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How to use Parameterized class of org.junit.runners package

Best junit code snippet using org.junit.runners.Parameterized

Source:BlockJUnit4ClassRunnerWithParameters.java

...3import java.lang.reflect.Field;4import java.util.List;5import org.junit.runner.notification.RunNotifier;6import org.junit.runners.BlockJUnit4ClassRunner;7import org.junit.runners.Parameterized;8import org.junit.runners.model.FrameworkField;9import org.junit.runners.model.FrameworkMethod;10import org.junit.runners.model.InitializationError;11import org.junit.runners.model.Statement;12public class BlockJUnit4ClassRunnerWithParameters extends BlockJUnit4ClassRunner {13    private final String name;14    private final Object[] parameters;15    public BlockJUnit4ClassRunnerWithParameters(TestWithParameters test) throws InitializationError {16        super(test.getTestClass().getJavaClass());17        this.parameters = test.getParameters().toArray(new Object[test.getParameters().size()]);18        this.name = test.getName();19    }20    @Override // org.junit.runners.BlockJUnit4ClassRunner21    public Object createTest() throws Exception {22        if (fieldsAreAnnotated()) {23            return createTestUsingFieldInjection();24        }25        return createTestUsingConstructorInjection();26    }27    private Object createTestUsingConstructorInjection() throws Exception {28        return getTestClass().getOnlyConstructor().newInstance(this.parameters);29    }30    private Object createTestUsingFieldInjection() throws Exception {31        List<FrameworkField> annotatedFieldsByParameter = getAnnotatedFieldsByParameter();32        if (annotatedFieldsByParameter.size() == this.parameters.length) {33            Object testClassInstance = getTestClass().getJavaClass().newInstance();34            for (FrameworkField each : annotatedFieldsByParameter) {35                Field field = each.getField();36                int index = ((Parameterized.Parameter) field.getAnnotation(Parameterized.Parameter.class)).value();37                try {38                    field.set(testClassInstance, this.parameters[index]);39                } catch (IllegalArgumentException iare) {40                    throw new Exception(getTestClass().getName() + ": Trying to set " + field.getName() + " with the value " + this.parameters[index] + " that is not the right type (" + this.parameters[index].getClass().getSimpleName() + " instead of " + field.getType().getSimpleName() + ").", iare);41                }42            }43            return testClassInstance;44        }45        throw new Exception("Wrong number of parameters and @Parameter fields. @Parameter fields counted: " + annotatedFieldsByParameter.size() + ", available parameters: " + this.parameters.length + ".");46    }47    /* access modifiers changed from: protected */48    @Override // org.junit.runners.ParentRunner49    public String getName() {50        return this.name;51    }52    /* access modifiers changed from: protected */53    @Override // org.junit.runners.BlockJUnit4ClassRunner54    public String testName(FrameworkMethod method) {55        return method.getName() + getName();56    }57    /* access modifiers changed from: protected */58    @Override // org.junit.runners.BlockJUnit4ClassRunner59    public void validateConstructor(List<Throwable> errors) {60        validateOnlyOneConstructor(errors);61        if (fieldsAreAnnotated()) {62            validateZeroArgConstructor(errors);63        }64    }65    /* access modifiers changed from: protected */66    @Override // org.junit.runners.BlockJUnit4ClassRunner67    public void validateFields(List<Throwable> errors) {68        super.validateFields(errors);69        if (fieldsAreAnnotated()) {70            List<FrameworkField> annotatedFieldsByParameter = getAnnotatedFieldsByParameter();71            int[] usedIndices = new int[annotatedFieldsByParameter.size()];72            for (FrameworkField each : annotatedFieldsByParameter) {73                int index = ((Parameterized.Parameter) each.getField().getAnnotation(Parameterized.Parameter.class)).value();74                if (index < 0 || index > annotatedFieldsByParameter.size() - 1) {75                    errors.add(new Exception("Invalid @Parameter value: " + index + ". @Parameter fields counted: " + annotatedFieldsByParameter.size() + ". Please use an index between 0 and " + (annotatedFieldsByParameter.size() - 1) + "."));76                } else {77                    usedIndices[index] = usedIndices[index] + 1;78                }79            }80            for (int index2 = 0; index2 < usedIndices.length; index2++) {81                int numberOfUse = usedIndices[index2];82                if (numberOfUse == 0) {83                    errors.add(new Exception("@Parameter(" + index2 + ") is never used."));84                } else if (numberOfUse > 1) {85                    errors.add(new Exception("@Parameter(" + index2 + ") is used more than once (" + numberOfUse + ")."));86                }87            }88        }89    }90    /* access modifiers changed from: protected */91    @Override // org.junit.runners.ParentRunner92    public Statement classBlock(RunNotifier notifier) {93        return childrenInvoker(notifier);94    }95    /* access modifiers changed from: protected */96    @Override // org.junit.runners.ParentRunner97    public Annotation[] getRunnerAnnotations() {98        return new Annotation[0];99    }100    private List<FrameworkField> getAnnotatedFieldsByParameter() {101        return getTestClass().getAnnotatedFields(Parameterized.Parameter.class);102    }103    private boolean fieldsAreAnnotated() {104        return !getAnnotatedFieldsByParameter().isEmpty();105    }106}...

