Как вывести данные из array которые уже находятся в array в json файле? (Java)

345

24 июня 2018, 01:20

Пишу парсер json на Java с использованием библиотеки json-Simple. Нужно вытащить данные из URL. Получаю такой json с URL (здесь лишь начало, сам файл очень длинный):

null {
"pagelen": 10,
"values": [{
    "description": "Quads/hexes need ordering too; see\r\nhttps://bitbucket.org/fenics-project/dolfin/issues/997/. We are not able\r\nto ensure ordering by simple local operation. Hence we at least check if\r\ncell is ordered (like the one from unit square/cube mesh) otherwise\r\nraise.",
    "links": {
        "decline": {
            "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/pullrequests/476/decline"
        },
        "commits": {
            "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/pullrequests/476/commits"
        },
        "self": {
            "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/pullrequests/476"
        },
        "comments": {
            "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/pullrequests/476/comments"
        },
        "merge": {
            "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/pullrequests/476/merge"
        },
        "html": {
            "href": "https://bitbucket.org/fenics-project/dolfin/pull-requests/476"
        },
        "activity": {
            "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/pullrequests/476/activity"
        },
        "diff": {
            "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/pullrequests/476/diff"
        },
        "approve": {
            "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/pullrequests/476/approve"
        },
        "statuses": {
            "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/pullrequests/476/statuses"
        }
    },
    "title": "Mock ordering check for quads/hexes",
    "close_source_branch": false,
    "merge_commit": null,
    "destination": {
        "commit": {
            "hash": "bd2529300256",
            "links": {
                "self": {
                    "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/commit/bd2529300256"
                }
            }
        },
        "repository": {
            "links": {
                "self": {
                    "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin"
                },
                "html": {
                    "href": "https://bitbucket.org/fenics-project/dolfin"
                },
                "avatar": {
                    "href": "https://bitbucket.org/fenics-project/dolfin/avatar/32/"
                }
            },
            "type": "repository",
            "name": "DOLFIN",
            "full_name": "fenics-project/dolfin",
            "uuid": "{40187f2d-daf4-48d4-9479-3239aba29831}"
        },
        "branch": {
            "name": "master"
        }
    },
    "state": "OPEN",
    "closed_by": null,
    "summary": {
        "raw": "Quads/hexes need ordering too; see\r\nhttps://bitbucket.org/fenics-project/dolfin/issues/997/. We are not able\r\nto ensure ordering by simple local operation. Hence we at least check if\r\ncell is ordered (like the one from unit square/cube mesh) otherwise\r\nraise.",
        "markup": "markdown",
        "html": "<p>Quads/hexes need ordering too; see\n<a href=\"https://bitbucket.org/fenics-project/dolfin/issues/997/\" rel=\"nofollow\">https://bitbucket.org/fenics-project/dolfin/issues/997/</a>. We are not able\nto ensure ordering by simple local operation. Hence we at least check if\ncell is ordered (like the one from unit square/cube mesh) otherwise\nraise.</p>",
        "type": "rendered"
    },
    "source": {
        "commit": {
            "hash": "e6db78d11122",
            "links": {
                "self": {
                    "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/commit/e6db78d11122"
                }
            }
        },
        "repository": {
            "links": {
                "self": {
                    "href": "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin"
                },
                "html": {
                    "href": "https://bitbucket.org/fenics-project/dolfin"
                },
                "avatar": {
                    "href": "https://bitbucket.org/fenics-project/dolfin/avatar/32/"
                }
            },
            "type": "repository",
            "name": "DOLFIN",
            "full_name": "fenics-project/dolfin",
            "uuid": "{40187f2d-daf4-48d4-9479-3239aba29831}"
        },
        "branch": {
            "name": "jan/fix-issue-997"
        }
    },
    "comment_count": 1,
    "author": {
        "username": "blechta",
        "display_name": "Jan Blechta",
        "type": "user",
        "uuid": "{fd86b991-5682-4e96-9036-11095a65840f}",
        "links": {
            "self": {
                "href": "https://api.bitbucket.org/2.0/users/blechta"
            },
            "html": {
                "href": "https://bitbucket.org/blechta/"
            },
            "avatar": {
                "href": "https://bitbucket.org/account/blechta/avatar/32/"
            }
        }
    },
    "created_on": "2018-05-27T22:41:56.033863+00:00",
    "reason": "",
    "updated_on": "2018-05-29T15:58:27.284462+00:00",
    "type": "pullrequest",
    "id": 476,
    "task_count": 0
}, {

Видно что в файле есть массив "values". В этом массиве есть данные, например "description" или "id". Это понятно. Мне их получилось вытащить. Но дальше мы видим, что там еще есть, в массиве "values", другие массивы. Здесь меня интересует массив "author" (в самом конце). Я пытался вывести данные из этого массива, а в частности "username". Но не получается. Вот код, который я пытаюсь привести в работающий вид:

String urlName;
    urlName = "https://api.bitbucket.org/2.0/repositories/fenics-project/dolfin/pullrequests";
    URL url = new URL(urlName);
    try {
        BufferedReader bufferedReaderMain = new BufferedReader(new InputStreamReader(url.openStream()));
        BufferedReader bufferedReaderValuesArray = new BufferedReader(new InputStreamReader(url.openStream()));
        String jsonDataAsStringMain = "";
        String jsonDataAsStringValuesArray = "";
        JSONParser parserForJsonMain = new JSONParser();
        JSONParser parserForJsonValuesArray = new JSONParser();
        while (null != (jsonDataAsStringMain = bufferedReaderMain.readLine())) {
            //System.out.println(str);
            JSONObject jsonObjectMain = (JSONObject)parserForJsonMain.parse(jsonDataAsStringMain);
            JSONArray jsonArrayMain = (JSONArray)jsonObjectMain.get("values");
            for (Object obj : jsonArrayMain) {
                JSONObject valuesOfMainArray = (JSONObject) obj;
                Long id = (Long) valuesOfMainArray.get("id");
                System.out.println("PR ID : " + id);
                String title = (String) valuesOfMainArray.get("title");
                System.out.println("Title : " + title);
                while (null!=(jsonDataAsStringValuesArray=bufferedReaderValuesArray.readLine())){
                    //System.out.println(jsonDataAsStringValuesArray);
                    JSONObject jsonObjectValues = (JSONObject)parserForJsonValuesArray.parse(jsonDataAsStringValuesArray);
                    JSONArray jsonArrayValues = (JSONArray)jsonObjectValues.get("author");
                    for (Object t : jsonArrayValues) {
                        JSONObject valuesOfValuesArray = (JSONObject) t;
                        String username = (String) valuesOfValuesArray.get("username");
                        System.out.println("Username : " + username);
                    }
                }
            }
        }

    } catch (IOException e) {
        e.printStackTrace();
    }

При компилировании получаю:

PR ID : 476
Title : Mock ordering check for quads/hexes
Exception in thread "main" java.lang.NullPointerException at connection.ConnectionToHTTP.main(ConnectionToHTTP.java:46)

То есть выводится корректно "id" и "title". но выдает ошибку на строке: