Lightning Datatable example salesforce

Lightning Datatable example salesforce

Lightning Datatable example salesforce

In this blog post, I am going to explain how to use salesforce lightning:datatable component and its features. A lightning:datatable component displays tabular data where each column can be displayed based on the data type. lightning:datatable also supports inline editing. lightning:datatable is not supported on mobile devices. Following are some main features of lightning:datatable

  • Displaying and formatting of columns with appropriate data types
  • Infinite scrolling of rows
  • Inline editing for some data types
  • Header-level actions
  • Row-level actions
  • Resizing of columns
  • Selecting of rows
  • Sorting of columns by ascending and descending order
  • Text wrapping and clipping
  • Row numbering column
  • Cell content alignment


Tables can be populated during initialization using the data, columns, and keyField attributes. The keyField attribute is required for correct table behavior. It will associate each row with a unique identifier. The below code shows how to use the lightning: datatable to initialize the data and columns which are passed by using attributes.

In this example, we will simply display list of account using lightning:datatable.

Apex class AccountController

public class AccountController{
    public static List <Account> fetchAccounts() {
        //Qyery 10 accounts
        List<Account> accList = [SELECT Id, Name, BillingState, 
                                    Website, Phone, Industry, Type from Account LIMIT 10];
        //return list of accounts
        return accList;

Lightning Component LightningDatatableExample

<aura:component controller="AccountController">
    <aura:attribute type="Account[]" name="acctList"/>
    <aura:attribute name="mycolumns" type="List"/>
    <aura:handler name="init" value="{!this}" action="{!c.fetchAcc}"/>
    <lightning:datatable data="{! v.acctList }" 
                         columns="{! v.mycolumns }" 

Lightning Component LightningDatatableExample Controller

    fetchAcc : function(component, event, helper) {
        helper.fetchAccHelper(component, event, helper);

Lightning Component LightningDatatableExample Helper

	fetchAccHelper : function(component, event, helper) {
        component.set('v.mycolumns', [
            {label: 'Account Name', fieldName: 'Name', type: 'text'},
                {label: 'Industry', fieldName: 'Industry', type: 'text'},
                {label: 'Phone', fieldName: 'Phone', type: 'Phone'},
                {label: 'Website', fieldName: 'Website', type: 'url '}
        var action = component.get("c.fetchAccounts");
        action.setCallback(this, function(response){
            var state = response.getState();
            if (state === "SUCCESS") {
                component.set("v.acctList", response.getReturnValue());

Lightning Application LightningDatatableExample

<aura:application extends="force:slds">


Lightning Datatable example Output

Lightning Datatable example salesforce output

Lightning Datatable example salesforce output


Use the following column properties to customize the behavior and visual aspects of your columns.

actionsobjectAppends a dropdown menu of actions to a column. You must pass in a list of label-name pairs.
cellAttributesobjectProvides additional customization, such as horizontal alignment or appending an icon to the output. For more information about alignment, see Aligning Data in a Column. For more information about adding icons, see Appending an Icon to Column Data.
editablebooleanSpecifies whether a column supports inline editing. The default is false.
fieldNamestringRequired. The name that binds the columns properties to the associated data. Each columns property must correspond to an item in the data array.
fixedWidthintegerSpecifies the width of a column in pixels and makes the column non-resizable.
iconNamestringThe Lightning Design System name of the icon. Names are written in the format standard:opportunity. The icon is appended to the left of the header label.
initialWidthintegerThe width of the column when it's initialized, which must be within the minColumnWidth and maxColumnWidth values, or within 50px and 1000px if they are not provided.
labelstringRequired. The text label displayed in the column header.
sortablebooleanSpecifies whether the column can be sorted. The default is false.
typestringRequired. The data type to be used for data formatting. For more information, see Formatting with Data Types.
typeAttributesobjectProvides custom formatting with component attributes for the data type. For example, currencyCode for the currency type. For more information, see Formatting with Data Types.

For more details please refer below official link lightning datatable

Happy Coding 🙂

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Difference between WhoId and WhatId

Difference between WhoId and WhatId

What is difference between WhoId and WhatId?

Difference between WhoId and WhatId

  • WhoID in Salesforce refers to people things. So that would be typically a Lead ID or a Contact ID. The WhoId represents a human such as a lead or a contact. WhoIds are polymorphic. Polymorphic means a WhoId is equivalent to a contact’s ID or a lead’s ID. The label is Name.