Source:AbstractParameterizedHazelcastClassRunner.java

...15 */16package com.hazelcast.test;17import org.junit.runner.notification.RunNotifier;18import org.junit.runners.BlockJUnit4ClassRunner;19import org.junit.runners.Parameterized;20import org.junit.runners.model.FrameworkField;21import org.junit.runners.model.FrameworkMethod;22import org.junit.runners.model.InitializationError;23import org.junit.runners.model.Statement;24import java.lang.annotation.Annotation;25import java.lang.reflect.Field;26import java.util.List;27/**28 * A base test runner which has an ability to run parameterized tests.29 */30public abstract class AbstractParameterizedHazelcastClassRunner extends BlockJUnit4ClassRunner {31    protected boolean isParameterized;32    protected Object[] fParameters;33    protected String fName;34    /**35     * Creates a BlockJUnit4ClassRunner to run {@code clazz}36     *37     * @throws org.junit.runners.model.InitializationError if the test class is malformed.38     */39    public AbstractParameterizedHazelcastClassRunner(Class<?> clazz) throws InitializationError {40        super(clazz);41    }42    public AbstractParameterizedHazelcastClassRunner(Class<?> clazz, Object[] parameters, String name)43            throws InitializationError {44        super(clazz);45        fParameters = parameters;46        fName = name;47        isParameterized = true;48    }49    @Override50    protected String getName() {51        if (isParameterized) {52            return fName;53        } else {54            return super.getName();55        }56    }57    @Override58    protected String testName(FrameworkMethod method) {59        if (isParameterized) {60            return method.getName() + getName();61        } else {62            return method.getName();63        }64    }65    public void setParameterized(boolean isParameterized) {66        this.isParameterized = isParameterized;67    }68    @Override69    public Object createTest() throws Exception {70        if (isParameterized) {71            if (fieldsAreAnnotated()) {72                return createTestUsingFieldInjection();73            } else {74                return createTestUsingConstructorInjection();75            }76        }77        return super.createTest();78    }79    private Object createTestUsingConstructorInjection() throws Exception {80        return getTestClass().getOnlyConstructor().newInstance(fParameters);81    }82    @Override83    protected void validateConstructor(List<Throwable> errors) {84        validateOnlyOneConstructor(errors);85        if (fieldsAreAnnotated()) {86            validateZeroArgConstructor(errors);87        }88    }89    private Object createTestUsingFieldInjection() throws Exception {90        List<FrameworkField> annotatedFieldsByParameter = getAnnotatedFieldsByParameter();91        if (annotatedFieldsByParameter.size() != fParameters.length) {92            throw new Exception("Wrong number of parameters and @Parameter fields."93                    + " @Parameter fields counted: " + annotatedFieldsByParameter.size()94                    + ", available parameters: " + fParameters.length + ".");95        }96        Object testClassInstance = getTestClass().getJavaClass().newInstance();97        for (FrameworkField each : annotatedFieldsByParameter) {98            Field field = each.getField();99            Parameterized.Parameter annotation = field.getAnnotation(Parameterized.Parameter.class);100            int index = annotation.value();101            try {102                field.set(testClassInstance, fParameters[index]);103            } catch (IllegalArgumentException iare) {104                throw new Exception(getTestClass().getName() + ": Trying to set " + field.getName()105                        + " with the value " + fParameters[index]106                        + " that is not the right type (" + fParameters[index].getClass().getSimpleName() + " instead of "107                        + field.getType().getSimpleName() + ").", iare);108            }109        }110        return testClassInstance;111    }112    private boolean fieldsAreAnnotated() {113        return !getAnnotatedFieldsByParameter().isEmpty();114    }115    private List<FrameworkField> getAnnotatedFieldsByParameter() {116        return getTestClass().getAnnotatedFields(Parameterized.Parameter.class);117    }118    @Override119    protected Statement classBlock(RunNotifier notifier) {120        if (isParameterized) {121            return childrenInvoker(notifier);122        } else {123            return super.classBlock(notifier);124        }125    }126    @Override127    protected Annotation[] getRunnerAnnotations() {128        return new Annotation[0];129    }130}...

