Best junit code snippet using org.junit.runners.Annotation Type Parameterized.BeforeParam
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
JUnit 4 Expected Exception type
java: how to mock Calendar.getInstance()?
Changing names of parameterized tests
Mocking a class vs. mocking its interface
jUnit ignore @Test methods from base class
Important frameworks/tools to learn
Unit testing a Java Servlet
Meaning of delta or epsilon argument of assertEquals for double values
Different teardown for each @Test in jUnit
Best way to automagically migrate tests from JUnit 3 to JUnit 4?
There's actually an alternative to the @Test(expected=Xyz.class)
in JUnit 4.7 using Rule
and ExpectedException
In your test case you declare an ExpectedException
annotated with @Rule
, and assign it a default value of ExpectedException.none()
. Then in your test that expects an exception you replace the value with the actual expected value. The advantage of this is that without using the ugly try/catch method, you can further specify what the message within the exception was
@Rule public ExpectedException thrown= ExpectedException.none();
@Test
public void myTest() {
thrown.expect( Exception.class );
thrown.expectMessage("Init Gold must be >= 0");
rodgers = new Pirate("Dread Pirate Rodgers" , -100);
}
Using this method, you might be able to test for the message in the generic exception to be something specific.
ADDITION
Another advantage of using ExpectedException
is that you can more precisely scope the exception within the context of the test case. If you are only using @Test(expected=Xyz.class)
annotation on the test, then the Xyz exception can be thrown anywhere in the test code -- including any test setup or pre-asserts within the test method. This can lead to a false positive.
Using ExpectedException, you can defer specifying the thrown.expect(Xyz.class)
until after any setup and pre-asserts, just prior to actually invoking the method under test. Thus, you more accurately scope the exception to be thrown by the actual method invocation rather than any of the test fixture itself.
JUnit 5 NOTE:
JUnit 5 JUnit Jupiter has removed @Test(expected=...)
, @Rule
and ExpectedException
altogether. They are replaced with the new assertThrows()
, which requires the use of Java 8 and lambda syntax. ExpectedException
is still available for use in JUnit 5 through JUnit Vintage. Also JUnit Jupiter will also continue to support JUnit 4 ExpectedException
through use of the junit-jupiter-migrationsupport module, but only if you add an additional class-level annotation of @EnableRuleMigrationSupport
.
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