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How to use MockClassLoader class of org.powermock.core.classloader package
Best Powermock code snippet using org.powermock.core.classloader.MockClassLoader
Source:AbstractTestSuiteChunkerImpl.java 
...24import java.util.LinkedList;25import java.util.List;26import java.util.Set;27import java.util.Map.Entry;28import org.powermock.core.classloader.MockClassLoader;29import org.powermock.core.classloader.annotations.MockPolicy;30import org.powermock.core.classloader.annotations.PowerMockListener;31import org.powermock.core.classloader.annotations.PrepareEverythingForTest;32import org.powermock.core.classloader.annotations.PrepareForTest;33import org.powermock.core.classloader.annotations.PrepareOnlyThisForTest;34import org.powermock.core.classloader.annotations.SuppressStaticInitializationFor;35import org.powermock.core.classloader.interfaces.IPrepareEverythingForTest;36import org.powermock.core.spi.PowerMockPolicy;37import org.powermock.core.spi.PowerMockTestListener;38import org.powermock.core.transformers.MockTransformer;39import org.powermock.core.transformers.impl.MainMockTransformer;40import org.powermock.reflect.Whitebox;41import org.powermock.reflect.proxyframework.RegisterProxyFramework;42import org.powermock.tests.utils.ArrayMerger;43import org.powermock.tests.utils.IgnorePackagesExtractor;44import org.powermock.tests.utils.TestChunk;45import org.powermock.tests.utils.TestClassesExtractor;46import org.powermock.tests.utils.TestSuiteChunker;47/**48 * Abstract base class for test suite chunking, i.e. a suite is chunked into49 * several smaller pieces which are ran with different classloaders. A chunk is50 * defined by the {@link PrepareForTest} annotation. This to make sure that you51 * can byte-code manipulate classes in tests without impacting on other tests.52 * 53 */54public abstract class AbstractTestSuiteChunkerImpl<T> implements TestSuiteChunker {55 private static final int DEFAULT_TEST_LISTENERS_SIZE = 1;56 protected static final int NOT_INITIALIZED = -1;57 private static final int INTERNAL_INDEX_NOT_FOUND = NOT_INITIALIZED;58 protected final TestClassesExtractor prepareForTestExtractor = new PrepareForTestExtractorImpl();59 protected final TestClassesExtractor suppressionExtractor = new StaticConstructorSuppressExtractorImpl();60 private final IgnorePackagesExtractor ignorePackagesExtractor = new PowerMockIgnorePackagesExtractorImpl();61 private final ArrayMerger arrayMerger = new ArrayMergerImpl();62 private final Class<?>[] testClasses;63 /*64 * The classes listed in this set has been chunked and its delegates has65 * been created.66 */67 protected final Set<Class<?>> delegatesCreatedForTheseClasses = new LinkedHashSet<Class<?>>();68 // A list of junit delegates.69 protected final List<T> delegates = new LinkedList<T>();70 /*71 * Maps the list of test indexes that is assigned to a specific test suite72 * index.73 */74 protected final LinkedHashMap<Integer, List<Integer>> testAtDelegateMapper = new LinkedHashMap<Integer, List<Integer>>();75 private int currentTestIndex = NOT_INITIALIZED;76 /*77 * Maps between a specific class and a map of test methods loaded by a78 * specific mock class loader.79 */80 private final List<TestCaseEntry> internalSuites;81 protected volatile int testCount = NOT_INITIALIZED;82 protected AbstractTestSuiteChunkerImpl(Class<?> testClass) throws Exception {83 this(new Class[] { testClass });84 }85 protected AbstractTestSuiteChunkerImpl(Class<?>... testClasses) throws Exception {86 this.testClasses = testClasses;87 internalSuites = new LinkedList<TestCaseEntry>();88 for (Class<?> clazz : testClasses) {89 chunkClass(clazz);90 }91 }92 protected Object getPowerMockTestListenersLoadedByASpecificClassLoader(Class<?> clazz, ClassLoader classLoader) {93 try {94 int defaultListenerSize = DEFAULT_TEST_LISTENERS_SIZE;95 Class<?> annotationEnablerClass = null;96 try {97 annotationEnablerClass = Class.forName("org.powermock.api.extension.listener.AnnotationEnabler", false, classLoader);98 } catch (ClassNotFoundException e) {99 // Annotation enabler wasn't found in class path100 defaultListenerSize = 0;101 }102 registerProxyframework(classLoader);103 final Class<?> powerMockTestListenerType = Class.forName(PowerMockTestListener.class.getName(), false, classLoader);104 Object testListeners = null;105 if (clazz.isAnnotationPresent(PowerMockListener.class)) {106 PowerMockListener annotation = clazz.getAnnotation(PowerMockListener.class);107 final Class<? extends PowerMockTestListener>[] powerMockTestListeners = annotation.value();108 if (powerMockTestListeners.length > 0) {109 testListeners = Array.newInstance(powerMockTestListenerType, powerMockTestListeners.length + defaultListenerSize);110 for (int i = 0; i < powerMockTestListeners.length; i++) {111 String testListenerClassName = powerMockTestListeners[i].getName();112 final Class<?