  • WhatID in Salesforce refers to object type things.  That would typically be an Account ID or an Opportunity ID. The WhatId represents nonhuman objects such as accounts, opportunities, campaigns, cases, or custom objects. WhatIds are polymorphic. Polymorphic means a WhatId is equivalent to the ID of a related object. The label is Related To.


Please check below image for the object diagram:

Difference between WhoId and WhatId

Difference between WhoId and WhatId


These fields are available on Task and Event Object. In SOQL query these fields can simply be queries similar to other fields.

For more details refer to below link

Happy Coding:)



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Use Lightning Components in Visualforce Pages

Use Lightning Components in Visualforce Pages

Use Lightning Components in Visualforce Pages

How To Display Lightning Component In Visualforce Page

In this post, we will see how we can use Lightning Components in Visualforce Pages or how to display Lightning Component In Visualforce Page. Even though the use of lightning is growing day by day, still some customers are using salesforce classic because of many reasons. Sometimes there is a requirement to use lightning component in visualforce page.

Lightning Components for Visualforce is based on Lightning Out, a powerful and flexible feature that lets you embed Lightning components into almost any web page. When used with Visualforce, some of the details become simpler. For example, you don’t need to deal with authentication, and you don’t need to configure a Connected App.

In this example, we will see a very basic example of the lightning component and then display lightning component in the visualforce page.

Lightning Component LightExample1

        <h1> This is lightning component for visualforce page</h1>

Lightning App LightExampleApp1

Here important point is that ltng:outApp needs to be extended in app.

ltng:outApp adds SLDS resources to the page to allow our Lightning components to be styled with the Salesforce Lightning Design System. If we don’t want SLDS resources added to the page, we need to extend from ltng:outAppUnstyled instead.

<aura:application extends="ltng:outApp" access="GLOBAL">
    <aura:dependency resource="c:LightExample1" />

Visualforce page LightningExampleVF1

<apex:page showHeader="false" sidebar="false">
    <apex:includeLightning />    
    <apex:includeScript value="/lightning/lightning.out.js" />
    <div id="LightningComponentid" />    
    $Lightning.use("c:LightExampleApp1", function() {
          function(cmp) {
             console.log('Display Lightning component in visualforce page');

Use Lightning Components in Visualforce Pages output

Use Lightning Components in Visualforce Pages output

Use Lightning Components in Visualforce Pages output


In the above Visualforce page, apex:includeLightning tag imports necessary dependencies and scripts to enable Visualforce to act as Lightning component container.

We can use $Lightning.use() method in JavaScript to refer to Lightning Application which extends ltng:outApp.

We can use $Lightning.createComponent create Lightning Component dynamically.

We can call $Lightning.use() multiple times on a page, but all calls must reference the same Lightning dependency app.

Other Useful links:

We can also pass parameters from visualforce page to lightning component. Check wrapper class in lightning component salesforce link.

For more details please refer the official documentation link

Please check Salesforce lightning link for more posts related to lightning.

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wrapper class in lightning component salesforce

wrapper class in lightning component salesforce

wrapper class in lightning component salesforce

A wrapper or container class is a class, a data structure, or an abstract data type which contains different objects or collection of objects as its members. In this post we will see how we can use wrapper class in lightning component to display data in lightning component. For details about how we can use wrapper class in visualforce page  check wrapper class in Apex

Let’s see an example of wrapper class in lightning component salesforce. In this example, we will create AcoountContactWrapper and will display account and contact details and display on lightning component.

Apex class controller with the wrapper class


public class AccountContactController{
    public static AccountContactListWrapper getAccountWithContacts(String accountId){
        AccountContactListWrapper accWrapper = new AccountContactListWrapper();
        List<Account> accList = [SELECT Id, Name, BillingState, Website, Phone,
                                    (SELECT Id, FirstName, LastName, Email From Contacts)
                                    FROM Account WHERE Id =: accountId];
            accWrapper.accRecord = accList[0];
            accWrapper.contactList = accList[0].Contacts;
            accWrapper.contactCount = accList[0].Contacts.size();
        return accWrapper;
    // wrapper class with @AuraEnabled and {get;set;} properties 
    public class AccountContactListWrapper{
        public Account accRecord{get;set;}
        public List<Contact> contactList{get;set;}
        public Integer contactCount{get;set;}

