如何修复在其主体中返回 null 的响应实体对象

Question

如何修复在正文中返回 null 的休息模板对象

ResponseEntity<List<Spot>> reEntity = new ResponseEntity<List<Spot>>(HttpStatus.OK);
        ParameterizedTypeReference<List<Spot>> parameterizedTypeReference =  new ParameterizedTypeReference<List<Spot>>() {
        };
List<Spot> spots = new ArrayList<Spot>(); //initialized
resEntity.getBody().addAll(spots);//getBody() is  returning null

Answer 1

你应该在这一行定义正文

ResponseEntity<List<Spot>> reEntity = new ResponseEntity<List<Spot>>(HttpStatus.OK);

喜欢下一行

ResponseEntity<List<Spot>> reEntity = new ResponseEntity<List<Spot>>(spots, HttpStatus.OK);

我什至建议您使用 ResponseEntity 构建器，如下所示

ResponseEntity.ok(spots);