<JSONObject>>”

json rest java http-status-codes spring

2022-09-01 05:06:45

在控制器中，我创建 json 数组。如果我返回，没关系：List<JSONObject>

@RequestMapping(value="", method=RequestMethod.GET, produces=MediaType.APPLICATION_JSON_VALUE)
public @ResponseBody List<JSONObject> getAll() {
    List<Entity> entityList = entityManager.findAll();

    List<JSONObject> entities = new ArrayList<JSONObject>();
    for (Entity n : entityList) {
        JSONObject entity = new JSONObject();
        entity.put("id", n.getId());
        entity.put("address", n.getAddress());
        entities.add(entity);
    }
    return entities;
}

但我需要返回JSON数组和HTTP状态代码：

@RequestMapping(value="", method=RequestMethod.GET, produces=MediaType.APPLICATION_JSON_VALUE)
public @ResponseBody ResponseEntity<List<JSONObject>> getAll() {
    List<Entity> entityList = entityManager.findAll();

    List<JSONObject> entities = new ArrayList<JSONObject>();
    for (Entity n : entityList) {
        JSONObject Entity = new JSONObject();
        entity.put("id", n.getId());
        entity.put("address", n.getAddress());
        entities.add(entity);
    }
    return new ResponseEntity<JSONObject>(entities, HttpStatus.OK); // XXX
}

Eclipse 在 XXX 行中看到错误：

Multiple markers at this line
    - The constructor ResponseEntity<JSONObject>(List<JSONObject>, HttpStatus) is undefined
    - Type mismatch: cannot convert from ResponseEntity<JSONObject> to 
     ResponseEntity<List<JSONObject>>
    - Type mismatch: cannot convert from ResponseEntity<JSONObject> to JSONObject

如何返回 json+http 回复？我有一个工作代码用于返回一个json对象+ http状态代码：

@RequestMapping(value="/{address}", method=RequestMethod.GET, produces=MediaType.APPLICATION_JSON_VALUE)
public @ResponseBody ResponseEntity<JSONObject> getEntity(@PathVariable("address") int address) {
    Entity n = entityManager.findByAddress(address);
    JSONObject o = new JSONObject();
    o.put("id", n.getId());
    o.put("address", n.getAddress());
    return new ResponseEntity<JSONObject>(o, HttpStatus.OK);
}

答案 1

而不是

return new ResponseEntity<JSONObject>(entities, HttpStatus.OK);

尝试

return new ResponseEntity<List<JSONObject>>(entities, HttpStatus.OK);

答案 2

现在我回来了。我不知道更好的解决方案，但它有效。Object

@RequestMapping(value="", method=RequestMethod.GET, produces=MediaType.APPLICATION_JSON_VALUE)
public @ResponseBody ResponseEntity<Object> getAll() {
    List<Entity> entityList = entityManager.findAll();

    List<JSONObject> entities = new ArrayList<JSONObject>();
    for (Entity n : entityList) {
        JSONObject Entity = new JSONObject();
        entity.put("id", n.getId());
        entity.put("address", n.getAddress());
        entities.add(entity);
    }
    return new ResponseEntity<Object>(entities, HttpStatus.OK);
}