我如何在JSON中使用replace？

Question

嘿，我有一个JSON字符串，即

{"userId":"WaNenOnQt","photos":[{"photo_url":"vendor_photos/WaNenOnQt/web_(138)(4thcopy).JPG","index":1},{"photo_url":"vendor_photos/WaNenOnQt/54230451_265006064447640_7942942433146217157_n.jpg","index":2}]}

我只想要列表数据，即-

[{"photo_url":"vendor_photos/WaNenOnQt/web_(138)(4thcopy).JPG","index":1},{"photo_url":"vendor_photos/WaNenOnQt/54230451_265006064447640_7942942433146217157_n.jpg","index":2}]

java中是否有任何replace函数，或者如何分隔列表？

Answer 1

假设您正在通过公开的端点获取JSON，则应将其绑定到方法签名，例如，如果您使用的是Spring：

public class MyPojo {
    private String userId;
    private List<Photo> photoList;
    //getters & setters
}

Photo class

public class Photo {
    @JsonProperty("photo_url")
    private String url;
    private int index;
    //getters & setters
}

Controller class

@RequestMapping(value = "/test", method = RequestMethod.POST, produces = MediaType.APPLICATION_JSON_VALUE)
public ResponseEntity<Object> test(@RequestBody MyPojo request) {
    List<Photo> photos = request.getPhotoList();
}

或者，如果没有端点，则可以使用Java的ObjectMapper将JSON字符串手动转换为POJO，反之亦然。例如：

public void transform(String jsonString) throws... {
    ObjectMapper mapper = new ObjectMapper();
    MyPojo pojo = mapper.readValue(jsonString, MyPojo.class);
    List<Photo> photo = pojo.getPhotoList();
}

我还假设您需要一个Java列表，并且不需要将JSON数组简单地当作字符串。

Answer 2

您可以使用小型json库

String jsonstring = "{\"userId\":\"WaNenOnQt\",\"photos\":[{\"photo_url\":\"vendor_photos/WaNenOnQt/web_(138)(4thcopy).JPG\",\"index\":1},{\"photo_url\":\"vendor_photos/WaNenOnQt/54230451_265006064447640_7942942433146217157_n.jpg\",\"index\":2}]}";
JsonValue json = JsonParser.parse(jsonstring);
JsonValue photos = json.asObject().first("photos");
String result = photos.toCompactString();