this is my code but its not woking. any one can help

global class LeadProcessor implements Database.Batchable<sObject> {
    global Database.QueryLocator start(Database.BatchableContext bc){
          String query= 'SELECT Name, LeadSource from Lead';
        return Database.QueryLocator(query);
    }
    global void execute(Database.BatchableContext bc, List<Lead> scope){
        
        for(Lead l: scope){
            l.LeadSource ='Dreamforce';
           
        }
        update scope;
    }
    global void finish(Database.BatchableContext bc){
        
    }
}

Hello everyone I could use some help on the using future Methods trailhead. Please keep in mind I am not an Apex coder at all but I am trying to learn as much as I can.

Here is the Task

Create an Apex class with a method using the @future annotation that accepts a List of Account IDs and updates a custom field on the Account object with the number of contacts associated to the Account. Write unit tests that achieve 100% code coverage for the class.
Create a field on the Account object called 'Number_of_Contacts__c' of type Number. This field will hold the total number of Contacts for the Account.
Create an Apex class called 'AccountProcessor' that contains a 'countContacts' method that accepts a List of Account IDs. This method must use the @future annotation.
For each Account ID passed to the method, count the number of Contact records associated to it and update the 'Number_of_Contacts__c' field with this value.
Create an Apex test class called 'AccountProcessorTest'.
The unit tests must cover all lines of code included in the AccountProcessor class, resulting in 100% code coverage.
Run your test class at least once (via 'Run All' tests the Developer Console) before attempting to verify this challenge.

I have written an Apex class and a Test class but I think I am doing them both Wrong: because when I try to check the challenge i Get this error

Challenge Not yet complete... here's what's wrong: 
The 'AccountProcessorTest' test class doesn't appear to be calling the 'AccountProcessor.countContacts' method between Test.startTest() and Test.stopTest().

When I run the Test class I get this error :

System.QueryException: List has no rows for assignment to SObject

Here is the CLASS:
 

public class AccountProcessor {
     @future

  public static void someFutureMethod(List<id> scope) {

   Account[] updates = new Account[] {};
        for (AggregateResult ar : [
                select AccountId a, count(Id) c
                from Contact
                where AccountId in :scope
                group by AccountId
                ]) {
            updates.add(new Account(
                    Id = (Id) ar.get('a'),
                    Number_of_Contacts__c = (Decimal) ar.get('c')
                    ));
        }
        update updates;
    }

}

Here is the Test Class:
 

@IsTest
public class AccountProcessorTest {
  public static testmethod void TestAccountProcessorTest() {
 
Test.startTest();
     Account a = new Account();
        a.Name = 'Test Account';
        Insert a;
      
      Contact cont = New Contact();
      
      cont.FirstName ='Bob';
      cont.LastName ='Masters';
      cont.AccountId = a.Id;
      Insert cont;

    Test.stopTest() ;
     Contact ACC = [select AccountId from Contact where id = :a.id LIMIT 1];

 
        System.assert(Cont.AccountId != null);
        System.assertequals(cont.id, ACC.AccountId);

  }}

I have used alot or diffrent google searches to get me this far. But I have not Idea if Im even remotly close to the right answer or not.


 

this is the error i am getting ........please help me

Hello,

This is the trailhead questions which I am trying to solve :

Create an Apex class that returns an array (or list) of formatted strings ('Test 0', 'Test 1', ...). The length of the array is determined by an integer parameter.The Apex class must be called 'StringArrayTest' and be in the public scope.
The Apex class must have a public static method called 'generateStringArray'.
The 'generateStringArray' method must return an array (or list) of strings. Each string must have a value in the format 'Test n' where n is the index of the current string in the array. The number of returned strings is specified by the integer parameter to the 'generateStringArray' method.


Here is my code :

public class StringArrayTest {
    public static List <String> generateStringArray (Integer n) {
       List<String> List1 = new List<String> ();
        for(Integer i=0;i<n;i++) {
          List1.add('\'Test'+ i+'\'' );
  }
        System.debug(List1);
        return List1;
    } 

}


I am getting following error :

Challenge not yet complete... here's what's wrong: 
Executing the 'generateStringArray' method failed. Either the method does not exist, is not static, or does not return the proper number of strings.


I tried it many times but I am not able to solve this problem. Please help. 



 

Hi,
I am not able to understand the below question correctly Please help me out. - 
Create a class that has a method accepting two strings. The method searches for contacts that have a last name matching the first string and a mailing postal code (API name: MailingPostalCode) matching the second. It gets the ID and Name of those contacts and returns them.The Apex class must be called 'ContactSearch' and be in the public scope.
The Apex class must have a public static method called 'searchForContacts'.
The 'searchForContacts' method must accept two incoming strings as parameters, find any contact that has a last name matching the first, and mailing postal code matching the second string. The method should return a list of Contact records with at least the ID and Name fields.
The return type for 'searchForContacts' must be 'List<Contact>'.

create an Apex class that inserts a new account named after an incoming parameter. If the account is successfully inserted, the method should return the account record. If a DML exception occurs, the method should return null?
The Apex class must be called 'AccountHandler' and be in the public scope.
The Apex class must have a public static method called 'insertNewAccount'.
The 'insertNewAccount' method must accept an incoming string as a parameter, name the account after the parameter, insert it into the system and then return the account record.
The 'insertNewAccount' method must also accept an empty string, catch the failed DML and return null.

Hello developer heroes!

I'm working through the Apex modules on Trailhead and can't seem to get past this one: https://developer.salesforce.com/en/trailhead/force_com_programmatic_beginner/apex_triggers/apex_triggers_bulk.

Hopefully this doesn't read like a 'please complete the course for me' kinda post, but I have written a trigger that I believe meets the criteria but it isn't passing the check, so I wanted to seek the guidance of the experts.

The challenge is to do this:

Create an Apex trigger for Opportunity that adds a task to any opportunity set to 'Closed Won'.

To complete this challenge, you need to add a trigger for Opportunity. The trigger will add a task to any opportunity inserted or updated with the stage of 'Closed Won'. The task's subject must be 'Follow Up Test Task'.The Apex trigger must be called 'ClosedOpportunityTrigger'

- With 'ClosedOpportunityTrigger' active, if an opportunity is inserted or updated with a stage of 'Closed Won', it will have a task created with the subject 'Follow Up Test Task'.
- To associate the task with the opportunity, fill the 'WhatId' field with the opportunity ID.
- This challenge specifically tests 200 records in one operation.

And here is the trigger I have come up with, which compiles OK and stands up to a manual (though admittedly unbulkified) test:

trigger ClosedOpportunityTrigger on Opportunity (after insert, after update) {

    List<Task> taskList = new List<Task>();
    
    for (Opportunity opp : [SELECT Id, StageName FROM Opportunity WHERE StageName = 'Closed Won' AND Id IN :Trigger.new]){
                    
            taskList.add(new Task(Subject = 'Follow Up Test Task',
                                  WhatId = opp.Id));
       
    }

    if(taskList.size()>0){
        
        insert taskList;
        
    }
    
}

I have tried replacing the SOQL with a straightforward 'for (Opportunity opp : Trigger.new)' and having the taskList.add inside an IF that checks for Closed Won - no luck. I also thought about checking to see if the stage was being changed to Closed Won, rather than the trigger firing on every edit, but I don't think this is what the module is asking for.

Where do you think I'm going wrong?

Huge thanks in advance!