Lightning component AccountContactWrapperExample

<aura:component controller="AccountContactController" implements="force:hasRecordId">  
    <aura:handler name="init" value="{!this}" action="{!c.initData}"/>
    <!-- Attributes declaration-->  
    <aura:attribute name="accountContactWrapper" type="object"/>
    <aura:attribute name="recordId" type="Id" />
    <div class="slds-p-around--large">
        <h1 style="font-size:25px;">{!v.accountContactWrapper.accRecord.Name}</h1> 
        <p style="color:red">Total Contacts = {!v.accountContactWrapper.contactCount}</p>
    <table class="slds-table slds-table--bordered slds-table--cell-buffer">
            <tr class="slds-text-title--caps">
                <th scope="col">
                    <div class="slds-truncate" title="First Name">First Name</div>
                <th scope="col">
                    <div class="slds-truncate" title="First Name">Last Name</div>
                <th scope="col">
                    <div class="slds-truncate" title="Email">Email</div>
            <aura:iteration items="{!v.accountContactWrapper.contactList }" var="con">
                    <th scope="row">
                        <div class="slds-truncate" title="{!con.FirstName}">{!con.FirstName}</div>
                    <th scope="row">
                        <div class="slds-truncate" title="{!con.LastName}">{!con.LastName}</div>
                    <th scope="row">
                        <div class="slds-truncate" title="{!con.Email}">{!con.Email}</div>

Javascript controller for lightning component AccountContactWrapperExample

    initData: function(component, event, helper) {
        console.log('***In controller');
        helper.getAccountContactWrapperhelper(component, event, helper);

Helper for lightning component AccountContactWrapperExample

    getAccountContactWrapperhelper: function(component, event, helper) {
      console.log('***In helper');
      var a= component.get("v.recordId");
      console.log('***In helper'+a);
      //call apex class method
      var action = component.get('c.getAccountWithContacts');
            accountId : component.get("v.recordId")
      action.setCallback(this, function(response) {
        //store state of response
        var state = response.getState();
        if (state === "SUCCESS") {
          //set response value in wrapperList attribute on component.
          component.set('v.accountContactWrapper', response.getReturnValue());

Lightning App AccountContactWrapperExampleApp

<aura:application access="GLOBAL" extends="ltng:outApp">
    <aura:dependency resource="c:AccountContactWrapperExample"/>

Visualforce page AccountContactWrapperExampleVF

<apex:page showHeader="false">
    <apex:includeLightning />    
    <apex:includeScript value="/lightning/lightning.out.js" />
    <div id="accountContactWrapperId" >
    $Lightning.use("c:AccountContactWrapperExampleApp", function() {
        recordId :"{!$}"
        function(cmp) {
        console.log('Display Lightning component in visualforce page');


Testing visualforce page by passing record id in parameter. In my case URL is:


Output will be like this:

wrapper class in lightning component salesforce output

wrapper class in lightning component salesforce output


Important: Previously it was possible to use inner wrapper class attribute like this:

<aura:attribute name="accountContactWrapper" type="AccountContactController.AccountContactListWrapper"/>

Problem is Lightning components can’t use inner classes as attribute type when the org has setup a namespace. For more details refer below known issue link.

But now it does not work and we have to use Object as type.

<aura:attribute name="accountContactWrapper" type="object"/>

Happy Coding:)

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Salesforce Integration Interview questions and answers

Salesforce Integration Interview questions and answers

In this post I am going to share Salesforce Integration Interview questions and answers

Salesforce Integration Interview questions and answers

What is Integration?

Integration is a process of connecting two applications. A typical enterprise uses many applications, many or most of which are not designed to work with one another out of the box. Integrating separate but related apps helps organizations achieve greater levels of operational consistency, efficiency, and quality. Each application can have data, business logic, presentation, and security layers, all of which are possible targets for integration. This page is an overall launch point for exploring the various integration options related to and other Salesforce platform technologies.

What are possible Ways to Integrate with Salesforce

  • User Interface Integration: Combine the UIs of two or more apps to create composite apps with little or no rework on the UI of each individual app. One example is using Canvas
  • Business Logic Integration: It uses Apex Web Services for Inbound and Apex Callouts for Outbound. It typically handles a scenario where business logic is spread across several applications to implement the complete end-to-end business process. An example would be building complex logic on the data received before committing it into Salesforce.
  • Data Integration:It uses SOAP APIs and REST APIs. It typically handles data synchronization requirements, where one application in an enterprise acts as the primary source for a particular business object, like Account.


What is webservices?

Webservices is a functionality or code which helps to us to do integration. Web services are open standard (XML, SOAP, HTTP, etc.) based web applications that interact with other web applications for the purpose of exchanging data. Web services can convert your existing applications into web applications.

What is Protocal ?