Source:ClassificationRunnerWithParameters.java

...17import org.eclipse.papyrus.junit.framework.classification.rules.Conditional;18import org.junit.rules.TestRule;19import org.junit.runner.Description;20import org.junit.runner.notification.RunNotifier;21import org.junit.runners.Parameterized;22import org.junit.runners.Parameterized.Parameters;23import org.junit.runners.Parameterized.UseParametersRunnerFactory;24import org.junit.runners.model.FrameworkMethod;25import org.junit.runners.model.InitializationError;26import org.junit.runners.model.Statement;27import org.junit.runners.parameterized.BlockJUnit4ClassRunnerWithParameters;28import org.junit.runners.parameterized.TestWithParameters;29/**30 * A Test Runner which is aware of Classification-related annotations and {@link Conditional @Conditional} tests,31 * for use with test {@link Parameters}.32 *33 * It ignores the test methods according to their annotations, and the policy defined34 * in {@link ClassificationConfig}.35 *36 * @see Parameterized37 * @see UseParametersRunnerFactory38 * @see ClassificationRunnerWithParametersFactory39 * @see ClassificationConfig40 * @see TestCategory41 * @see Conditional42 *43 */44public class ClassificationRunnerWithParameters extends BlockJUnit4ClassRunnerWithParameters {45	private final ClassificationRunnerImpl impl;46	public ClassificationRunnerWithParameters(TestWithParameters test) throws InitializationError {47		super(test);48		this.impl = new ClassificationRunnerImpl(new ClassificationRunnerImpl.Delegate() {49			@Override50			public void runChild(FrameworkMethod method, RunNotifier notifier) {...

