JSON DeserializeUntyped Error Invalid conversion from runtime type List<ANY> to Map<String,ANY>

Question

sample JSON string :

'{'+
            '   \"count\":\"1\",'+
            '   \"querycount\":\"1\",'+
            '   \"ranking\":\"adaptive\",'+
            '   \"mindPage\":{'+                  ----->able to access id, res from mindPage
            '       \"id\":\"1\",'+
            '       \"res\":\"1\",'+
            '       \"properties\":{'+            ------>able to access count, href from properties
            '         \"@count\":\"2\",'+
            '         \"href\":\"www.google.com",'+
            '         \"property\":['+          ----->Not able to access its values
            '            {'+
            '               \"revision\":\"2\",'+
            '               \"resid\":\"259\",'+
            '               \"name\":\"mindtouch.page#overview\",'+
            '               \"href\":\"www.google.com",'+
            '               \"etag\":\"259.r2_ts2016-06-20T12:35:33Z\",'+
            '               \"resource-is-deleted\":\"false\",'+
            '               \"resource-rev-is-deleted\":\"false\",'+
            '               \"change-description\":\"page overview\",'+
            '               },'+
            '           },'+
            '        },'+
            '   \"parsedQuery\":\"+(content:(\\\"product2\\\") title:(\\\"product2\\\")^10 path.title:(\\\"product2\\\")^4 '+
  '}';

Apex DeserializeUntyped Map methods:

Map<String, Object> dim = (Map<String, Object>)m.get('mindPage');  //able to get the values of main page
system.debug(' Mind Page Id '+dim.get('id'));
Map<String, Object> properties = (Map<String, Object>)dim.get('properties');   //able to get the values of sub page
system.debug(' Mind Page Id '+properties.get('href'));
Map<String, Object> property = (Map<String, Object>)properties.get('property');   //Error - not able to get the values of second subpage(has array)

Error : System.TypeException: Invalid conversion from runtime type List to Map

Any solution for this?

Answer 1

You will have to use list for arrays in your JSON .Something like below

list<Object> lstproperty = (list<Object>)properties.get('property'); 
//Now loop over this 
for(Object propertyObj:lstproperty){
    Map<String, Object> property = (Map<String, Object>)propertyObj;
}