Protocal is a set of mutually accepted and implemented rules at both ends of the communications channel for the proper exchange of information.

How many types of API’s avaliable in salesforce?

  • Bulk API
  • Streaming API
  • Metadata API
  • Chatter REST API
  • User Interface API
  • Analytics REST API
  • Apex REST API
  • Apex SOAP API
  • Tooling API


When to Use REST API

REST API provides a powerful, convenient, and simple REST-based web services interface for interacting with Salesforce. Its advantages include ease of integration and development, and it’s an excellent choice of technology for use with mobile applications and web projects. For certain projects, you may want to use REST API with other Salesforce REST APIs. To build UI for creating, reading, updating, and deleting records, including building UI for list views, actions, and dependent picklists, use User Interface API. To build UI for Chatter, communities, or recommendations, use Chatter REST API. If you have many records to process, consider using Bulk API, which is based on REST principles and optimized for large sets of data.

When to Use SOAP API

SOAP API provides a powerful, convenient, and simple SOAP-based web services interface for interacting with Salesforce. You can use SOAP API to create, retrieve, update, or delete records. You can also use SOAP API to perform searches and much more. Use SOAP API in any language that supports web services.

For example, you can use SOAP API to integrate Salesforce with your org’s ERP and finance systems. You can also deliver real-time sales and support information to company portals and populate critical business systems with customer information.

When to Use Chatter REST API

Use Chatter REST API to display Chatter feeds, users, groups, and followers, especially in mobile applications. Chatter REST API also provides programmatic access to files, recommendations, topics, notifications, purchasing, and more. Chatter REST API is similar to APIs offered by other companies with feeds, such as Facebook and Twitter, but it also exposes Salesforce features beyond Chatter.

Use Chatter REST API to display Chatter feeds, users, groups, and followers, especially in mobile applications. Chatter REST API also provides programmatic access to files, recommendations, topics, notifications, purchasing, and more. Chatter REST API is similar to APIs offered by other companies with feeds, such as Facebook and Twitter, but it also exposes Salesforce features beyond Chatter.

When to Use Streaming API

Use Streaming API to receive near-real-time streams of data that are based on changes in Salesforce records or custom payloads. For Salesforce record changes, Salesforce publishes notifications when the changes occur. For custom notifications, you can publish event messages. Subscribers can receive notifications using CometD—an implementation of the Bayeux protocol that simulates push technology. Clients can subscribe to some types of events with Apex triggers or declaratively with Process Builder and flows.

When to Use Apex REST API

Use Apex REST API when you want to expose your Apex classes and methods so that external applications can access your code through REST architecture. Apex REST API supports both OAuth 2.0 and Session ID for authorization.

When to Use Apex SOAP API

Use Apex SOAP API when you want to expose Apex methods as SOAP web service APIs so that external applications can access your code through SOAP.

Apex SOAP API supports both OAuth 2.0 and Session ID for authorization.

When to Use Tooling API

Use Tooling API to integrate Salesforce metadata with other systems. Metadata types are exposed as sObjects, so you can access one component of a complex type. This field-level access speeds up operations on complex metadata types. You can also build custom development tools for applications. For example, use Tooling API to manage and deploy working copies of Apex classes and triggers and Visualforce pages and components. You can also set checkpoints or heap dump markers, execute anonymous Apex, and access logging and code coverage information.

What is Call In and Call Out?

Call In is used to exposing our webservices to another system.
Call out enables you to tightly integrate your Apex with an external service by making a call to an external Web service or sending a HTTP request from Apex code and then receiving the response.

What is WSDL ?

WSDL (Web Services Description Language) is an XML document that describes a web service. WSDL is derived from Microsoft’s Simple Object Access Protocol (SOAP) and IBM’s Network Accessible Service Specification Language (NASSL). WSDL replaces both NASSL and SOAP as the means of expressing business services in the UDDI registry. It is used in combination with SOAP and XML Schema to provide web services over the Internet. A client program connecting to a web service can read the WSDL to determine what functions are available on the server. Any special datatypes used are embedded in the WSDL file in the form of XML Schema. The client can then use SOAP to actually call one of the functions listed in the WSDL. There are two types of WSDL in  Salesforce:

  • Enterprise WSDL
  • Partner WSDL

What is difference between Enterprise WSDL and Partner WSDL?

Enterprise WSDL

  • The Enterprise WSDL is strongly typed.
  • The Enterprise WSDL is tied (bound) to a specific configuration of Salesforce (ie. a specific organization’s Salesforce configuration).
  • The Enterprise WSDL changes if modifications (e.g custom fields or custom objects) are made to an organization’s Salesforce configuration.