Source:ParametersButNotParameterizedTest.java

...18import com.google.errorprone.CompilationTestHelper;19import org.junit.Test;20import org.junit.runner.RunWith;21import org.junit.runners.JUnit4;22/** Tests for {@link ParametersButNotParameterized}. */23@RunWith(JUnit4.class)24public final class ParametersButNotParameterizedTest {25  private final CompilationTestHelper helper =26      CompilationTestHelper.newInstance(ParametersButNotParameterized.class, getClass());27  private final BugCheckerRefactoringTestHelper refactoringHelper =28      BugCheckerRefactoringTestHelper.newInstance(ParametersButNotParameterized.class, getClass());29  @Test30  public void positive() {31    refactoringHelper32        .addInputLines(33            "Test.java",34            "import org.junit.runner.RunWith;",35            "import org.junit.runners.JUnit4;",36            "import org.junit.runners.Parameterized.Parameter;",37            "@RunWith(JUnit4.class)",38            "public class Test {",39            "  @Parameter public int foo;",40            "}")41        .addOutputLines(42            "Test.java",43            "import org.junit.runner.RunWith;",44            "import org.junit.runners.JUnit4;",45            "import org.junit.runners.Parameterized;",46            "import org.junit.runners.Parameterized.Parameter;",47            "@RunWith(Parameterized.class)",48            "public class Test {",49            "  @Parameter public int foo;",50            "}")51        .doTest();52  }53  @Test54  public void alreadyParameterized_noFinding() {55    helper56        .addSourceLines(57            "Test.java",58            "import org.junit.runner.RunWith;",59            "import org.junit.runners.Parameterized;",60            "import org.junit.runners.Parameterized.Parameter;",61            "@RunWith(Parameterized.class)",62            "public class Test {",63            "  @Parameter public int foo;",64            "}")65        .doTest();66  }67  @Test68  public void noParameters_noFinding() {69    helper70        .addSourceLines(71            "Test.java",72            "import org.junit.runner.RunWith;",73            "import org.junit.runners.JUnit4;",74            "@RunWith(JUnit4.class)",75            "public class Test {",...

Source:PracUseParametersRunnerFactory.java

1package junit4.v4_12;2import org.junit.Test;3import org.junit.runner.RunWith;4import org.junit.runner.Runner;5import org.junit.runners.Parameterized;6import org.junit.runners.Parameterized.Parameter;7import org.junit.runners.Parameterized.Parameters;8import org.junit.runners.Parameterized.UseParametersRunnerFactory;9import org.junit.runners.model.InitializationError;10import org.junit.runners.parameterized.BlockJUnit4ClassRunnerWithParameters;11import org.junit.runners.parameterized.ParametersRunnerFactory;12import org.junit.runners.parameterized.TestWithParameters;13import java.util.Arrays;14import java.util.List;15/**16 * {@link UseParametersRunnerFactory} ãç¡çç¢çä½¿ã£ã¦ã¿ãã17 *18 * @author irof19 */20@RunWith(Parameterized.class)21@UseParametersRunnerFactory(PracUseParametersRunnerFactory.FriendlyRunner.Factory.class)22public class PracUseParametersRunnerFactory {23    /**24     * ãã©ã¡ã¼ã¿ãä¸ã¤ã®æã¯åç´ãªãªã¹ãã® <code>@parameters</code> ã¨25     * åä¸ã® <code>@Parameter</code> ãã£ã¼ã«ãã§è¯ããªã£ãã26     */27    @Parameters28    public static List<String> data() {29        return Arrays.asList("A", "B", "C");30    }31    @Parameter32    public String arg;33    @Test34    public void test() throws Exception {...

Source:IsolatedParametersRunnerFactory.java

...17import org.junit.runners.parameterized.ParametersRunnerFactory;18import org.junit.runners.parameterized.TestWithParameters;19/**20 * {@link ParametersRunnerFactory} for21 * {@link org.junit.runners.Parameterized.UseParametersRunnerFactory UseParametersRunnerFactory} annotation22 * to run tests with parameters in a separate ClassLoader.23 *24 * @see Isolated25 */26public class IsolatedParametersRunnerFactory implements ParametersRunnerFactory {27    @Override28    public Runner createRunnerForTestWithParameters(TestWithParameters test) throws InitializationError {29        return new IsolatedParameterizedRunner(test);30    }31    private static class IsolatedParameterizedRunner extends BlockJUnit4ClassRunnerWithParameters {32        public IsolatedParameterizedRunner(TestWithParameters test) throws InitializationError {33            super(isolated(test));34        }35        private static TestWithParameters isolated(TestWithParameters test) throws InitializationError {36            Class<?> testClass = test.getTestClass().getJavaClass();37            Class<?> isolatedTestClass = IsolatedClassLoader.isolatedTestClass(testClass);38            return new TestWithParameters(test.getName(), new TestClass(isolatedTestClass), test.getParameters());39        }40    }41}...

