assertDoesNotThrow in JUnit - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to check that the method does not throw any exception.

JUnit

assertDoesNotThrow(() -> [1]());

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AfailTest

BthrowException

CmyMethod

DnullPointer

Attempts:

3 left

💡 Hint

Common Mistakes

Using a method that actually throws an exception.

Not using a lambda expression.

Calling the method outside the lambda.

The assertDoesNotThrow method expects a lambda that calls the method under test. Here, myMethod is the method that should not throw an exception.

2fill in blank

medium

Complete the code to assert that the lambda expression does not throw an exception.

JUnit

assertDoesNotThrow([1]);

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A() -> myMethod()

B() -> throwException()

CmyMethod()

DthrowException()

Attempts:

3 left

💡 Hint

Common Mistakes

Passing a method call directly instead of a lambda.

Using a method that throws an exception inside the lambda.

The argument to assertDoesNotThrow must be a lambda expression. Here, () -> myMethod() is the correct lambda that calls myMethod without throwing exceptions.

3fill in blank

hard

Fix the error in the assertion to correctly check no exception is thrown.

JUnit

assertDoesNotThrow(() -> [1]);

Drag options to blanks, or click blank then click option'

AmyMethod()

BmyMethod

CthrowException()

DthrowException

Attempts:

3 left

💡 Hint

Common Mistakes

Using method reference without parentheses inside the lambda.

Calling a method that throws an exception.

The lambda must call the method with parentheses to execute it. Using myMethod() calls the method inside the lambda, which is correct.

4fill in blank

hard

Fill both blanks to assert no exception is thrown when calling the method with arguments.

JUnit

assertDoesNotThrow(() -> [1]([2]));

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AprocessData

B"input"

C42

DthrowException

Attempts:

3 left

💡 Hint

Common Mistakes

Using a method that throws an exception.

Passing an argument that is not a string literal.

The lambda calls processData with the string argument "input". This checks that calling processData("input") does not throw an exception.

5fill in blank

hard

Fill all three blanks to assert no exception is thrown when calling a method with two arguments.

JUnit

assertDoesNotThrow(() -> [1]([2], [3]));

Drag options to blanks, or click blank then click option'

AcalculateSum

B5

C10

DthrowException

Attempts:

3 left

💡 Hint

Common Mistakes

Using a method that throws exceptions.

Passing arguments in the wrong order.

The lambda calls calculateSum with arguments 5 and 10. This asserts that calling calculateSum(5, 10) does not throw an exception.