Add JUnit 5 @RepeatedTest demo project

Initial commit of a Maven project demonstrating JUnit 5's @RepeatedTest annotation. Includes example tests for basic repetition, custom display names, metadata injection, lifecycle management, and failure thresholds. Project files include .gitignore, README, pom.xml, and test classes under src/test/java/com/ankurm/tutorials/junit/repeated.

.gitignore

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+# Compiled class file
+*.class
+
+# Log file
+*.log
+
+# BlueJ files
+*.ctxt
+
+# Mobile Tools for Java (J2ME)
+.mtj.tmp/
+
+# Package Files #
+*.jar
+*.war
+*.nar
+*.ear
+*.zip
+*.tar.gz
+*.rar
+
+# virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
+hs_err_pid*
+replay_pid*
+
+#IntelliJ IDEA
+.idea/

RepeatedTest/README.md

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+# JUnit 5 @RepeatedTest Demonstration
+
+This project demonstrates the usage of JUnit 5's `@RepeatedTest` annotation to improve test reliability and handle flaky tests.
+
+## Concepts Covered
+
+The code examples in `src/test/java/com/ankurTutorials/junit/repeated` cover the following concepts:
+
+1.  **Basic Repetition**: Repeating a test a specific number of times.
+    - File: `ReliabilityTest.java`
+2.  **Custom Display Names**: Configuring formatted names for each repetition for better reporting in CI/CD.
+    - File: `CustomNameTest.java`
+3.  **Metadata Injection**: Using `RepetitionInfo` to access the current repetition index and total count within the test.
+    - File: `MetadataTest.java`
+4.  **Lifecycle Management**: Understanding how `@BeforeEach` and `@AfterEach` interact with repeated tests (they run for *each* repetition).
+    - File: `LifecycleTest.java`
+5.  **Failure Thresholds**: Using the `failureThreshold` attribute (JUnit 5.10+) to stop execution early if a certain number of failures occur.
+    - File: `FlakyServiceTest.java`
+
+## Prerequisites
+
+- Java 17 or higher
+- Maven 3.6+
+
+## How to Run
+
+To run all tests, execute the following command in the project root:
+
+```bash
+mvn test
+```
+
+To run a specific test class:
+
+```bash
+mvn -Dtest=BasicUsageTest test
+```

RepeatedTest/pom.xml

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+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0"
+         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+    <modelVersion>4.0.0</modelVersion>
+
+    <groupId>com.ankurTutorials</groupId>
+    <artifactId>repeated-test-demo</artifactId>
+    <version>1.0-SNAPSHOT</version>
+
+    <properties>
+        <maven.compiler.source>17</maven.compiler.source>
+        <maven.compiler.target>17</maven.compiler.target>
+        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
+        <junit.version>5.10.1</junit.version>
+    </properties>
+
+    <dependencies>
+        <dependency>
+            <groupId>org.junit.jupiter</groupId>
+            <artifactId>junit-jupiter</artifactId>
+            <version>${junit.version}</version>
+            <scope>test</scope>
+        </dependency>
+    </dependencies>
+
+    <build>
+        <plugins>
+            <plugin>
+                <groupId>org.apache.maven.plugins</groupId>
+                <artifactId>maven-surefire-plugin</artifactId>
+                <version>3.2.3</version>
+            </plugin>
+        </plugins>
+    </build>
+</project>

RepeatedTest/src/test/java/com/ankurm/tutorials/junit/repeated/CustomNameTest.java

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+package com.ankurm.tutorials.junit.repeated;
+
+import org.junit.jupiter.api.DisplayName;
+import org.junit.jupiter.api.RepeatedTest;
+
+public class CustomNameTest {
+
+    @RepeatedTest(value = 3, name = "{displayName} - Run {currentRepetition}/{totalRepetitions}")
+    @DisplayName("Critical API Integration")
+    void customNameTest() {
+        System.out.println("Verifying external API stability...");
+        // Logic to verify external API stability
+    }
+}

RepeatedTest/src/test/java/com/ankurm/tutorials/junit/repeated/FlakyServiceTest.java

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+package com.ankurm.tutorials.junit.repeated;
+
+import org.junit.jupiter.api.RepeatedTest;
+import static org.junit.jupiter.api.Assertions.fail;
+
+public class FlakyServiceTest {
+
+    // If 2 out of the 10 repetitions fail, JUnit stops further executions.
+    // Note: failureThreshold requires JUnit 5.10+
+    @RepeatedTest(value = 10, failureThreshold = 2)
+    void flakyServiceTest() {
+        // Simulating intermittent failure (mostly passing)
+        // Using a high failure rate here to demonstrate the threshold quickly if run multiple times
+        // or effectively showing it passes mostly.
+        // Let's make it 30% failure chance.
+        if (Math.random() < 0.3) {
+            fail("Simulated random failure");
+        }
+        System.out.println("Test passed");
+    }
+}

RepeatedTest/src/test/java/com/ankurm/tutorials/junit/repeated/LifecycleTest.java

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+package com.ankurm.tutorials.junit.repeated;
+
+import org.junit.jupiter.api.AfterEach;
+import org.junit.jupiter.api.BeforeEach;
+import org.junit.jupiter.api.RepeatedTest;
+import org.junit.jupiter.api.RepetitionInfo;
+
+public class LifecycleTest {
+
+    @BeforeEach
+    void setUp(RepetitionInfo info) {
+        System.out.println("BeforeEach: Setting up for repetition " + info.getCurrentRepetition());
+    }
+
+    @RepeatedTest(3)
+    void lifecycleTest() {
+        System.out.println("Executing test logic...");
+    }
+
+    @AfterEach
+    void tearDown(RepetitionInfo info) {
+        System.out.println("AfterEach: Cleaning up after repetition " + info.getCurrentRepetition());
+    }
+}

RepeatedTest/src/test/java/com/ankurm/tutorials/junit/repeated/MetadataTest.java

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+package com.ankurm.tutorials.junit.repeated;
+
+import org.junit.jupiter.api.RepeatedTest;
+import org.junit.jupiter.api.RepetitionInfo;
+
+class MetadataTest {
+
+    @RepeatedTest(3)
+    void testWithMetadata(RepetitionInfo info) {
+        int current = info.getCurrentRepetition();
+        int total = info.getTotalRepetitions();
+        
+        // Log progress or vary data inputs based on 'current'
+        System.out.println("Processing batch: " + current + " of " + total);
+    }
+}

RepeatedTest/src/test/java/com/ankurm/tutorials/junit/repeated/ReliabilityTest.java

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+package com.ankurm.tutorials.junit.repeated;
+
+import org.junit.jupiter.api.RepeatedTest;
+import static org.junit.jupiter.api.Assertions.assertTrue;
+
+public class ReliabilityTest {
+
+    @RepeatedTest(5) // The test will run exactly 5 times
+    void simpleRepeatTest() {
+        System.out.println("Executing test...");
+        assertTrue(true);
+    }
+}