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How to use Annotation Type Parameterized.BeforeParam class of org.junit.runners package
Best junit code snippet using org.junit.runners.Annotation Type Parameterized.BeforeParam
Source:BlockJUnit4ClassRunnerWithParameters.java 
1package org.junit.runners.parameterized;2import java.lang.annotation.Annotation;3import java.lang.reflect.Field;4import java.util.List;5import org.junit.internal.runners.statements.RunAfters;6import org.junit.internal.runners.statements.RunBefores;7import org.junit.runner.RunWith;8import org.junit.runner.notification.RunNotifier;9import org.junit.runners.BlockJUnit4ClassRunner;10import org.junit.runners.Parameterized;11import org.junit.runners.Parameterized.Parameter;12import org.junit.runners.model.FrameworkField;13import org.junit.runners.model.FrameworkMethod;14import org.junit.runners.model.InitializationError;15import org.junit.runners.model.Statement;16/**17 * A {@link BlockJUnit4ClassRunner} with parameters support. Parameters can be18 * injected via constructor or into annotated fields.19 */20public class BlockJUnit4ClassRunnerWithParameters extends21 BlockJUnit4ClassRunner {22 private enum InjectionType {23 CONSTRUCTOR, FIELD24 }25 private final Object[] parameters;26 private final String name;27 public BlockJUnit4ClassRunnerWithParameters(TestWithParameters test)28 throws InitializationError {29 super(test.getTestClass());30 parameters = test.getParameters().toArray(31 new Object[test.getParameters().size()]);32 name = test.getName();33 }34 @Override35 public Object createTest() throws Exception {36 InjectionType injectionType = getInjectionType();37 switch (injectionType) {38 case CONSTRUCTOR:39 return createTestUsingConstructorInjection();40 case FIELD:41 return createTestUsingFieldInjection();42 default:43 throw new IllegalStateException("The injection type "44 + injectionType + " is not supported.");45 }46 }47 private Object createTestUsingConstructorInjection() throws Exception {48 return getTestClass().getOnlyConstructor().newInstance(parameters);49 }50 private Object createTestUsingFieldInjection() throws Exception {51 List<FrameworkField> annotatedFieldsByParameter = getAnnotatedFieldsByParameter();52 if (annotatedFieldsByParameter.size() != parameters.length) {53 throw new Exception(54 "Wrong number of parameters and @Parameter fields."55 + " @Parameter fields counted: "56 + annotatedFieldsByParameter.size()57 + ", available parameters: " + parameters.length58 + ".");59 }60 Object testClassInstance = getTestClass().getJavaClass().newInstance();61 for (FrameworkField each : annotatedFieldsByParameter) {62 Field field = each.getField();63 Parameter annotation = field.getAnnotation(Parameter.class);64 int index = annotation.value();65 try {66 field.set(testClassInstance, parameters[index]);67 } catch (IllegalAccessException e) {68 IllegalAccessException wrappedException = new IllegalAccessException(69 "Cannot set parameter '" + field.getName()70 + "'. Ensure that the field '" + field.getName()71 + "' is public.");72 wrappedException.initCause(e);73 throw wrappedException;74 } catch (IllegalArgumentException iare) {75 throw new Exception(getTestClass().getName()76 + ": Trying to set " + field.getName()77 + " with the value " + parameters[index]78 + " that is not the right type ("79 + parameters[index].getClass().getSimpleName()80 + " instead of " + field.getType().getSimpleName()81 + ").", iare);82 }83 }84 return testClassInstance;85 }86 @Override87 protected String getName() {88 return name;89 }90 @Override91 protected String testName(FrameworkMethod method) {92 return method.getName() + getName();93 }94 @Override95 protected void validateConstructor(List<Throwable> errors) {96 