convert a Date/Time field for any timezone

Salesforce saves the date/time fields on GMT Timezone. It is difficult to the users who works on different time zones. Here is solution

create a formula field that calculates the time based on the timzone. Please try the below example. The example which i showed you will work for PST.  if needed to use that in IST change the values (-7 & -8) to 5.5

IF ( DATEVALUE(CreatedDate) >=
DATE ( YEAR (DATEVALUE(CreatedDate)),3,1)
+
(14-
CASE( MOD(DATE ( YEAR (DATEVALUE(CreatedDate)),3,1) - DATE (1900,1,7),7) ,
0,7,MOD(DATE ( YEAR (DATEVALUE(CreatedDate)),3,1) - DATE (1900,1,7),7))
)
&&
DATEVALUE(CreatedDate) <
DATE ( YEAR (DATEVALUE(CreatedDate)),11,1)
+
(7-
CASE( MOD(DATE ( YEAR (DATEVALUE(CreatedDate)),11,1) - DATE (1900,1,7),7) ,
0,7,MOD(DATE ( YEAR (DATEVALUE(CreatedDate)),11,1) - DATE (1900,1,7),7))
),
LEFT ( TEXT (CreatedDate- 7/24 ), 16),
LEFT ( TEXT (CreatedDate- 8/24), 16)
)

Test Class for Asynchronous Callouts using Continuation Class

Write test class and meet the test code coverage for deploy or managed package. Since apex tests doesnot supports the callouts. We use mock responses.

To simulate callouts in continuations, call these methods of the Test class:
setContinuationResponse(requestLabel, mockResponse) and
invokeContinuationMethod(controller, request).

public with sharing class ContinuationController {
    // Unique label corresponding to the continuation request
    public String requestLabel;
    // Result of callout
    public String result {get;set;}
    // Endpoint of long-running service
    private static final String LONG_RUNNING_SERVICE_URL = '';
   
   // Action method
    public Object startRequest() {
      // Create continuation with a timeout
      Continuation con = new Continuation(40);
      // Set callback method
      con.continuationMethod='processResponse';
      
      // Create callout request
      HttpRequest req = new HttpRequest();
      req.setMethod('GET');
      req.setEndpoint(LONG_RUNNING_SERVICE_URL);
      
      // Add callout request to continuation
      this.requestLabel = con.addHttpRequest(req);
      
      // Return the continuation
      return con;  
    }
    
    // Callback method 
    public Object processResponse() {   
      // Get the response by using the unique label
      HttpResponse response = Continuation.getResponse(this.requestLabel);
      // Set the result variable that is displayed on the Visualforce page
      this.result = response.getBody();
      
      // Return null to re-render the original Visualforce page
      return null;
    }
}

This example shows the test class corresponding to the controller. This test class contains a test method for testing an asynchronous callout. In the test method, Test.setContinuationResponse sets a mock response, andTest.invokeContinuationMethod causes the callback method for the continuation to be executed. The test ensures that the callback method processed the mock response by verifying that the controller’s result variable is set to the expected response.

@isTest
public class ContinuationTestingForHttpRequest {
    public static testmethod void testWebService() {
        ContinuationController controller = new ContinuationController();
        // Invoke the continuation by calling the action method
        Continuation conti = (Continuation)controller.startRequest();
        
        // Verify that the continuation has the proper requests
        Map requests = conti.getRequests();
        system.assert(requests.size() == 1);
        system.assert(requests.get(controller.requestLabel) != null);
        
        // Perform mock callout 
        // (i.e. skip the callout and call the callback method)
        HttpResponse response = new HttpResponse();
        response.setBody('Mock response body');   
        // Set the fake response for the continuation     
        Test.setContinuationResponse(controller.requestLabel, response);
        // Invoke callback method
        Object result = Test.invokeContinuationMethod(controller, conti);
        // result is the return value of the callback
        System.assertEquals(null, result);
        // Verify that the controller's result variable
        //   is set to the mock response.
        System.assertEquals('Mock response body', controller.result);
    }
}

Make Long-Running Callouts from a Visualforce Page using Continuation Class

Use asynchronous callouts to make long-running requests from a Visualforce page to an external Web service and process responses in callback methods. Asynchronous callouts that are made from a Visualforce page don’t count toward the Apex limit of 10 synchronous requests that last longer than five seconds. As a result, you can make more long-running callouts and you can integrate your Visualforce pages with complex back-end assets.
An asynchronous callout is a callout that is made from a Visualforce page for which the response is returned through a callback method. An asynchronous callout is also referred to as a continuation.

public with sharing class ContinuationController {
    // Unique label corresponding to the continuation
    public String requestLabel;
    // Result of callout
    public String result {get;set;}
    // Callout endpoint as a named credential URL 
    // or, as shown here, as the long-running service URL
    private static final String LONG_RUNNING_SERVICE_URL = 
        '';
   
   // Action method
    public Object startRequest() {
      // Create continuation with a timeout
      Continuation con = new Continuation(40);
      // Set callback method
      con.continuationMethod='processResponse';
      
      // Create callout request
      HttpRequest req = new HttpRequest();
      req.setMethod('GET');
      req.setEndpoint(LONG_RUNNING_SERVICE_URL);
      
      // Add callout request to continuation
      this.requestLabel = con.addHttpRequest(req);
      
      // Return the continuation
      return con;  
    }
    
    // Callback method 
    public Object processResponse() {   
      // Get the response by using the unique label
      HttpResponse response = Continuation.getResponse(this.requestLabel);
      // Set the result variable that is displayed on the Visualforce page
      this.result = response.getBody();
      
      // Return null to re-render the original Visualforce page
      return null;
    }
}

Read CSV file from documents and create records

Please try the below example. Create a csv file on documents and use the below code to create records.

