How To Parse JSON Using Jackson (Weird Scenario)

Question

So I am creating an application that fetches data from the Alpha Vantage API and I am trying to parse this JSON response that can be seen here.

I have set up 3 Data Transfer Objects like such:

Stock.java

public class Stock extends Dto{

    @JsonProperty("Time Series (Daily)")
    private TimeSeries timeSeries;

    public TimeSeries getTimeSeries() {
        return timeSeries;
    }

    public void setTimeSeries(TimeSeries timeSeries) {
        this.timeSeries = timeSeries;
    }
}

TimeSeries.java

public class TimeSeries extends Dto{


    private List<Date> dates;

    public List<Date> getDates() {
        return dates;
    }

    public void setDates(List<Date> dates) {
        this.dates = dates;
    }
}

Date.java

@JsonIgnoreProperties(ignoreUnknown = true)
public class Date extends Dto{

    @JsonProperty("1. open")
    private double open;

    @JsonProperty("2. high")
    private double high;

    @JsonProperty("3. low")
    private double low;

    @JsonProperty("4. close")
    private double close;

    @JsonProperty("5. volume")
    private double volume;

    public double getOpen() {
        return open;
    }

    public void setOpen(double open) {
        this.open = open;
    }

    public double getHigh() {
        return high;
    }

    public void setHigh(double high) {
        this.high = high;
    }

    public double getLow() {
        return low;
    }

    public void setLow(double low) {
        this.low = low;
    }

    public double getClose() {
        return close;
    }

    public void setClose(double close) {
        this.close = close;
    }

    public double getVolume() {
        return volume;
    }

    public void setVolume(double volume) {
        this.volume = volume;
    }
}

The field in Stock.java populates just fine since I explicitly say the name of the key and a value is accordingly parsed. But in the next step I want to store a List<Date> of objects that contain the information I'm going after and this does not work (returns null) because unless I explicitly give a key for an attribute Jackson just does nothing.

So I'm wondering how do I correctly parse this JSON in Java so that I can get an array of the dates and be able to access the properties of each date holding the information that I'm after?

Answer 1 · 2017-11-13T21:31:05Z

November 13, 2017 9:31pm

I think the main issue is that TimeSeries is a JSON object that uses the date as the key for data objects, not a JSON array. You would do best to place them in a Map than a List (or figure out if Jackson supports converting the key-value pairs into a list/array during parsing).

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Benyam Ephrem

Benyam Ephrem

How To Parse JSON Using Jackson (Weird Scenario)

1 Answer

Seth Kroger

Seth Kroger

Benyam Ephrem

Benyam Ephrem