Source:ClassificationRunnerWithParametersFactory.java

...14 *****************************************************************************/15package org.eclipse.papyrus.junit.framework.classification;16import org.junit.runner.RunWith;17import org.junit.runner.Runner;18import org.junit.runners.Parameterized;19import org.junit.runners.Parameterized.UseParametersRunnerFactory;20import org.junit.runners.model.InitializationError;21import org.junit.runners.parameterized.ParametersRunnerFactory;22import org.junit.runners.parameterized.TestWithParameters;23/**24 * Factory for classification-sensitive parameterized test suites.25 * Specify this factory in the {@literal @}{@link UseParametersRunnerFactory}26 * annotation on your <tt>{@literal @}{@link RunWith}({@link Parameterized}.class)</tt>27 * test class to support the classfication and condition annotations of the Papyrus28 * test framework.29 * 30 * @see Parameterized31 * @see UseParametersRunnerFactory32 * @since 1.233 */34public class ClassificationRunnerWithParametersFactory implements ParametersRunnerFactory {35	public ClassificationRunnerWithParametersFactory() {36		super();37	}38	@Override39	public Runner createRunnerForTestWithParameters(TestWithParameters test) throws InitializationError {40		return new ClassificationRunnerWithParameters(test);41	}42}...

Source:AllRunnersTests.java

2import org.junit.runner.RunWith;3import org.junit.runners.Suite;4import org.junit.runners.Suite.SuiteClasses;5import org.junit.runners.model.AllModelTests;6import org.junit.runners.parameterized.AllParameterizedTests;7@RunWith(Suite.class)8@SuiteClasses({9        AllModelTests.class,10        AllParameterizedTests.class,11        RuleContainerTest.class,12        CustomBlockJUnit4ClassRunnerTest.class13})14public class AllRunnersTests {15}...

Parameterized

Using AI Code Generation

1import static org.junit.Assert.assertEquals;2import java.util.Arrays;3import java.util.Collection;4import org.junit.Test;5import org.junit.runner.RunWith;6import org.junit.runners.Parameterized;7import org.junit.runners.Parameterized.Parameters;8@RunWith(Parameterized.class)9public class TestParameterized {10	private int input;11	private int expected;12	public TestParameterized(int input, int expected) {13		this.input = input;14		this.expected = expected;15	}16	public static Collection<Object[]> data() {17		Object[][] data = new Object[][] {{1,2}, {5,6}, {121,122}};18		return Arrays.asList(data);19	}20	public void test() {21		assertEquals(expected, new MyClass().addOne(input));22	}23}24class MyClass {25	public int addOne(int x) {26		return x+1;27	}28}

Parameterized

Using AI Code Generation

1package com.journaldev.junit;2import org.junit.Test;3import org.junit.runner.RunWith;4import org.junit.runners.Parameterized;5import org.junit.runners.Parameterized.Parameters;6import java.util.Arrays;7import java.util.Collection;8import static org.junit.Assert.assertEquals;9@RunWith(Parameterized.class)10public class TestParameterized {11    private int number1;12    private int number2;13    private int expected;14    public TestParameterized(int number1, int number2, int expected) {15        this.number1 = number1;16        this.number2 = number2;17        this.expected = expected;18    }19    public static Collection<Object[]> data() {20        Object[][] data = new Object[][] { { 1, 2, 3 }, { 5, 3, 8 }, { 121, 4, 125 }, { 11, 9, 20 } };21        return Arrays.asList(data);22    }23    public void testAdd() {24        assertEquals(expected, new Calculator().add(number1, number2));25    }26}

Parameterized

Using AI Code Generation

1import org.junit.Test;2import org.junit.runner.RunWith;3import org.junit.runners.Parameterized;4import org.junit.runners.Parameterized.Parameters;5import java.util.Arrays;6import java.util.Collection;7@RunWith(Parameterized.class)8public class TestWithParameters {9    private int number;10    public TestWithParameters(int number) {11        this.number = number;12    }13    public static Collection<Object[]> data() {14        Object[][] data = new Object[][] { { 1 }, { 2 }, { 3 }, { 4 } };15        return Arrays.asList(data);16    }17    public void test() {18        System.out.println("Parameterized Number is : " + number);19    }20}