Document doc=[SELECT Body,ContentType,Description,DeveloperName,Name FROM Document WHERE Name = 'Csv File'];
String[] columns=doc.Body.toString().split('\n');
String[] columnNames=columns[0].split(',');
columns.remove(0);
List<Sobject> lstAccounts=new List<Sobject>();
for(String str:columns)
{
	Account acc=new Account();
	String[] fields=str.split(',');
	for(Integer i=0;i<fields.size();i++)
	{
		acc.put(columnNames[i].trim(),fields[i]);
	}
	lstAccounts.add(acc);
}
if(!lstAccounts.isEmpty())
{
	insert lstAccounts[0];
}

Salesforce Rest Api

Force.com REST API provides you with a powerful Web services API that you can use to interact with Force.com.

Each resource in REST API is a named URI that’s used with an HTTP method: HEAD, GET, POST, PATCH, or DELETE. All resources are accessed using a generic interface over HTTP with a base URI that follows your Force.com or Database.com URI. REST API supports authentication using OAuth 2.0 and supports both JSON and XML (JSON is the default).

To test the Salesforce Rest API. login to workbench. Navigate to utilities-> Rest Explorer and follow below examples to create/update/upsert/delete records. 

 Create a record:
Url:https://instance.salesforce.com/services/data/vNN.N/sobjects/sObject
Method:POST
Request Body:field-value pairs
eg:

url:https://ap1.salesforce.com/services/data/v37.0/sobjects/case
Request Body:{
"Origin": "SMS Feedback",
"Subject": "134350/Feedback",
"Description": "Payment Type: Credit Card "
}

Update a Record
Url:https://instance.salesforce.com/services/data/vNN.N/sobjects/sObject/Id 
Method:PATCH 
Request Body:field-value pairs 
eg:

url:https://ap1.salesforce.com/services/data/v37.0/sobjects/case/500260000045ffRAAQ
Request Body:{
"Origin": "SMS Feedback",
"Subject": "134350/Feedback",
"Description": "Payment Type: Credit Card "
}

Upsert a Record
Url:https://instance.salesforce.com/services/data/vNN.N/sobjects/sObject/externalIdField/value Method:PATCH 
Request Body:field-value pairs 
eg:

url:https://ap1.salesforce.com/services/data/v37.0/sobjects/case/externalfield__c/54364
Request Body:{
"Origin": "SMS Feedback",
"Subject": "134350/Feedback",
"Description": "Payment Type: Credit Card "
}

Delete a Record
https://instance.salesforce.com/services/data/vNN.N/sobjects/sObject/Id Method:DELETE 
eg:

url:https://ap1.salesforce.com/services/data/v37.0/sobjects/case/500260000045fesAAA

Salesforce Limits Class Methods

Salesforce developers often face the issue with governor limits provided by salesforce.

Below are the commonly used limits class methods in order to check the limits

System.debug('Limits.getAggregateQueries==>'+Limits.getAggregateQueries());
System.debug('Limits.getLimitAggregateQueries==>'+Limits.getLimitAggregateQueries());
System.debug('Limits.getCallouts==>'+Limits.getCallouts());
System.debug('Limits.getLimitCallouts==>'+Limits.getLimitCallouts());
System.debug('Limits.getCpuTime==>'+Limits.getCpuTime());
System.debug('Limits.getLimitCpuTime==>'+Limits.getLimitCpuTime());
System.debug('Limits.getDMLRows==>'+Limits.getDMLRows());
System.debug('Limits.getLimitDMLRows==>'+Limits.getLimitDMLRows());
System.debug('Limits.getDMLStatements==>'+Limits.getDMLStatements());
System.debug('Limits.getLimitDMLStatements==>'+Limits.getLimitDMLStatements());
System.debug('Limits.getEmailInvocations==>'+Limits.getEmailInvocations());
System.debug('Limits.getLimitEmailInvocations==>'+Limits.getLimitEmailInvocations());
System.debug('Limits.getFutureCalls==>'+Limits.getFutureCalls());
System.debug('Limits.getLimitFutureCalls==>'+Limits.getLimitFutureCalls());
System.debug('Limits.getHeapSize==>'+Limits.getHeapSize());
System.debug('Limits.getLimitHeapSize==>'+Limits.getLimitHeapSize());
System.debug('Limits.getMobilePushApexCalls==>'+Limits.getMobilePushApexCalls());
System.debug('Limits.getLimitMobilePushApexCalls==>'+Limits.getLimitMobilePushApexCalls());
System.debug('Limits.getQueries==>'+Limits.getQueries());
System.debug('Limits.getLimitQueries==>'+Limits.getLimitQueries());
System.debug('Limits.getQueryLocatorRows==>'+Limits.getQueryLocatorRows());
System.debug('Limits.getLimitQueryLocatorRows==>'+Limits.getLimitQueryLocatorRows());
System.debug('Limits.getQueryRows==>'+Limits.getQueryRows());
System.debug('Limits.getLimitQueryRows==>'+Limits.getLimitQueryRows());
System.debug('Limits.getQueueableJobs==>'+Limits.getQueueableJobs());
System.debug('Limits.getLimitQueueableJobs==>'+Limits.getLimitQueueableJobs());
System.debug('Limits.getSoslQueries==>'+Limits.getSoslQueries());
System.debug('Limits.getLimitSoslQueries==>'+Limits.getLimitSoslQueries());