Partner WSDL

  • The Partner WSDL is loosely typed.
  • The Partner WSDL can be used to reflect against/interrogate any configuration of Salesforce (ie. any organization’s Salesforce configuration).
  • The Partner WSDL is static, and hence does not change if modifications are made to an organization’s Salesforce configuration.

How SOAP can be accessed ?

SOAP can be communicate through WSDL file, without WSDL file we can’t do integration.
Message format in SOAP is XML

How to generate WSDL file?

  • Go to Setup -> Develop  -> apex classes
  • Click on Apex class
  • Click on Generate WSDL button
  • Generate WSDL code from class
  • Save as .wsdl file in your system


How to consume external WSDL file

  1. In the application, from Setup, enter Apex Classes in the Quick Find box, then select Apex Classes.
  2. Click Generate from WSDL.
  3. Click Browse to navigate to a WSDL document on your local hard drive or network, or type in the full path. This WSDL document is the basis for the Apex class you are creating.
  4. Click Parse WSDL to verify the WSDL document contents. The application generates a default class name for each namespace in the WSDL document and reports any errors. Parsing fails if the WSDL contains schema types or constructs that aren’t supported by Apex classes, or if the resulting classes exceed the 1 million character limit on Apex classes. For example, the Salesforce SOAP API WSDL cannot be parsed.
  5. Modify the class names as desired. While you can save more than one WSDL namespace into a single class by using the same class name for each namespace, Apex classes can be no more than 1 million characters total.
  6. Click Generate Apex. The final page of the wizard shows which classes were successfully generated, along with any errors from other classes. The page also provides a link to view successfully generated code.

What is remote site settings ?

Remote site settings is used to authorize the endpoint and allow us to whom integrate(end user)

How manys ways to XML parsing ?

They are two ways of XML parsing
1. XML streams

How to read root element in XML DOM ?

getroot element

How to read child element in XML DOM ?

getchild element

How to read all child elements in XML DOM ?

getchild elements

How to read text between tags ?


How SOAP and REST will Communicate ?

SOAP will communicate through WSDL file.
REST will communicate through HTTP protocol.

What are methods in REST

  • HTTPGET : Retrieve data identified by a URL.
  • HTTPPOST : Create a resource or post data to the server.
  • HTTPDELETE : Delete a resource identified by a URL.
  • HTTPPUT : Create or replace the resource sent in the request body.


What is difference between SOAP and REST?

SOAP API: The Simple Object Access Protocol (SOAP) is an attempt to define a standard for creating web service APIs. It is a pattern, a web service architecture, which specifies the basic rules to be considered while designing web service platforms. It typically uses HTTP as a layer 7 protocol, although this is not mandatory.

The SOAP message itself consists of an envelope, inside of which are the SOAP headers and body, the actual information we want to send. It is based on the standard XML format, designed especially to transport and store structured data. SOAP may also refer to the format of the XML that the envelope uses. SOAP is a mature standard and is heavily used in many systems, but it does not use many of the functionality build in HTTP. While some consider it slow, it provides a heavy set of functionality which is a necessity in many cases. It might now be the best solution for browser-based clients, due to its custom format.

  • Supports data in the form of XML only and not JSON.
  • Requires WSDL for the integration
  • Use SOAP API in any language that supports Web services.


REST API: The Representational State Transfer (REST) is another architectural pattern (resource-oriented), an alternative to SOAP. Unlike SOAP, RESTful applications use the HTTP build-in headers (with a variety of media-types) to carry meta information and use the GET, POST, PUT and DELETE verbs to perform CRUD operations. REST is resource-oriented and uses clean URLs (or RESTful URLs).

  • Supports both XML and JSON format
  • Preferred for mobile and web apps since JSON being Lighter the app runs smoother and faster

What is JSON ?

JSON stands for JavaScript Object Notation. JSON is light weighted than XML.  When exchanging data between a browser and a server, the data can only be text. JSON is text, and we can convert any JavaScript object into JSON, and send JSON to the server.


Other Useful links for Salesforce Integration interview questions and answers

Apex Integration Services Trailhead

Other posts related to salesforce interview questions

Salesforce Lightning interview Questions

Salesforce Certified Integration Architecture Designer Exam

I will keep adding more questions to Salesforce Integration Interview questions and answers.

Please add your comments or questions to Salesforce Integration Interview questions and answers.


