What is Apex Programming?

Apex programming is a server-side programming language used by Salesforce.com to develop enterprise-level applications. It is a strongly-typed, object-oriented programming language that allows developers to create custom business logic, integrate with external systems, and extend the functionality of Salesforce.com.

What is an Apex Class?

An Apex class is a blueprint for creating objects in Apex. It is a container for methods, variables, and other code, which can be used to implement business logic or perform custom calculations. Each class in Apex must have a unique name, and it can be either public or private.

How to create an Apex Class?

To create an Apex class in Salesforce.com, follow these steps:

Log in to Salesforce.com and click on the Setup button.
From the Setup menu, select Develop and then click on Apex Classes.
Click on the New button to create a new Apex class.
Enter the name of the class and the code in the editor window.
Save the class by clicking on the Save button.

What is a Constructor in Apex?

A constructor in Apex is a special method that is called when an object is created from a class. It is used to initialize the variables of the class and perform any other necessary setup. Constructors can have parameters, and they must have the same name as the class.

Here is an example of a constructor in Apex:

public class MyClass {

    private String myVariable;

    public MyClass(String myParameter) {

myVariable = myParameter;

    }

}

In this example, the constructor takes a String parameter called myParameter and assigns its value to the private variable myVariable.

What are Apex Triggers?

An Apex trigger is a piece of code that is executed before or after a record is inserted, updated, or deleted in Salesforce.com. Triggers can be used to perform custom actions, such as updating related records or sending emails, when certain events occur.

How to create an Apex Trigger?

To create an Apex trigger in Salesforce.com, follow these steps:

Log in to Salesforce.com and click on the Setup button.
From the Setup menu, select Develop and then click on Apex Triggers.
Click on the New button to create a new Apex trigger.
Enter the name of the trigger and the code in the editor window.
Save the trigger by clicking on the Save button.

What is an Apex Interface?

An Apex interface is a blueprint for creating classes that implement certain methods or behaviour. It defines a set of methods and variables that a class must implement, but it does not provide any implementation details itself. Interfaces are used to enforce a common behaviour across different classes.

Here is an example of an Apex interface:

public interface MyInterface {

    void doSomething();

    String getValue();

}

In this example, the interface defines two methods: doSomething() and getValue(). Any class that implements this interface must provide an implementation for both of these methods.

What are Apex Collections?

An Apex collection is a group of elements of the same data type that are stored in memory. There are three types of collections in Apex: lists, sets, and maps.

A list is an ordered collection of elements that can be accessed by index.
A set is an unordered collection of unique elements.
A map is a collection of key-value pairs, where each key is unique.

Here is an example of a list in Apex:

List<String>myList = new List<String>();

myList.add('apple');

myList.add('banana');

myList.add('orange');

In this example, we created a new list of Strings called myList. We then added three elements to the list using the add() method. The elements are the strings "apple", "banana", and "orange". We can access each element in the list by its index, like this:

String firstElement = myList[0]; // "apple"

String secondElement = myList[1]; // "banana"

String thirdElement = myList[2]; // "orange"

What are Apex Annotations?

An Apex annotation is a special marker used to provide additional information about a class, method, or variable. Annotations are used to control the behaviour of the Apex runtime, such as specifying when a method should be called or how a variable should be serialized.

Here is an example of an Apex annotation:

@future

public static void myMethod() {

    // Code to execute in the future

}

In this example, the @future annotation tells the Apex runtime to execute the myMethod() method asynchronously at a later time.

What are Apex Governor Limits?

Apex governor limits are restrictions imposed by the Salesforce.com platform to prevent Apex code from consuming too much CPU time, heap memory, or database resources. Governor limits are designed to ensure the performance and stability of the platform and prevent runaway code from monopolizing resources.

Some common governor limits in Apex include:

CPU time limit: 10 seconds for synchronous code, and 60 seconds for asynchronous code.
Heap size limit: 6 MB for synchronous code, and 12 MB for asynchronous code.
Database query limit: 50,000 records per transaction.

Developers must be aware of these limits and write their code in a way that stays within them.

What are Apex Testing Best Practices?

Apex testing is an important part of developing robust and reliable Apex code. Here are some best practices for Apex testing:

Write test classes that cover all code paths and governor limit scenarios.
Use assertions to verify that the expected behaviour occurs.
Use test data that represent real-world scenarios.
Use the @TestSetup annotation to create test data once, rather than creating it in every test method.
Use the SeeAllData=false annotation to ensure that tests run in isolation from production data.

What are some Advanced Apex Coding Examples?

Some advanced Apex coding examples include:

Implementing complex algorithms, such as sorting, searching, and graph traversal.
Integrating with external systems, such as REST APIs or SOAP web services.
Implementing asynchronous processing using batch Apex or future methods.
Building custom user interfaces using Visualforce or Lightning components.
Extending the functionality of Salesforce.com using custom metadata or platform events.

These are just a few examples of the many advanced Apex coding scenarios that developers may encounter. To become proficient in Apex, developers must have a strong foundation in the language fundamentals and be willing to learn and experiment with new concepts and techniques.

Apex Programming Class &amp; Coding Examples