Salesforce Collection Types

In Salesforce we have 3 collection types

• List
• Map
• Set

List

• Ordered collection of typed primitives, sObjects, objects, or collections that are distinguished by their indices

// Create an empty list of String
List<String> myList = new List<String>();
myList.add('hi');
String x = myList.get(0);

// Create list of records from a query
List<Account> accs =[SELECT Id, Name FROM Account LIMIT 1000];

Map

• Collection of keyvalue pairs where each unique key maps to a single value. A key can be any primitive data type except Blob and Object, while a value can be a primitive, an sObject, a collection type, or an object.

Map<String,String> MyStrings =new Map<String,String>{'a' => 'b', 'c' =>'d'.toUpperCase()};
Account myAcct = new Account();
Map<Integer, Account> m =new Map<Integer,Account>();
m.put(1, myAcct);

Set

• Unordered collection that doesn’t contain any duplicate elements.

Set<Integer> s = new Set<Integer>();
s.add(12);
s.add(12);
System.assert(s.size()==1);

Salesforce Trigger Context Variables

Variable	Operators
isExecuting	Returns true if the current context for the Apex code is a trigger only
isInsert	Returns true if this trigger was fired due to an insert operation
isUpdate	Returns true if this trigger was fired due to an update operation
isDelete	Returns true if this trigger was fired due to a delete operation
isBefore	Returns true if this trigger was fired before any record was saved
isAfter	Returns true if this trigger was fired after all records were saved
isUndelete	Returns true if this trigger was fired after a record was recovered from the Recycle Bin
new	Returns a list of the new versions of the sObject records.(This sObject list is available only in insert and update triggers. The included records can be modified only in before triggers.)
newMap	A map of IDs to the new versions of the sObject records. (Only available in before update, after insert, and after update triggers.)
old	Returns a list of the old versions of the sObject records. (Only available in update and delete triggers.)
oldMap	A map of IDs to the old versions of the sObject records. (Only available in update and delete triggers.)
size	The total number of records in a trigger invocation, both old and new.

 

Salesforce annotations

@future

• Denotes methods that are executed asynchronously.

global class MyFutureClass {
 @future
 static void myMethod(String a, Integer i) {
  System.debug('Method called with: ' + a +' and ' + i);
  // do callout, or execute
  // other long-running code
 }
}

@isTest

• Denotes classes that only contain code used for testing your application. These classes don’t count against the total amount of Apex used by your organization.

@isTest
private class MyTest {
 // Methods for testing
}

@isTest(OnInstall=true)

• Denotes a test class or test method that executes on package installation

@isTest(OnInstall=true)
private class TestClass {
}

@isTest(SeeAllData=true)

• Denotes a test class or test method that has access to all data in the organization, including pre-existing data that the test didn't create. The default is false

@isTest(SeeAllData=true)
private class TestClass {
}

@deprecated

• Denotes methods, classes, exceptions, enums, interfaces, or variables that can no longer be referenced in subsequent releases of the managed package in which they reside

@deprecated
public void limitedShelfLife() {
}

@readOnly

• Denotes methods that can perform queries unrestricted by the number of returned rows limit for a request

@readOnly
private void doQuery() {
}

@remoteAction

• Denotes Apex controller methods that JavaScript code can call from a Visualforce page via JavaScript remoting. The method must be static and either public or global.

@remoteAction
global static String getId(String s) {
}

@restResource

• Denotes a class that is available as a REST resource. The class must be global. The urlMapping parameter is your resource's name and is relative to https:// instance. salesforce. com/services/ apexrest/.

@restResource(urlMapping='/Widget/*')
global with sharing class MyResource() {
}

@httpGet,
@httpPost,
@httpPatch,
@httpPut,
@httpDelete

• Denotes a REST method in a class annotated with @restResource that the runtime invokes when a client sends an HTTPGET, POST, PATCH, PUT, orDELETE respectively. The methods defined with any of these annotations must be global and static.

@httpGet
global static MyWidget__c doGet()
{
}
@httpPost
global static void doPost() {
}
@httpDelete
global static void doDelete() {
}