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salesforce email service

salesforce email service

Salesforce Email service is automated process that use Apex class to process inbound email. When we set up an email service, we need to generate a special email address in which salesforce will receive your emails. We also need to create one apex class to implement Messaging.InboundEmailHandler interface . The email services will then invoke a handleInboundEmail method on the Apex class whenever an email is received on the email address.

salesforce email service example

Lets create very simple email service which will create contact when an email is sent to salesforce.

Steps to create email service

  1. First of all we need to create Apex class that implement the Messaging.InboundEmailHandler interface. Its necessary to implement Messaging.InboundEmailHandler interface. Using the handleInboundEmail method in that class, you can access an InboundEmail object to retrieve the contents, headers, and attachments of inbound email messages, as well as perform many functions. This class will handle email message.
    global class CreateContactFrmEmail implements Messaging.InboundEmailHandler {
        global Messaging.InboundEmailResult handleInboundEmail(Messaging.InboundEmail email,
                                                        Messaging.InboundEnvelope envelope) {
            Messaging.InboundEmailResult result = new Messaging.InboundEmailresult();
            String subToCompare = 'Create Contact';
            List<Attachment> attachmentList = new List<Attachment>();
            if(email.subject.equalsIgnoreCase(subToCompare)) {
                Contact c = new Contact();
                c.LastName = email.plainTextBody;
                insert c;
                // Save attachments, if any
                if(email.textAttachments!=null) {
                    for (Messaging.Inboundemail.TextAttachment tAttachment : email.textAttachments) {
                        Attachment attachment = new Attachment();
                        attachment.Name = tAttachment.fileName;
                        attachment.Body = Blob.valueOf(tAttachment.body);
                        attachment.ParentId = c.Id;
                //Save any Binary Attachment
                    for (Messaging.Inboundemail.BinaryAttachment bAttachment : email.binaryAttachments) {
                        Attachment attachment = new Attachment();
                        attachment.Name = bAttachment.fileName;
                        attachment.Body = bAttachment.body;
                        attachment.ParentId = c.Id;
                    insert attachmentList;
            result.success = true;
            return result;


  2. Create email service:
    Go to setup -> Email Service -> New Email Service. Add following details as per this imagesalesforce email service

    Click on Save or Save and New email address.

  3. Generate an email address from email service record
    Create new email address and add all details as per this image:salesforce email service email address


    Click on save. New email address will be created in related list. We need to send email to generated email address to test email service. You can copy email address from email service related list so that we can use it for testing.

  4. Testing email service by sending email:
    For testing send an email to this email id with subject ‘Create Contact’ and add some body which will be saved in last name. We can also add attachment(its optional) in email. As contact last name is required field on contact object, so it is necessary to enter text body in email.

For more details about email service please this link from salesforce.

Happy coding 🙂

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System.NullPointerException: Attempt to de-reference a null object

System.NullPointerException: Attempt to de-reference a null object

How to solve System.NullPointerException: Attempt to de-reference a null object error

System.NullPointerException: Attempt to de-reference a null object is very common error in apex class.  It occurs when your variable (sobject, list, set or any other data type) is not initialized (allocated memory). In order to use the non primitive data type in the code we need to initialize the memory first. If we don’t do that it may result in Attempt to de-reference a null object error. This error may occur in Apex classes, Visualforce pages with Apex controller, Test classes, Apex Triggers.

For Example if I use like this:

Account acc;
acc.Name = 'sfdcpoint';

It will result in attempt to de-reference a null object error.

We should use it like this:

Account acc = new Account();
acc.Name = 'sfdcpoint';

When we use list or set then also we need to allocate memory to list or set like this

List<Account> accList = new List<Account>();
Set<String> strSet= new Set<String>();

Same way this error can occur when we get null result from map and we try to use it in our code. For example we have accountMap with Id as key and Account as value:

Account accRecord = accountIdAccountMap.get(accId);

Above code will also result in error. Here in above code accountIdAccountMap or  accRecord can be null. So we should do null check before using it like this.

if(accountIdAccountMap != null){
    Account accRecord = accountIdAccountMap.get(accId);
    if(accRecord != null){

It is also very good practice to use isEmpty() method like this:

     //Do your dml or other operations here

As a best practice we should always do exception handling in our code like this

    //Code here
}catch(Exception e){
    //Handle exception here

If you get System.NullPointerException. Its advisable to use System.debug to debug line of code which is resulting in this error and then fix it.

Here are salesforce official link for same error

Error in Apex code trigger

Error in Salesforce CPQ

For salesforc lightning interview questions refer to below link salesforce lightning

Happy coding 🙂

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Assignment rules in Salesforce

Assignment rules in Salesforce

What are assignment rules in salesforce?

