Typed JSON with Jackson example

Test.java

package com.caffinc.learning.json;

import com.fasterxml.jackson.annotation.JsonSubTypes;
import com.fasterxml.jackson.annotation.JsonTypeInfo;
import com.fasterxml.jackson.databind.ObjectMapper;

import java.util.ArrayList;
import java.util.List;

public class Test {
    static class ScheduleList {
        public List<Schedule> schedules;
    }

    public static void main(String[] args) throws Exception {
        ScheduleList schedules = new ScheduleList();
        schedules.schedules = new ArrayList<Schedule>();
        schedules.schedules.add(new HourlySchedule());
        schedules.schedules.add(new DailySchedule());
        ObjectMapper objectMapper = new ObjectMapper();
        System.out.println(objectMapper.writeValueAsString(schedules));
        String dummySchedule = "{\n" +
                "    \"schedules\": [\n" +
                "        {\n" +
                "            \"type\": \"hourly\",\n" +
                "            \"lastRunTime\": \"DUMMYTIME\",\n" +
                "            \"nextRunTime\": \"MOREDUMMYTIME\",\n" +
                "            \"hour\": \"12\"\n" +
                "        },\n" +
                "        {\n" +
                "            \"type\": \"daily\",\n" +
                "            \"lastRunTime\": \"DUMMYTIME\",\n" +
                "            \"nextRunTime\": \"MOREDUMMYTIME\",\n" +
                "            \"day\": \"1\"\n" +
                "        }\n" +
                "    ]\n" +
                "}";
        ScheduleList parsedSchedule = objectMapper.readValue(dummySchedule, ScheduleList.class);
        System.out.println(parsedSchedule.schedules.get(0).getClass().toString());
        System.out.println(parsedSchedule.schedules.get(1).getClass().toString());
    }
}


@JsonTypeInfo(
        use = JsonTypeInfo.Id.NAME,
        include = JsonTypeInfo.As.PROPERTY,
        property = "type")
@JsonSubTypes({
        @JsonSubTypes.Type(value = DailySchedule.class, name = "daily"),
        @JsonSubTypes.Type(value = HourlySchedule.class, name = "hourly")
})

abstract class Schedule {
    private String lastRunTime;
    private String nextRunTime;

    public String getLastRunTime() {
        return lastRunTime;
    }

    public void setLastRunTime(String lastRunTime) {
        this.lastRunTime = lastRunTime;
    }

    public String getNextRunTime() {
        return nextRunTime;
    }

    public void setNextRunTime(String nextRunTime) {
        this.nextRunTime = nextRunTime;
    }
}

class HourlySchedule extends Schedule {
    private String hour;

    public String getHour() {
        return hour;
    }

    public void setHour(String hour) {
        this.hour = hour;
    }

    @Override
    public String toString() {
        return "HourlySchedule{" +
                "lastRunTime='" + getLastRunTime() + "', " +
                "nextRunTime='" + getNextRunTime() + "', " +
                "hour='" + hour + '\'' +
                '}';
    }
}

class DailySchedule extends Schedule {
    private String day;

    public String getDay() {
        return day;
    }

    public void setDay(String day) {
        this.day = day;
    }

    @Override
    public String toString() {
        return "DailySchedule{" +
                "lastRunTime='" + getLastRunTime() + "', " +
                "nextRunTime='" + getNextRunTime() + "', " +
                "day='" + day + '\'' +
                '}';
    }
}