Based on this code, what is the value of %?

A developer considers the following snippet of code:

Boolean isOK;

integer x;

String theString = ‘Hello’;

if (isOK == false && theString == ‘Hello’) {

x = 1;

} else if (isOK == true && theString ==’Hello’) {

x = 2;

} else if (isOK != null && theString == ‘Hello’) {

x = 3;

} else {

x = 4;

}

Based on this code, what is the value of %?
A . 1
B . 3
C . 4
D . 2

View Answer

Answer: B

Explanation:

In the provided code snippet:

Boolean isOK;

Integer x;

String theString = ‘Hello’;

if (isOK == false && theString == ‘Hello’) {

x = 1;

} else if (isOK == true && theString == ‘Hello’) {

x = 2;

} else if (isOK != null && theString == ‘Hello’) {

x = 3; } else {

x = 4;

}

Variable Initialization:

Boolean isOK; → Declared but not initialized, so isOK is null.

Integer x; → Declared but not initialized.

String theString = ‘Hello’; → Initialized to ‘Hello’.

Evaluation of Conditions:

First Condition:

if (isOK == false && theString == ‘Hello’)

isOK == false → Since isOK is null, this evaluates to false.

Overall condition: false && true → false.

Second Condition:

else if (isOK == true && theString == ‘Hello’)

isOK == true → Since isOK is null, this evaluates to false.

Overall condition: false && true → false.

Third Condition:

else if (isOK != null && theString == ‘Hello’)

isOK != null → Since isOK is null, this evaluates to false.

Overall condition: false && true → false.

Else Block:

else {

x = 4;

}

Since none of the previous conditions are met, the else block is executed.

x is assigned the value 4.

Conclusion:

The variable x is assigned the value 4.

Reference: Variable Initialization:

"Instance variables are initialized to null. Local variables are not initialized, so their value is undefined until you assign a value."

― Apex Developer Guide: Variables Conditional Statements and Null Values:

"In Apex, comparisons with null are straightforward. If you compare null to a value, the result is false."

― Apex Developer Guide: Expressions