Controlling Program Flow →easyMultiple ChoiceObjective-mapped

1Z0-829 Controlling Program Flow Practice Question

Exhibit

Refer to the exhibit.

```
Error: incompatible types: bad type in switch expression
        return switch(day) {
                     ^
  required: int
  found:    String
```

What is the likely cause of this compilation error? ```java String day = "Monday";

int dayNum = switch (day) {

case 1 -> 1; case 2 -> 2; default -> 0;

};

System.out.println(dayNum); ```

⚠ Common exam trap

The trap here is that candidates often overlook the type compatibility requirement and focus on syntax details like arrow syntax or missing default, assuming the error is about completeness or assignment rather than a fundamental type mismatch.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

The switch selector is a String but case labels are int constants.

In a Java switch expression, the selector type and case label types must be compatible. If the selector is a String, the case labels must be String constants; int constants would cause a compilation error due to type mismatch. Options A, B, and C describe syntax issues that are not the primary cause here.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
The switch expression uses arrow syntax but the keys are not unique.
Why it's wrong here
Duplicate case labels would be a different error.
✗
The switch expression is missing a default case.
Why it's wrong here
Missing default gives a different error about not all values covered.
✗
The switch expression is not assigned to a variable.
Why it's wrong here
Switch expression must be assigned or used; but missing assignment gives a different error.
✓
The switch selector is a String but case labels are int constants.
Why this is correct
Switch expression requires consistent types; likely String selector with int cases.

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1Z0-829 Controlling Program Flow Practice Question

Exhibit

Why each option matters

Option-by-option breakdown

Related to this question