Process Automation & Logic: Basic Apex 1

Question 1

What are the supported Primitive Data Types?

Answer 1

Blob
Boolean
Date
DateTime
Decimal
Double
ID
Integer
Long
Object
String
Time

Question 2

What are the supported Non-Primitive Data Types?

Answer 2

List
Set
Map
Enum
sObject
Class Object

Question 3

What is the Object Data Type?

Answer 3

An Object can be used for any data type supported in Apex as all Apex data types inherit from Object.

An Object variable that represents a more specific data type can be cast to the underlying data type.

Question 4

How can we declare a Date variable?

Answer 4

Date customDate = Date.newInstance(1939, 9, 1);

Question 5

What is the Blob data type?

Answer 5

A Blob variable is used to store a collection of binary data as a single object. The value of method of the Blob class can be used to declare a Blob variable by casting a specified string.

Question 6

What is a collection variable?

Answer 6

Collection variables are a type of variable that can be used to store multiple variables of the same data type.

Question 7

What is a List Data Type?

Answer 7

A list is an ordered, indexed (zero-based) collection of primitives or non-primitives.

Question 8

What is a SET Data Type?

Answer 8

A set is an unordered collection of unique elements and cannot contain duplicate values.

Question 9

What is a MAP Data Type?

Answer 9

A Map is a collection of key value pairs where the Keys are a set. We can declare a Map like this: Map<Integer, String> productMap = new Map<Integer, String>{8976 => ‘Laptop E15000’, 8977 => ‘Keyboard R500’, 8978 => ‘Mouse L100’};

Question 10

Can a MAP be populated directly from a SOQL query?

Answer 10

Yes, like this: Map<Id, Opportunity> oppMap = new Map<Id, Opportunity>([SELECT Id, Name, StageName FROM Opportunity]);

Question 11

What is an ENUM?

Answer 11

Enum is a data type that specifies a set of constants. Example: public enum Day { SUNDAY, MONDAY, TUESDAY, WEDNESDAY, THURSDAY, SATURDAY }

Question 12

How can we declare an sObject variable?

Answer 12

Example: sObject obj = new Account();

Question 13

An object of a class can be declared using the ______ and the new operator.

Answer 13

class name

Question 14

How do we create a variable of a class object?

Answer 14

Example: SalesOrder order = new SalesOrder(‘Laptop T1000’, 1, 126782);

Question 15

Apex is a strongly-typed language where the data type must be declared before a variable can be used. True of False?

Answer 15

True

Question 16

What is two ways we can declare Constant variables?

Answer 16

Use the Final keyword for a variable whose value should not be altered OR use the Enum Data type

Question 17

Apex enforces strict data typing where a variable is required to only accept values of the data type that is explicitly declared. True or False?

Answer 17

True

Question 18

What values are variables assigned if no value is assigned during initialization?

Answer 18

Null

Question 19

Two variables with the same name cannot exist in the same _______, or in the same “hierarchy” of blocks they are contained in.

Answer 19

scope

Question 20

The block where a variable is declared determines the scope of that variable. A variable will be available to its _______, but a variable declared in a sub-block will not be available to its parent block.

Answer 20

sub-blocks

Question 21

What is a Constant?

Answer 21

Constant is a variable whose value cannot change after it has been assigned a value.

Question 22

_______ can be defined using the final keyword on initialization, which means that the variable can be assigned at most once.

Answer 22

Constants

Question 23

An ____________ is a statement that places a value into a variable.

Answer 23

assignment statement

Question 24

What is an Expression?

Answer 24

An expression is a construct made up of variables, operators and/or method invocations, that evaluates to a single value.

Question 25

_______ can be used to join expressions with one another to create compound expressions.

Answer 25

Operators

Question 26

What is an assignment statement?

Answer 26

An assignment statement can assign a left value to a new value expression or an inline SOQL query such as: Account[] accounts =[SELECT Id, Name FROM Account WHERE BillingCity ='Rome'];

Question 27

Static variables declared in an Apex class can be directly accessed without instantiating using the following syntax:

Answer 27

ClassName.StaticVariableName

Question 28

What is the Transient keyword used for?

Answer 28

The transient keyword is used to declare variables that cannot be saved. One common usage is a field on a Visualforce page that is utilized only during the page request.

Question 29

Depending on the data types used in an assignment statement, there are cases where explicit conversion is not required. True or False?

Answer 29

True

Question 30

In general, Apex requires ___________ of one data type to another. For example, using String.format, String.valueOf, or casting a variable to String before assigning it to a String data type variable.

Answer 30

explicit conversion

Question 31

What is Implicit Conversion?

Answer 31

Lower numeric types can be assigned to higher numeric types without explicit conversion. So, directly assigning an Integer to a Decimal is allowed, but the doing the opposite will throw an error.

Question 32

In addition to numeric types, other data types can be implicitly converted such as?

Answer 32

❖A variable of ID data type can be assigned to a String. ❖Strings can be assigned to an ID, but because ID validation will execute at runtime, an exception may be thrown if the value is not a valid ID. ❖As such, the instanceOf keyword can be used to test if a string is valid ID.

Question 33

What is an Apex Method?

Answer 33

An Apex method consists of statements grouped together as a single unit in an Apex class that perform a specific business logic.

Question 34

Access modifiers such as public or protected can be added to the method definition, but it is optional. True or False?

Answer 34

True

Question 35

If a method does not return a value, the void keyword should be used instead of a return type. True or False?

Answer 35

True

Question 36

Input parameters must be separated by commas. Each parameter should be preceded by its datatype and enclosed in parentheses(). True or False?

Answer 36

True

Question 37

If there are no parameters, a set of empty parentheses() should be used. True or False?