Parameterized

Using AI Code Generation

1@RunWith(Parameterized.class)2public class TestClass {3    private int input;4    private int expected;5    public TestClass(int input, int expected) {6        this.input = input;7        this.expected = expected;8    }9    public static Collection<Object[]> data() {10        return Arrays.asList(new Object[][] {11                { 1, 2 },12                { 2, 4 },13                { 8, 16 }14        });15    }16    public void test() {17        assertEquals(expected, new MyClass().doubleTheNumber(input));18    }19}20public class MyClass {21    public int doubleTheNumber(int number) {22        return number * 2;23    }24}25OK (1 test)

Parameterized

Using AI Code Generation

1@RunWith(Parameterized.class)2public class TestParameterized {3    private int number;4    public TestParameterized(int number) {5        this.number = number;6    }7    public static Collection<Object[]> data() {8        Object[][] data = new Object[][] { { 1 }, { 2 }, { 3 }, { 4 }, { 5 } };9        return Arrays.asList(data);10    }11    public void test() {12        assertTrue(number > 0 && number < 6);13    }14}

Parameterized

Using AI Code Generation

1@RunWith(Parameterized.class)2public class TestParameterized {3	private String expected;4	private String actual;5	public TestParameterized(String expected, String actual) {6		this.expected = expected;7		this.actual = actual;8	}9	public static Collection<String[]> getTestParameters() {10		return Arrays.asList(new String[][] {11			{"Hello", "Hello"},12			{"World", "World"}13		});14	}15	public void test() {16		assertEquals(expected, actual);17	}18}

JUnit Tutorial:

LambdaTest also has a detailed JUnit tutorial explaining its features, importance, advanced use cases, best practices, and more to help you get started with running your automation testing scripts.

JUnit Tutorial Chapters:

Here are the detailed JUnit testing chapters to help you get started:

Importance of Unit testing - Learn why Unit testing is essential during the development phase to identify bugs and errors.
Top Java Unit testing frameworks - Here are the upcoming JUnit automation testing frameworks that you can use in 2023 to boost your unit testing.
What is the JUnit framework
Why is JUnit testing important - Learn the importance and numerous benefits of using the JUnit testing framework.
Features of JUnit - Learn about the numerous features of JUnit and why developers prefer it.
JUnit 5 vs. JUnit 4: Differences - Here is a complete comparison between JUnit 5 and JUnit 4 testing frameworks.
Setting up the JUnit environment - Learn how to set up your JUnit testing environment.
Getting started with JUnit testing - After successfully setting up your JUnit environment, this chapter will help you get started with JUnit testing in no time.
Parallel testing with JUnit - Parallel Testing can be used to reduce test execution time and improve test efficiency. Learn how to perform parallel testing with JUnit.
Annotations in JUnit - When writing automation scripts with JUnit, we can use JUnit annotations to specify the type of methods in our test code. This helps us identify those methods when we run JUnit tests using Selenium WebDriver. Learn in detail what annotations are in JUnit.
Assertions in JUnit - Assertions are used to validate or test that the result of an action/functionality is the same as expected. Learn in detail what assertions are and how to use them while performing JUnit testing.
Parameterization in JUnit - Parameterized Test enables you to run the same automated test scripts with different variables. By collecting data on each method's test parameters, you can minimize time spent on writing tests. Learn how to use parameterization in JUnit.
Nested Tests In JUnit 5 - A nested class is a non-static class contained within another class in a hierarchical structure. It can share the state and setup of the outer class. Learn about nested annotations in JUnit 5 with examples.
Best practices for JUnit testing - Learn about the best practices, such as always testing key methods and classes, integrating JUnit tests with your build, and more to get the best possible results.
Advanced Use Cases for JUnit testing - Take a deep dive into the advanced use cases, such as how to run JUnit tests in Jupiter, how to use JUnit 5 Mockito for Unit testing, and more for JUnit testing.