如何使用URL从Java文件中解析多个JSON对象

Question

我在一个文本文件中有多个JSON对象，并且试图从每个对象中获取数据以获取一些数据并将其存储在数据库中。 以下是我拥有的数据的示例：

{"address":"4565 S Wayside Dr","categories":["Other Textile Goods","Textile Manufacturers"],"city":"Houston","country":"US","dateAdded":"2016-11-17T22:36:43Z","dateUpdated":"2017-09-12T14:29:52Z","keys":["us/tx/houston/4565swaysidedr/-1836686262"],"latitude":"29.6981","longitude":"-95.3212","name":"Radium Textiles LLC","phones":["7136901081"],"postalCode":"77087","province":"TX","sourceURLs":["http://www.citysearch.com/profile/607780624/houston_tx/radium_textiles_llc.html"],"id":"AVwdH8-KkufWRAb52ixf"}
{"address":"6104 Donoho St","categories":["Wholesale Textile Brokers","Textile Brokers"],"city":"Houston","country":"US","dateAdded":"2017-03-26T19:08:42Z","dateUpdated":"2017-03-26T19:08:42Z","imageURLs":["http://images1.citysearch.net/assets/guide/images/logo_citysearch_130x25.gif"],"keys":["us/tx/houston/6104donohost/-214331342"],"latitude":"29.677891","longitude":"-95.324173","name":"T A Textiles","phones":["7136452800"],"postalCode":"77033","province":"TX","sourceURLs":["http://www.superpages.com/bp/houston-tx/t-a-textiles-L2170967950.htm","http://houston.citysearch.com/profile/647921770/houston_tx/t_a_textiles.html"],"id":"AVwdbMI6IN2L1WUfvriy"}
{"address":"4544 S Pinemont Dr","categories":["Other Fabricated Textile Product Manufacturers","Textile Manufacturers","Other Textile Goods"],"city":"Houston","country":"US","dateAdded":"2016-11-17T22:33:12Z","dateUpdated":"2017-09-12T14:29:50Z","keys":["us/tx/houston/4544spinemontdr/-1836686262"],"latitude":"29.8369","longitude":"-95.5160","name":"Radium Textiles LLC","neighborhoods":["Fairbanks/ Northwest Crossing , Northwest Houston"],"phones":["7136901390"],"postalCode":"77041","province":"TX","sourceURLs":["http://www.citysearch.com/profile/694636660/houston_tx/radium_textiles_llc.html","http://www.yellowpages.com/houston-tx/mip/radium-textiles-456243882?lid=456243882"],"websites":["http://api.citygridmedia.com/content/places/v2/click?q=9YKflVKbY9NauPJdMy0B1gS1IhB4xv4EWw0zDoT-UWc_izWF3zs5PKGdfOHubWrvM0QwDCYwbOH2fdLi0dK5xArULcksCCbfR-WWAz9xD1AmGVAQZIom4U3n5R4DuRC8WJCtvJcNItEKoCSfzwapuGnmwGnHDpEGYXGjnN4u8zXqkiimSHFf4_dbqGRbVgNJczcRYGsO7BQjsEDjdlUTJ3CxVQB3K1438yd7WPe-AAAIJEq588kBWNDLbak0Vs-EUxvQmWKBKxWI5ahci9eDn5KNvXpHpqZUL_e0UVacwelpEs92aC0Q2f_N0ZyiviGOHw8dOG3WIXM3rnMIStdm3v06ddF7lICNJl77Z6Y_mtMiylGr2EYGE_lU-dhl6pZnJ92MqQhlZpOjEubWZv1Bd95b8A-INOGKto848V3VdJNGPJwFN_DkdeWGF8YMvDWgew1xs3RSeBeHcBqFzLqQkDbgIllvuxl9VON3HBMwPYjMZ0kqzhi02JRzW0rO_gItNZKuHfHb3rNrWctuJQ2Qvup-kEiLHf5Hya_5KCAgn6uOStAioAXszLKlglJqFMNQE39j6ieFhMg&placement=listing_profile&cs_user=unknown&cs_session=88473fea2af4b100b0e7993b2eafa4bedbe4234c"],"id":"AVwczWsPkufWRAb5zLcG"}
{"address":"7085 Alameda Ave","categories":["Other Textile Goods","Textile Manufacturers","Textile Finishers","Wholesale Textiles"],"city":"El Paso","country":"US","dateAdded":"2017-06-27T05:29:45Z","dateUpdated":"2017-09-06T17:24:47Z","keys":["us/tx/elpaso/7085alamedaave/-266489986"],"latitude":"31.7550","longitude":"-106.3926","name":"Midwest Textile Co","phones":["9158811790"],"postalCode":"79915","province":"TX","sourceURLs":["http://www.citysearch.com/profile/620236204/el_paso_tx/midwest_textile_co.html"],"id":"AVzoBujQLD2H7whiXdiR"}

我试图将其解析如下：

InputStream resourceInputStream =  context.getResourceAsStream("/WEB-INF/jsp/modules/data/20180427-businesses.txt");
            String jsonString = IOUtils.toString(resourceInputStream, "UTF-8");
            JSONObject json = (JSONObject) JSONSerializer.toJSON( jsonString );    
            String address = json.getString("address");

但是由于数据不是单个JSON字符串，因此无法正常工作。 而且，我拥有的数据不在数组内，这使我的工作更加困难。 我还尝试创建一个具有类似变量的Java类，并尝试将JSON字符串直接映射到该类，并且它对我也不起作用。

InputStream resourceInputStream =  context.getResourceAsStream("/WEB-INF/jsp/modules/data/20180427-businesses.txt");
            String jsonString = IOUtils.toString(resourceInputStream, "UTF-8");
            ObjectMapper mapper = new ObjectMapper();
            BusinessDataImportHB records = mapper.readValue(jsonString, BusinessDataImportHB.class);

哪里：

public class BusinessDataImportHB 
{

    private List<BusinessRecord> records;

    public List<BusinessRecord> getRecords() {
        return records;
    }

    public void setRecords(List<BusinessRecord> records) {
        this.records = records;
    }
}

和

public class BusinessRecord {

    private String  address;
    private List<String> categories;
    private String  city;
    private String  country;
    private Date dateAdded;
    private Date dateUpdated;
    private List<String> keys;
    private String latitude;
    private String longitude;
    private String  name;
    private List<String> phones;
    private String postalCode;
    private String province;
    private List<String> websites;
    private String id;

我无法更改数据格式。 我可以用来解析数据并获得单个记录的最佳方法是什么？

Answer 1

如果每个JSON对象都在一行中，则可以逐行读取文件。

try (Stream<String> stream = Files.lines(Paths.get("..."))) {
    stream.forEach(line -> {
        JSONObject json = (JSONObject) JSONSerializer.toJSON(line);    
        String address = json.getString("address");
    });
}

Answer 2

如果您的记录是逐行的，并且文件很大，则可能需要考虑逐行读取和解析。 您可以使用try-with-resources块来确保不会因未关闭的资源而导致内存泄漏。

String pathname = "/home/william/test.txt"; // your file
try (Scanner sc = new Scanner(new FileInputStream(new File(pathname)))) {
    while (sc.hasNextLine()) {
        JSONObject json = (JSONObject) JSONSerializer.toJSON(sc.nextLine());
        // TODO do something with it
    }
} catch (Exception e) {
    // TODO
}