[SalesForce] Writing JSON using JSONGenerator with writeStringField()

I'm wondering why I can't use the method writeStringField() on the class variables below. I'm using the JSONGenerator class methods instead of hand-constructing the string.

global class VF_MethodRegister {

   public boolean hasCreditCard{get;set;}
   public String cardNumber{get;set;}
   public Integer cardMonth{get;set;}
   public Integer cardYear{get;set;}
   public String cardCVC{get;set;}
   public String email{get;set;}
   public String descr{get;set;}

String kt = ApexPages.currentPage().getParameters().get('kt');
public String message {get;set;}
private final Contact thisCon;

public VF_MethodRegister(ApexPages.StandardController stdController) {
    this.thisCon = (Contact)stdController.getRecord();
}

public VF_MethodRegister(){}

public void registerCustomer(){
    HttpRequest req = new HttpRequest();
    HttpResponse res = new HttpResponse();
    Http h = new Http();    

    Oauth_Settings__c endo = Oauth_Settings__c.getValues('Method_Reg');   // get the    endpoint from custom settings
    String endp = endo.Endpoint__c;

    JSONGenerator jgen = JSON.createGenerator(true);
    jgen.writeStartObject();
    jgen.writeFieldName('Card');
    jgen.writeStartArray();
    jgen.writeStringField('number', cardNumber);   //this line fails upon running
    jgen.writeNumberField('month',cardMonth);
    jgen.writeNumberField('year', cardYear);
    jgen.writeStringField('CVC', cardCVC);
    jgen.writeEndArray();
    jgen.writeStringField('PersonalID', kt);
    jgen.writeStringField('email', email);
    jgen.writeStringField('RegistrationFrom', 'apex');
    jgen.writeEndObject();

I see whem running the debug logs that the values for these variables are set correctly from the page that uses the Extension. But the error I get is Can not write a field name, expecting a value for this line:

 jgen.writeStringField('number', cardNumber);

I've tried also to use jgen.writeStringField('number', cardNumber.toString()); but that didn't work.

What would be the correct method of getting the values from the class variables into the JSON? Other than hand-constructing the string (my first time using the JSONGenerator class).

Best Answer

Rather than manually constructing the JSON, providing the names you need to use in the JSON are legal Apex identifiers you can leave it to the platform to build the correct serialization and just use simple Apex classes:

global class VF_MethodRegister {

    public class Message {
        public Item[] Card;
        public String PersonalID;
        public String email;
        public String RegistrationFrom;
    }

    public class Item {
        public String number;
        public Integer month;
        public Integer year;
        public String CVC;
    }

    private statuc String toJsonString(Message m) {
        return JSON.serializePretty(m);
    }

In your case you would have to transfer the values from the class fields to these simple objects first.

Related Solutions

[SalesForce] Split a single field into 2 columns for a VF page

This is untested so you may need to have play, however this should return a List of the RevenueWrapper classes which contains the 4 columns you are looking to use in your VF page:

public class RevenueController{

Map<String, RevenueWrapper> ResultList = new Map<String, RevenueWrapper>(); 

public RevenueController(){
    List<AggregateResult> result =  [
    SELECT FISCAL_YEAR(Date__c) Date, Type__c, sum(Amount__c) Amount
    FROM Revenue__c
    GROUP BY FISCAL_YEAR(Date__c), Type__c];

    for(AggregateResult ar : result){

        RevenueWrapper RW = new RevenueWrapper();

        //If the RevenueWrapper already exists grab it from the Map
        if(ResultList.containsKey(String.valueOf(ar.get('Date')))){
            RW = ResultList.get(String.valueOf(ar.get('Date')));
        }

        //Set the amount
        RW.setAmount(ar);

        //Save back to the Map
        ResultList.put(String.valueOf(ar.get('Date')), RW);
    }
}

public List<RevenueWrapper> getResults() {
    return ResultList.values();
}


public class RevenueWrapper{
    public String revenueDate { get; set; }
    public Integer budgetAmount { get; set; }
    public Integer actualAmount { get; set; }
    public Integer varianceFYPercent { set; }
    public Integer varianceFYAmount { set; }

    public RevenueWrapper(){

    }

    public void setAmount(AggregateResult ar){
        revenueDate = String.valueOf(ar.get('Date'));

            //Set the amount value based on type
        if(ar.get('Type__c') == 'Budget'){
            budgetAmount = Integer.valueOf(ar.get('Amount'));
        }else if(ar.get('Type__c') == 'Actual'){
            actualAmount = Integer.valueOf(ar.get('Amount'));
        }else{ //Catch all for a type that isn't recognised
            return;
        }

    }

    public Integer getVarianceFYAmount(){
        return actualAmount - budgetAmount;
    }

    public Decimal getVarianceFYPercent(){
        if(budgetAmount != 0){
            return Decimal.valueOf((Double.valueOf(actualAmount) / Double.valueOf(budgetAmount)) * 100).setscale(1);
        } else{
            return 0;
        }
    }
}

}

[SalesForce] Issues with calling 2 setTest methods in apex test class

As it turns out, I overlooked something very simple. When calling the setTest() methods you need to make sure that variables maintain their state once set and therefore, because I was not declaring my variables as static, they were not maintaining their state and thus the error was being thrown.

Here's the modified controller code:

public class CanNewsChatterFeedController {
    //declare necessary static variables
    static ConnectApi.ChatterGroupPage chatterGrpPg;
    static String theGroupId;

    //empty constructor
    public CanNewsChatterFeedController(){}

    // get first page of news feed
    public static ConnectApi.FeedItemPage getNewsFeed() {
        //get the proper Chatter Group Page
        chatterGrpPg = getCanNewsChatterGrpPg();
       //get the groupId
       theGroupId = chatterGrpPg.groups[0].id;
       //use the groupId to get the feedItems
       ConnectApi.FeedItemPage feedPage = ConnectApi.ChatterFeeds.getFeedItemsFromFeed(null, ConnectApi.FeedType.Record, theGroupId);
       return feedPage;
    }

    //The Id of the ChatterGroup we want to display will be different in the sandbox from what it is in production
    //(production id: 0F9D0000000UGqS in sandbox id:0F9c0000000Chu1), in order to get the feed items we want, 
    //we have to search for the ChatterGroup by name. Since Group Name must be unique,
    //the searchGroups method should only return one ChatterGroupPage with one ChatterGroup
    public static ConnectApi.ChatterGroupPage getCanNewsChatterGrpPg(){
        return ConnectApi.ChatterGroups.searchGroups(null, 'Canada - Corby Scoreboard', null, 1);
    }    

    // build list of wrapped feed items for display in VisualForce
    public static List<FeedItemInfo> getNewsFeedForDisplay() {
        ConnectApi.FeedItemPage feed = getNewsFeed();      
        List<FeedItemInfo> result = new List<FeedItemInfo>();
        for (ConnectApi.FeedItem item : feed.items) {
            result.add(new FeedItemInfo(item));
        }

        return result;
    }


    public PageReference refreshFeed(){
        return null;
    }
}

I hope this helps someone else experiencing the same issue.

Best Answer

Related Solutions

[SalesForce] Split a single field into 2 columns for a VF page

[SalesForce] Issues with calling 2 setTest methods in apex test class

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