validateOnlyOneConstructor(errors);97 if (getInjectionType() != InjectionType.CONSTRUCTOR) {98 validateZeroArgConstructor(errors);99 }100 }101 @Override102 protected void validateFields(List<Throwable> errors) {103 super.validateFields(errors);104 if (getInjectionType() == InjectionType.FIELD) {105 List<FrameworkField> annotatedFieldsByParameter = getAnnotatedFieldsByParameter();106 int[] usedIndices = new int[annotatedFieldsByParameter.size()];107 for (FrameworkField each : annotatedFieldsByParameter) {108 int index = each.getField().getAnnotation(Parameter.class)109 .value();110 if (index < 0 || index > annotatedFieldsByParameter.size() - 1) {111 errors.add(new Exception("Invalid @Parameter value: "112 + index + ". @Parameter fields counted: "113 + annotatedFieldsByParameter.size()114 + ". Please use an index between 0 and "115 + (annotatedFieldsByParameter.size() - 1) + "."));116 } else {117 usedIndices[index]++;118 }119 }120 for (int index = 0; index < usedIndices.length; index++) {121 int numberOfUse = usedIndices[index];122 if (numberOfUse == 0) {123 errors.add(new Exception("@Parameter(" + index124 + ") is never used."));125 } else if (numberOfUse > 1) {126 errors.add(new Exception("@Parameter(" + index127 + ") is used more than once (" + numberOfUse + ")."));128 }129 }130 }131 }132 @Override133 protected Statement classBlock(RunNotifier notifier) {134 Statement statement = childrenInvoker(notifier);135 statement = withBeforeParams(statement);136 statement = withAfterParams(statement);137 return statement;138 }139 private Statement withBeforeParams(Statement statement) {140 List<FrameworkMethod> befores = getTestClass()141 .getAnnotatedMethods(Parameterized.BeforeParam.class);142 return befores.isEmpty() ? statement : new RunBeforeParams(statement, befores);143 }144 private class RunBeforeParams extends RunBefores {145 RunBeforeParams(Statement next, List<FrameworkMethod> befores) {146 super(next, befores, null);147 }148 @Override149 protected void invokeMethod(FrameworkMethod method) throws Throwable {150 int paramCount = method.getMethod().getParameterTypes().length;151 method.invokeExplosively(null, paramCount == 0 ? (Object[]) null : parameters);152 }153 }154 private Statement withAfterParams(Statement statement) {155 List<FrameworkMethod> afters = getTestClass()156 .getAnnotatedMethods(Parameterized.AfterParam.class);157 return afters.isEmpty() ? statement : new RunAfterParams(statement, afters);158 }159 private class RunAfterParams extends RunAfters {160 RunAfterParams(Statement next, List<FrameworkMethod> afters) {161 super(next, afters, null);162 }163 @Override164 protected void invokeMethod(FrameworkMethod method) throws Throwable {165 int paramCount = method.getMethod().getParameterTypes().length;166 method.invokeExplosively(null, paramCount == 0 ? (Object[]) null : parameters);167 }168 }169 @Override170 protected Annotation[] getRunnerAnnotations() {171 Annotation[] allAnnotations = super.getRunnerAnnotations();172 Annotation[] annotationsWithoutRunWith = new Annotation[allAnnotations.length - 1];173 int i = 0;174 for (Annotation annotation: allAnnotations) {175 if (!annotation.annotationType().equals(RunWith.class)) {176 annotationsWithoutRunWith[i] = annotation;177 ++i;178 }179 }180 return annotationsWithoutRunWith;181 }182 private List<FrameworkField> getAnnotatedFieldsByParameter() {183 return getTestClass().getAnnotatedFields(Parameter.class);184 }185 private InjectionType getInjectionType() {186 if (fieldsAreAnnotated()) {187 return InjectionType.FIELD;188 } else {189 return InjectionType.CONSTRUCTOR;190 }191 }192 private boolean fieldsAreAnnotated() {193 return !getAnnotatedFieldsByParameter().isEmpty();194 }195}...
