java - 使用 Jersey 从 MongoDb 发送 Json 响应

Question

我有以下代码。我想退回 catalog 中存在的所有文档作为 json 响应。我可以使用 DBCursor 打印所有文档.

@Path("/allmusic")
public class GetAllMusic {

    @Produces(MediaType.APPLICATION_JSON)
    @GET
    public void getAllSongs(@Context HttpHeaders httpHeaders) throws UnknownHostException {

        DB db = (new MongoClient("localhost",27017)).getDB("sampledb");
        DBCollection dbCollection = db.getCollection("catalog");

        DBCursor cursor = dbCollection.find();

        while(cursor.hasNext())
        {
            System.out.println(cursor.next());
        }
    }


}

如何将所有文档作为 json 响应返回？如果我的问题很愚蠢，请原谅，我还是个初学者。

编辑 我对代码进行了以下添加:

GetAllMusic.java

 @Path("/allmusic")
    public class GetAllMusic {
        @GET
        @Produces(MediaType.APPLICATION_JSON)
        @Path("/playlist")
        public Response getAllSongs(@Context HttpHeaders httpHeaders)
         throws UnknownHostException, JsonProcessingException {

                DB db = (new MongoClient("localhost",27017)).getDB("xmusicdb");
                DBCollection dbCollection = db.getCollection("catalog");

                DBCursor cursor = dbCollection.find();

                List<CatalogPojo> result = new ArrayList<>();
                while(cursor.hasNext()) {
                    result.add(new CatalogPojo(cursor.next()));
                }
                String json = new ObjectMapper().writeValueAsString(result);
                return Response.ok(json, MediaType.APPLICATION_JSON).build();
            }

        }

目录Pojo.java

public class CatalogPojo {

    private String title, artist, album, year;


    /*CatalogPojo(String title, String artist, String album, String year){

    }*/

    public CatalogPojo(DBObject next) {

    }

    public String getTitle() {
        return title;
    }

    public void setTitle(String title) {
        this.title = title;
    }

    public String getArtist() {
        return artist;
    }

    public void setArtist(String artist) {
        this.artist = artist;
    }

    public String getAlbum() {
        return album;
    }

    public void setAlbum(String album) {
        this.album = album;
    }

    public String getYear() {
        return year;
    }

    public void setYear(String year) {
        this.year = year;
    }
}

http://localhost:xxxx/xmusic/allmusic/playlist访问此 url 时，我收到 404。我认为我的 pojo 文件或 List<CatalogPojo> 有问题。

Answer 1

你就快到了。试试这个:

@Path("v1")
public class GetAllMusic {
    @GET
    @Path("/allmusic")
    @Produces(MediaType.APPLICATION_JSON)
    public Response getAllSongs {
        ...
        List<AppropriatePojo> result = new ArrayList<>();
        while(cursor.hasNext()) {
            result.add(new AppropriatePojo(cursor.next()));
        }
        String json = new ObjectMapper().writeValueAsString(result);
        return Response.ok(json, MediaType.APPLICATION_JSON).build();
    }

然后使用浏览器或使用 Chorme 插件 PostMan 访问 localhost:xxxx/v1/allmusic。