Assignment rules are used to automatically assign lead or Case to owner(User Or Queue). Its used to automate owner assignment on Case and Lead based on conditions on Case or Lead.

Types of assignment rules:

  • Lead Assignment Rules  : Specify how leads are assigned to users or queues as they are created manually, captured from the web, or imported via the Data Import Wizard.
  • Case Assignment Rules : Determine how cases are assigned to users or put into queues as they are created manually, using Web-to-Case, Email-to-Case, On-Demand Email-to-Case, the Self-Service portal, the Customer Portal, Outlook, or Lotus Notes.

Create or Setup assignment rules

  1. From Setup, enter Assignment Rules in the Quick Find box, then select either Lead Assignment Rules or Case Assignment Rules.
  2. Choose New, and then give the rule a name. Specify whether you want this to be the active rule for leads or cases created manually and via the web and email. Then click Save.
  3. To create the rule entries, click New. For each entry, you can specify:
  • Order : Sets the order in which the entry will be processed in the rule, for example, 1, 2, 3. Salesforce evaluates each entry in order and tries to match the criteria of the entry. As soon as a match is found, Salesforce processes the item and stops evaluating the rule entries for that item. If no match is found, the item is reassigned to either the default Web-to-Lead owner, the administrator doing a lead import, or the default case owner.
  • Criteria :Specifies conditions that the lead or case must match for it to be assigned.Enter your rule criteria.
      • Choose criteria are met and select the filter criteria that a record must meet to trigger the rule.For example, set a case filter to Priority equals High if you want case records with the Priority field marked High to trigger the rule. If your organization uses multiple languages, enter filter values in your organization’s default language. You can add up to 25 filter criteria, of up to 255 characters each. When you use picklists to specify filter criteria, the selected values are stored in the organization’s default language. If you edit or clone existing filter criteria, first set the Default Language on the Company Information page to the same language that was used to set the original filter criteria. Otherwise, the filter criteria may not be evaluated as expected.
      • Choose formula evaluates to true and enter a formula that returns a value of “True” or “False.” Salesforce triggers the rule if the formula returns “True.” For example, the formula AND(ISCHANGED( Priority ), ISPICKVAL (Priority, “High”) ) triggers a rule that changes the owner of a case when the Priority field is changed to High. If your condition uses a custom field, the rule entry will be deleted automatically if the custom field is deleted.
  • User : Specifies the user or queue to which the lead or case will be assigned if it matches the condition. Users specified here cannot be marked “inactive” and they must have “Read” permission on leads or cases.
  • Do Not Reassign Owner : Specifies that the current owner on a lead or case will not be reassigned to the lead or case when it is updated.
  • Email Template : Specifies the template to use for the email that is automatically sent to the new owner. If no template is specified, no email will be sent. When assigning a lead or case to a queue, the notification goes to the Queue Email address specified for the queue and all queue members.
  • Predefined Case Teams : Specifies the predefined case team(s) to add to a case when it matches the condition. A case team is a group of people that work together to solve cases.
  • Replace any existing predefined case teams on the case : Specifies that any existing predefined case teams on the case are replaced with the predefined case teams on the condition, when a case matches the condition.

After creating the entry, click Save, or Save & New to save the entry and create more entries.

Assignment Rule Example

Following is sample Case assignment rule which assigns case to different queues based on Billing Country, Account SLA and customer type:

Assignment rules in Salesforce

Assignment rules in Salesforce

For more details about assignment rules please refer to assignment rules official link.

Assignment rules in Salesforce trailhead

Good luck for creating Assignment rules in Salesforce 🙂

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Using apex:repeat in Visualforce Page

Using apex:repeat in Visualforce Page

Using apex:repeat in Visualforce Page

apex:repeat is an iteration component that allows you to output the contents of a collection according to a structure that you specify. The collection can include up to 1,000 items.

Note that if used within an <apex:pageBlockSection> or <apex:panelGrid> component, all content generated by a child <apex:repeat> component is placed in a single <apex:pageBlockSection> or <apex:panelGrid> cell.