Annotation Type Parameterized.BeforeParam
Using AI Code Generation
1import org.junit.runner.RunWith;2import org.junit.runners.Parameterized;3import org.junit.runners.Parameterized.Parameters;4import java.util.Arrays;5import java.util.Collection;6@RunWith(Parameterized.class)7public class BeforeParam {8 public static Collection<Object[]> data() {9 return Arrays.asList(new Object[][] { { "is" }, { "a" }, { "test" } });10 }11 private String fInput;12 public BeforeParam(String input) {13 fInput = input;14 }15}16import static org.junit.Assert.assertEquals;17import org.junit.Test;18import org.junit.runner.RunWith;19import org.junit.runners.Parameterized;20import org.junit.runners.Parameterized.Parameters;21import java.util.Arrays;22import java.util.Collection;23@RunWith(Parameterized.class)24public class AfterParam {25 public static Collection<Object[]> data() {26 return Arrays.asList(new Object[][] { { "is" }, { "a" }, { "test" } });27 }28 private String fInput;29 public AfterParam(String input) {30 fInput = input;31 }32 public void test() {33 assertEquals("a", fInput);34 }35}36import static org.junit.Assert.assertEquals;37import org.junit.Test;38import org.junit.runner.RunWith;39import org.junit.runners.Parameterized;40import org.junit.runners.Parameterized.Parameters;41import java.util.Arrays;42import java.util.Collection;43@RunWith(Parameterized.class)44public class BeforeParam {45 public static Collection<Object[]> data() {46 return Arrays.asList(new Object[][] { { "is" }, { "a" }, { "test" } });47 }48 private String fInput;49 public BeforeParam(String input) {50 fInput = input;51 }52 public void test() {53 assertEquals("a", fInput);54 }55}56import static org.junit.Assert.assertEquals;57import org.junit.Test;58import org.junit.runner.RunWith;59import org.junit.runners.Parameterized;60import org.junit.runners.Parameterized.Parameters;61import java.util.Arrays;62import java.util.Collection;63@RunWith(Parameterized.class)64public class AfterParam {65 public static Collection<Object[]> data() {66 return Arrays.asList(new Object[][] {
Annotation Type Parameterized.BeforeParam
Using AI Code Generation
1import java.util.Arrays;2import java.util.Collection;3import org.junit.Test;4import org.junit.runner.RunWith;5import org.junit.runners.Parameterized;6import org.junit.runners.Parameterized.Parameters;7@RunWith(Parameterized.class)8public class TestParameterized {9 public static Collection<Object[]> data(){10 return Arrays.asList(new Object[][] {11 {1, 2}, {5, 3}, {121, 4}12 });13 }14 private int input;15 private int expected;16 public TestParameterized(int input, int expected) {17 this.input = input;18 this.expected = expected;19 }20 public void test() {21 System.out.println(input + " " + expected);22 }23}24import java.util.Arrays;25import java.util.Collection;26import org.junit.Test;27import org.junit.runner.RunWith;28import org.junit.runners.Parameterized;29import org.junit.runners.Parameterized.Parameters;30@RunWith(Parameterized.class)31public class TestParameterized {32 public static Collection<Object[]> data(){33 return Arrays.asList(new Object[][] {34 {1, 2}, {5, 3}, {121, 4}35 });36 }37 private int input;38 private int expected;39 public TestParameterized(int input, int expected) {40 this.input = input;41 this.expected = expected;42 }43 public void test() {44 System.out.println(input + " " + expected);45 }46}47import java.util.Arrays;48import java.util.Collection;49import org.junit.Test;50import org.junit.runner.RunWith;51import org.junit.runners.Parameterized;52import org.junit.runners.Parameterized.Parameters;53@RunWith(Parameterized.class)54public class TestParameterized {55 public static Collection<Object[]> data(){56 return Arrays.asList(new Object[][] {57 {1, 2}, {5, 3}, {121, 4}58 });59 }60 private int input;61 private int expected;62 public TestParameterized(int input, int expected) {63 this.input = input;