Answer 37

True

Question 38

The static keyword can be used to define a static method, which does not require an instance of a class in order to run. True or False?

Answer 38

True

Question 39

What is the Override Keyword used for?

Answer 39

The override keyword can be used to override a method in a class that is defined as virtual or abstract.

Question 40

What is required when declaring a method in an Apex Class?

Answer 40

A Name The Data Type of the value returned Method Parameters A Body enclosed with braces

Question 41

Method Syntax Example:

Answer 41

[public | private | protected | global] [override] [static] data_type method_name (input parameters) { // body of the method}

Question 42

One must use an access modifier in the declaration of a ________ Apex class.

Answer 42

top-level

Question 43

The default access modifier is ______, which means that the method or variable can only be accessed within the Apex class in which it is defined.

Answer 43

private

Question 44

The _______ access modifier means that the method or variable can be used by any Apex in the application or namespace.

Answer 44

public

Question 45

The ________ access modifier means that the method or variable can be used by any Apex code that has access to the class and not just the Apex code in the same application.

Answer 45

global

Question 46

The ________ access modifier means that the method or variable is visible to any inner classes in the defining Apex class, and to the classes that extend the defining Apex class.

Answer 46

protected

Question 47

What is an Interface used for?

Answer 47

An interface is used to require a class to implement specific methods.

Question 48

The structure of an interface is similar to a class, but it uses the ________ keyword and only contains method signatures.

Answer 48

interface

Question 49

What does an Interfaces method signature contain?

Answer 49

A method signature does not contain a body or access modifier and only consists of the name and any method parameter or return type.

Question 50

An Apex class uses an interface by using the _________ keyword and is required to provide the body for all methods contained in the interface

Answer 50

implements

Question 51

A class can implement multiple interfaces by separating the names of the interfaces with a comma after the implements keyword. True or False?

Answer 51

True

Question 52

An interface separates the ____________ of a method from the declaration of that method.

Answer 52

implementation logic

Question 53

Batch Apex ___________ which enables it to execute complex, long-running operations over small batches of thousands of records.

Answer 53

implements an interface

Question 54

An Apex class that implements the ________________ interface is required to use batch Apex.

Answer 54

Database.Batchable

Question 55

The _________________ method can be used to execute a batch Apex job. It requires two parameters: an instance of the batch Apex class and an optional scope (number of records to pass into the method).

Answer 55

Database.executeBatch

Question 56

Batch Apex can be scheduled by implementing an interface that enables it to be scheduled as an Apex job. True or False?

Answer 56

True

Question 57

To schedule an Apex class, it must implement the __________ interface.

Answer 57

Schedulable

Question 58

The Schedule Apex page in Setup or the __________ method can be used to specify the schedule.

Answer 58

System.schedule

Question 59

A schedulable Apex class must implement the __________ method, which contains the logic that needs to be executed on a scheduled manner.

Answer 59

execute

Question 60

What is Queueable Apex?

Answer 60

Queueable Apex allows you to add asynchronous jobs to the queue and monitor them. It offers enhancements over using @future methods.

Question 61

In Queueable Apex, The ______________ method submits a job and returns a Job Id that can be used to monitor the job status.

Answer 61

System.enqueueJob()

Question 62

A Queueable class can contain non-primitive member variables such as sObjects or custom Apex classes. True or False?

Answer 62

True

Question 63

Jobs can be chained or executed sequentially by having one Queueable job enqueue the next job in its execute() method. True or False?

Answer 63

True

Question 64

Queueable jobs can be delayed by setting the delay duration in Apex Settings in Setup or via Apex code. True or False?

Answer 64

True

Question 65

A queueable class must implement the __________ and contain its processing logic in a method called execute.

Answer 65

Queueable interface

Question 66

The ______________ of Queueable jobs can be configured when calling System.enqueueJob(). It can be used to prevent runaway recursive jobs from consuming the daily async Apex limit.

Answer 66

maximum stack depth

Question 67

To ensure that only unique queueable jobs are enqueued, the __________ property can be set.

Answer 67

Duplicate Signature

Question 68

What is a Transaction Finalizer?

Answer 68

Transaction Finalizers implement an interface which enable them to attach actions to a queueable Apex job.

Question 69

The _____________ interface is used to attach an action to the asynchronous Apex job when it succeeds or fails.

Answer 69

System.Finalizer

Question 70

The System.Finalizer can only be used on asynchronous Apex jobs that use the Queueable framework. True or False?

Answer 70

True

Question 71

What is a use case of System.Finalizer Interface?

Answer 71

An ideal use case is to re-enqueue an Apex job (up to 5 times) when its operation fails.

Question 72

Finalizers can be implemented as inner classes. Alternatively, Queueable and Finalizer interfaces can be implemented in the same Apex class. True or False?

Answer 72

True

Question 73

The System.FinalizerContext interface contains four methods. True or False?

Answer 73

True

Question 74

What does the getAsyncApexJobId method do?

Answer 74

Returns the ID of the Queueable job that is attached to the finalizer

Question 75

What does the getRequestId method do?

Answer 75

Returns the request ID shared by both the finalizer execution and the Queueable job

Question 76

What does the getResult method do?

Answer 76

Returns the System.ParentJobResultenum which represents the result of the queueable job. Its value can either be SUCCESS or UNHANDLED_EXCEPTION

Question 77

What does the getException method do?

Answer 77

Returns the exception if the result of the queueable job is UNHANDLED_EXCEPTION

Question 78

What does the Comparable Interface allow?

Answer 78

Custom sort logic

Question 79

The _________________ can be used to create custom sort logic for List collections by passing an instance of the implementing class to the sort method of the List class.

Answer 79

Comparator interface