Book Image

Mastering Apex Programming

By : Paul Battisson
5 (1)
Book Image

Mastering Apex Programming

5 (1)
By: Paul Battisson

Overview of this book

As applications built on the Salesforce platform are now a key part of many organizations, developers are shifting focus to Apex, Salesforce’s proprietary programming language. As a Salesforce developer, it is important to understand the range of tools at your disposal, how and when to use them, and best practices for working with Apex. Mastering Apex Programming will help you explore the advanced features of Apex programming and guide you in delivering robust solutions that scale. This book starts by taking you through common Apex mistakes, debugging, exception handling, and testing. You'll then discover different asynchronous Apex programming options and develop custom Apex REST web services. The book shows you how to define and utilize Batch Apex, Queueable Apex, and Scheduled Apex using common scenarios before teaching you how to define, publish, and consume platform events and RESTful endpoints with Apex. Finally, you'll learn how to profile and improve the performance of your Apex application, including architecture trade-offs. With code examples used to facilitate discussion throughout, by the end of the book, you'll have developed the skills needed to build robust and scalable applications in Apex.
Table of Contents (21 chapters)
1
Section 1 – Triggers, Testing, and Security
8
Section 2 – Asynchronous Apex and Apex REST
15
Section 3 – Apex Performance

Catching errors

The first step in correctly managing any exception is to begin by catching it correctly. Apex allows developers to do this using the try-catch-finally syntax, shown as follows:

try {
	//Run some code
} catch(ExceptionType ex) {
	//Handle the exception appropriately
} finally {
	//Perform some final clean up code
}

A try statement must have a catch or finally block associated with it in order for the code to compile correctly.

In the catch statement, we can specify a type of exception that we want to handle, for example:

try {
	Account acc = null;
	acc.Name = 'Test'; //This will throw a                        //NullPointerException - see Chapter 1
} catch(NullPointerException ex) {
	//Handle the exception
}

Note that if in this code we had a QueryException thrown instead of a NullPointerException, the catch block would not have caught...