Annotation Type Parameterized.BeforeParam
Using AI Code Generation
1import org.junit.runners.Parameterized;2import java.util.Arrays;3import java.util.Collection;4import org.junit.Before;5import org.junit.Test;6import org.junit.runner.RunWith;7import static org.junit.Assert.*;8@RunWith(Parameterized.class)9public class BeforeParamTest {10 private int number;11 private boolean result;12 public void initialize() {13 System.out.println("BeforeParamTest.initialize()");14 }15 public BeforeParamTest(int number, boolean result) {16 this.number = number;17 this.result = result;18 }19 public static Collection primeNumbers() {20 return Arrays.asList(new Object[][] {21 { 2, true },22 { 6, false },23 { 19, true },24 { 22, false },25 { 23, true }26 });27 }28 public void testPrimeNumberChecker() {29 System.out.println("Parameterized Number is : " + number);30 assertEquals(result, BeforeParamTest.isPrime(number));31 }32 private static boolean isPrime(int number) {33 for(int i=2; i < (number/2); i++) {34 if(number % i == 0) {35 return false;36 }37 }38 return true;39 }40}41BeforeParamTest.initialize()42BeforeParamTest.initialize()43BeforeParamTest.initialize()44BeforeParamTest.initialize()45BeforeParamTest.initialize()46package com.journaldev.junit;47import org.junit.runners.Parameterized;48import java.util.Arrays;49import java.util.Collection;50import org.junit.Before;51import org.junit.Rule;52import org.junit.Test;53import org.junit.runner.RunWith;54import org.junit.rules.ExpectedException;55import static org.junit.Assert.*;56@RunWith(Parameterized.class)57public class BeforeParamRuleTest {58 private int number;59 private boolean result;60 public ExpectedException thrown = ExpectedException.none();
Annotation Type Parameterized.BeforeParam
Using AI Code Generation
1@RunWith(Parameterized.class)2public class TestJunit1 {3 private String name;4 private int age;5 public TestJunit1(String name, int age) {6 this.name = name;7 this.age = age;8 }9 public String getName() {10 return name;11 }12 public int getAge() {13 return age;14 }15 public static Collection<Object[]> data() {16 Object[][] data = new Object[][] { { "John", 20 }, { "Steve", 30 }, { "Bill", 40 } };17 return Arrays.asList(data);18 }19 public void test() {20 System.out.println("Parameterized name is : " + name);21 System.out.println("Parameterized age is : " + age);22 }23}24@RunWith(Parameterized.class)25public class TestJunit1 {26 private String name;27 private int age;28 public TestJunit1(String name, int age) {29 this.name = name;30 this.age = age;31 }32 public String getName() {33 return name;34 }35 public int getAge() {36 return age;37 }38 public static Collection<Object[]> data() {39 Object[][] data = new Object[][] { { "John", 20 }, { "Steve", 30 }, { "Bill", 40 } };40 return Arrays.asList(data);41 }42 public void test() {43 System.out.println("Parameterized name is : " + name);44 System.out.println("Parameterized age is : " + age);45 }46 public void beforeParam() {47 System.out.println("Before
Annotation Type Parameterized.BeforeParam
Using AI Code Generation
1@RunWith(Parameterized.class)2public class ParameterizedTest {3 private int number;4 public ParameterizedTest(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}15@RunWith(Parameterized.class)16public class ParameterizedTest {17public ParameterizedTest(int number) {18this.number = number;19public static Collection<Object[]> data() {20Object[][] data = new Object[][] { { 1 }, { 2 }, { 3 }, { 4 }, { 5 } };21return Arrays.asList(data);22assertTrue(number > 0 && number < 6);23I am using JUnit 4.12 and I have imported the following:24import org.junit.Test;25import org
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