This component can’t be used as a direct child of the following components:

  • <apex:panelBar>
  • <apex:selectCheckboxes>
  • <apex:selectList>
  • <apex:selectRadio>
  • <apex:tabPanel>


<apex:repeat> tag has following attributes

Attribute Name Attribute Type Description
firstIntegerThe first element in the collection visibly rendered, where 0 is the index of the first element in the set of data specified by the value attribute. For example, if you did not want to display the first two elements in the set of records specified by the value attribute, set first="2".
IdStringAn identifier that allows the repeat component to be referenced by other components in the page.
renderedBooleanA Boolean value that specifies whether the component is rendered on the page. If not specified, this value defaults to true.
rowsIntegerThe maximum number of items in the collection that are rendered. If this value is less than the number of items in the collection, the items at the end of the collection are not repeated.
valueObjectThe collection of data that is iterated over.
varStringThe name of the variable that represents the current item in the iteration.

apex:repeat example

apex:repeat Visualforce page

<apex:page controller="repeatCon" id="thePage">
    <apex:repeat value="{!strings}" var="string" id="theRepeat">
        <apex:outputText value="{!string}" id="theValue"/><br/>

apex:repeat Apex Code

public class repeatCon {
    public String[] getStrings() {
        return new String[]{'ONE','TWO','THREE'};

For more details please refer below official link:


Difference between apex:pageBlockTable and apex:repeat

When we use pageBlockTable then all salesforce styles are inherited. But when we use apex:repeat we have to manually add table tr td tags and all styles. Advantage of using apex:repeat is that we have more control on display of data.

Other similar post for visualforce

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Salesforce Governor Limits

Salesforce Governor Limits

What is Salesforce Governor Limits?

What are governor limits in salesforce?

Salesforce Governor Limits

Apex runtime engine strictly enforces limits to ensure that runaway Apex code or processes don’t monopolize shared resources.

Why Salesforce has Governor Limits?

Because Apex runs in a multitenant environment, the Apex runtime engine strictly enforces limits to ensure that runaway Apex code or processes don’t monopolize shared resources. If some Apex code exceeds a limit, the associated governor issues a runtime exception that cannot be handled.

Type of Governor Limits

  • Per-Transaction Apex Limits
  • Per-Transaction Certified Managed Package Limits
  • Lightning Platform Apex Limits
  • Static Apex Limits
  • Size-Specific Apex Limits
  • Miscellaneous Apex Limit

In this post we will mainly cover Per-Transaction Apex Limits.

These limits count for each Apex transaction. For Batch Apex, these limits are reset for each execution of a batch of records in the execute method.

This table lists limits for synchronous Apex and asynchronous Apex (Batch Apex and future methods) when they are different. Otherwise, this table lists only one limit that applies to both synchronous and asynchronous Apex. This table can be used as cheat sheet.

Here is list of governor limits in salesforce

DescriptionSynchronous LimitAsynchronous Limit
Total number of SOQL queries issued100200
Total number of records retrieved by SOQL queries50,000
Total number of records retrieved by Database.getQueryLocator10,000
Total number of SOSL queries issued20
Total number of records retrieved by a single SOSL query2,000
Total number of DML statements issued150
Total number of records processed as a result of DML statements, Approval.process, or database.emptyRecycleBin10,000
Total stack depth for any Apex invocation that recursively fires triggers due to insert, update, or delete statements16
Total number of callouts (HTTP requests or Web services calls) in a transaction100
Maximum cumulative timeout for all callouts (HTTP requests or Web services calls) in a transaction120 seconds
Maximum number of methods with the future annotation allowed per Apex invocation50
Maximum number of Apex jobs added to the queue with System.enqueueJob50
Total number of sendEmail methods allowed10
Total heap size6 MB12 MB
Maximum CPU time on the Salesforce servers10,000 milliseconds60,000 milliseconds
Maximum execution time for each Apex transaction10 minutes
Maximum number of push notification method calls allowed per Apex transaction10
Maximum number of push notifications that can be sent in each push notification method call2,000

For more details about governor limit, please refer to below link Execution Governors and Limits

Avoiding Governor limits

From a Developer’s perspective, it is important to ensure that our code should be scalable and should not hit the governor limits. Its very important to follow some of best practices so that our code does not hit governor limit. These are some of best practices that we should follow:

  • Bulkify your Code
  • Avoid SOQL Queries or DML statements inside FOR Loops
  • Bulkify your Helper Methods
  • Using Collections, Streamlining Queries, and Efficient For Loops
  • Streamlining Multiple Triggers on the Same Object
  • Querying Large Data Sets
  • Use of the Limits Apex Methods to Avoid Hitting Governor Limits
  • Use @future Appropriately
  • Use batch apex if you are working for more than 50000 records.
  • Never make any SOQL, DML operation inside the loop.

For more details, refer this APEX best Practices

For other Salesforce post, please refer this link

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