The @RepeatedTest annotation is used to write repeatable test templates that could run multiple times in JUnit. The repetition frequency can be configured as a parameter to @RepeatedTest
annotation.
1. @RepeatedTest Annotation
The @RepeatedTest annotation is used to mark a test method that should repeat a specified number of times with a configurable display name.
To repeat a test with different arguments, consider using @ParameterizedTest.
1.1. Syntax
To create a repeatable test, annotate the test method with @RepeatedTest
.
In the given example, the test method uses @RepeatedTest(5) annotation. It means that the test will be executed five times.
@DisplayName("Add operation test")
@RepeatedTest(5)
void addNumber(TestInfo testInfo) {
Calculator calculator = new Calculator();
Assertions.assertEquals(2, calculator.add(1, 1), "1 + 1 should equal 2");
}
1.2. Lifecycle Methods
Please note that each invocation of a repeated test behaves like the execution of a regular test with full support for the same lifecycle callbacks and extensions.
It means that @BeforeEach and @AfterEach annotated lifecycle methods will be invoked for each invocation of the test.
package com.howtodoinjava.junit5.examples;
import org.junit.jupiter.api.AfterAll;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.BeforeAll;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.DisplayName;
import org.junit.jupiter.api.RepeatedTest;
import org.junit.jupiter.api.RepetitionInfo;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.TestInfo;
import org.junit.platform.runner.JUnitPlatform;
import org.junit.runner.RunWith;
@RunWith(JUnitPlatform.class)
public class RepeatedTestExample {
@BeforeAll
public static void init(){
System.out.println("Before All init() method called");
}
@BeforeEach
public void initEach(){
System.out.println("Before Each initEach() method called");
}
@DisplayName("Add operation test")
@RepeatedTest(5)
void addNumber(TestInfo testInfo, RepetitionInfo repetitionInfo)
{
System.out.println("Running addNumber test -> " + repetitionInfo.getCurrentRepetition());
Assertions.assertEquals(2, Calculator.add(1, 1), "1 + 1 should equal 2");
}
@AfterEach
public void cleanUpEach(){
System.out.println("After Each cleanUpEach() method called");
}
@AfterAll
public static void cleanUp(){
System.out.println("After All cleanUp() method called");
}
}
The output of the above test:
Before All init() method called
Before Each initEach() method called
After Each cleanUpEach() method called
Before Each initEach() method called
Running addNumber test -> 1
After Each cleanUpEach() method called
Before Each initEach() method called
Running addNumber test -> 2
After Each cleanUpEach() method called
Before Each initEach() method called
Running addNumber test -> 3
After Each cleanUpEach() method called
Before Each initEach() method called
Running addNumber test -> 4
After Each cleanUpEach() method called
Before Each initEach() method called
Running addNumber test -> 5
After Each cleanUpEach() method called
After All cleanUp() method called
2. Custom Display Names
Apart from specifying the number of repetitions, we can give a custom display name to each repetition. This custom display name can be a combination of {static text + dynamic placeholders}.
Currently, three placeholders are supported:
{displayName}
: display name of the@RepeatedTest
method.{currentRepetition}
: the current repetition count.{totalRepetitions}
: the total number of repetitions.
public class JUnit5AnnotationsExample
{
@DisplayName("Add operation test")
@RepeatedTest(value = 5, name = "{displayName} - repetition {currentRepetition} of {totalRepetitions}")
void addNumber(TestInfo testInfo) {
Assertions.assertEquals(2, Calculator.add(1, 1), "1 + 1 should equal 2");
}
}
Running the above test will output in below:

We can use one of two predefined formats i.e. LONG_DISPLAY_NAME
and SHORT_DISPLAY_NAME
. The latter is the default format if none is specified.
RepeatedTest.LONG_DISPLAY_NAME
– {displayName} :: repetition {currentRepetition} of {totalRepetitions}RepeatedTest.SHORT_DISPLAY_NAME
– repetition {currentRepetition} of {totalRepetitions}
@DisplayName("Add operation test")
@RepeatedTest(value = 5, name = RepeatedTest.LONG_DISPLAY_NAME)
void addNumber(TestInfo testInfo) {
Assertions.assertEquals(2, Calculator .add(1, 1), "1 + 1 should equal 2");
}
3. RepetitionInfo interface
RepetitionInfo is used to fetch information about the current repetition of a repeated test inside the @RepeatedTest
, or lifecycle methods such as @BeforeEach
, and @AfterEach
.
public class JUnit5AnnotationsExample {
@BeforeEach
public void initEach(RepetitionInfo info){
int currentRepetition = info.getCurrentRepetition();
int totalRepetitions = info.getTotalRepetitions();
//Use information as needed
}
@DisplayName("Add operation test")
@RepeatedTest(value = 5, name="{displayName} :: repetition {currentRepetition} of {totalRepetitions}")
void addNumber(TestInfo testInfo) {
Calculator calculator = new Calculator();
Assertions.assertEquals(2, calculator.add(1, 1), "1 + 1 should equal 2");
}
@AfterEach
public void cleanUpEach(RepetitionInfo info){
int currentRepetition = info.getCurrentRepetition();
int totalRepetitions = info.getTotalRepetitions();
//Use information as needed
}
}
Happy Learning !!
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