Not able to get Distance from google distance matrix JSON format

Question

Hi I am working on calculating distance from one location to another. I got the JSON format from the response but further I am not able to get the distance from JSON in my apex code. I have also taken help from this link Distance calculation API but I got the error Error message: Invalid decimal:. I am getting the response in the below format

{
  "destination_addresses" : [ "New York, NY, USA" ],
  "origin_addresses" : [ "Washington, DC, USA" ],
  "rows" : [
  {
     "elements" : [
        {
           "distance" : {
              "text" : "225 mi",
              "value" : 361993
           },
           "duration" : {
              "text" : "3 hours 52 mins",
              "value" : 13943
           },
           "status" : "OK"
        }
     ]
  }
],
"status" : "OK"
}

Can anyone tell me please how can I get the value of distance: 225 mi I have also looked JSON2Apex but did not understand how would I use that.

Answer 1

If you put your JSON into the JSON2Apex https://json2apex.herokuapp.com/ and generate the class you can add this class into you Org. Than you can call it like:

JSON2APEX a = JSON2Apex.parse('yourJSONString');
System.debug(a.rows[0].elements[0].distance.value);

This will give you the distance. If you look at the auto generated class you will see that the class consists of a List of rows. Therefore, you need one of them (here the first one row[0]. A row again ist a list of elements -> elements[0]. An element class have a distance, a duration and a status. Since you need the distance only and than the value of this distance you can use distance.value

Answer 2

I got the solution from the link which I have posted in my question. I generated a class from Json2Apex and perform all the activity in same class. Below is my code -

public class gettingDistance {
       @AuraEnabled 
       public static String fetchUser(){
           User oUser = [select Id, Name, Location__c FROM User Where id =: userInfo.getUserId()];
           String userName = oUser.Name;
           return userName;
       }

@AuraEnabled
public static Visits__c getgeoLocation(String recordId, String userName){
       Visits__c recordName = [SELECT Id, Name, Distance_km__c, Checked_In_Location__Latitude__s, Checked_In_Location__Longitude__s, Checked_Out_Location__Latitude__s, Checked_Out_Location__Longitude__s FROM Visits__c where Id =: recordId];
       HttpRequest req = new HttpRequest();
       Http http = new Http();
       req.setMethod('GET');
       String url = 'https://maps.googleapis.com/maps/api/distancematrix/json?origins='+recordName.Checked_In_Location__Latitude__s + ',' + recordName.Checked_In_Location__Longitude__s + '&destinations=' + recordName.Checked_Out_Location__Latitude__s + ',' + recordName.Checked_Out_Location__Longitude__s +'&mode=driving&key=*API KEY*'+'&units=metric'+'&language=en'+'&mode=driving';
       req.setEndPoint(url);
       HTTPResponse resp = http.send(req);
       String json = resp.getBody();
       System.debug('Response' +resp.getBody());
       gettingDistance obj = gettingDistance.parse(json);
       gettingDistance.Rows row = (gettingDistance.Rows)obj.rows.get(0);
       gettingDistance.Elements elem = (gettingDistance.Elements)row.elements.get(0);
       gettingDistance.Distance dist = (gettingDistance.Distance)elem.distance;
       String distMile = dist.text;
       Integer distKM = dist.value;
       system.debug('distMile'+ distMile);
       system.debug('distKM'+distKM);
       return recordName;
   }
   public class Elements {
       public Distance distance;
       public Distance duration;
       public String status;
   }
   public class Distance {
       public String text;
       public Integer value;
   }
   public List<String> destination_addresses;
   public List<String> origin_addresses;
   public List<Rows> rows;
   public String status;
   public class Rows {
       public List<Elements> elements;
   }
   public static gettingDistance parse(String json) {
       return (gettingDistance) System.JSON.deserialize(json, gettingDistance.class);
   }
}