> listenerTypeLoadedByClassLoader = Class.forName(testListenerClassName, false, classLoader);113 Array.set(testListeners, i, Whitebox.newInstance(listenerTypeLoadedByClassLoader));114 }115 }116 } else {117 testListeners = Array.newInstance(powerMockTestListenerType, defaultListenerSize);118 }119 // Add default annotation enabler listener120 if (annotationEnablerClass != null) {121 Array.set(testListeners, Array.getLength(testListeners) - 1, Whitebox.newInstance(annotationEnablerClass));122 }123 return testListeners;124 } catch (ClassNotFoundException e) {125 throw new IllegalStateException("PowerMock internal error: Failed to load class.", e);126 }127 }128 private void registerProxyframework(ClassLoader classLoader) {129 Class<?> proxyFrameworkClass = null;130 try {131 proxyFrameworkClass = Class.forName("org.powermock.api.extension.proxyframework.ProxyFrameworkImpl", false, classLoader);132 } catch (ClassNotFoundException e) {133 throw new IllegalStateException(134 "Extension API internal error: org.powermock.api.extension.proxyframework.ProxyFrameworkImpl could not be located in classpath.");135 }136 Class<?> proxyFrameworkRegistrar = null;137 try {138 proxyFrameworkRegistrar = Class.forName(RegisterProxyFramework.class.getName(), false, classLoader);139 } catch (ClassNotFoundException e) {140 // Should never happen141 throw new RuntimeException(e);142 }143 try {144 Whitebox.invokeMethod(proxyFrameworkRegistrar, "registerProxyFramework", Whitebox.newInstance(proxyFrameworkClass));145 } catch (RuntimeException e) {146 throw e;147 } catch (Exception e) {148 throw new RuntimeException(e);149 }150 }151 protected void chunkClass(final Class<?> testClass) throws Exception {152 ClassLoader defaultMockLoader = null;153 final String[] ignorePackages = ignorePackagesExtractor.getPackagesToIgnore(testClass);154 if (testClass.isAnnotationPresent(PrepareEverythingForTest.class) || IPrepareEverythingForTest.class.isAssignableFrom(testClass)) {155 defaultMockLoader = createNewClassloader(testClass, new String[] { MockClassLoader.MODIFY_ALL_CLASSES }, ignorePackages);156 } else {157 final String[] prepareForTestClasses = prepareForTestExtractor.getTestClasses(testClass);158 final String[] suppressStaticClasses = suppressionExtractor.getTestClasses(testClass);159 defaultMockLoader = createNewClassloader(testClass, arrayMerger.mergeArrays(String.class, prepareForTestClasses, suppressStaticClasses),160 ignorePackages);161 if (defaultMockLoader instanceof MockClassLoader) {162 // Test class should always be prepared163 ((MockClassLoader) defaultMockLoader).addClassesToModify(testClass.getName());164 }165 }166 registerProxyframework(defaultMockLoader);167 List<Method> currentClassloaderMethods = new LinkedList<Method>();168 // Put the first suite in the map of internal suites.169 TestChunk defaultTestChunk = new TestChunkImpl(defaultMockLoader, currentClassloaderMethods);170 List<TestChunk> testChunks = new LinkedList<TestChunk>();171 testChunks.add(defaultTestChunk);172 internalSuites.add(new TestCaseEntry(testClass, testChunks));173 initEntries(internalSuites);174 /*175 * If we don't have any test that should be executed by the default176 * class loader remove it to avoid duplicate test print outs.177 */178 if (currentClassloaderMethods.isEmpty()) {179 internalSuites.get(0).getTestChunks().remove(0);180 }181 }182 public ClassLoader createNewClassloader(Class<?> testClass, final String[] classesToLoadByMockClassloader, final String[] packagesToIgnore) {183 ClassLoader mockLoader = null;184 if ((classesToLoadByMockClassloader == null || classesToLoadByMockClassloader.length == 0) && !hasMockPolicyProvidedClasses(testClass)) {185 mockLoader = Thread.currentThread().getContextClassLoader();186 } else {187 List<MockTransformer> mockTransformerChain = new ArrayList<MockTransformer>();188 final MainMockTransformer mainMockTransformer = new MainMockTransformer();189 mockTransformerChain.add(mainMockTransformer);190 mockLoader = AccessController.doPrivileged(new PrivilegedAction<MockClassLoader>() {191 public MockClassLoader run() {192 return new MockClassLoader(classesToLoadByMockClassloader, packagesToIgnore);193 }194 });195 MockClassLoader mockClassLoader = (MockClassLoader) mockLoader;196 mockClassLoader.setMockTransformerChain(mockTransformerChain);197 if (!mockClassLoader.shouldModifyAll()) {198 // Always prepare test class for testing if not all classes are199 // prepared200 mockClassLoader.addClassesToModify(testClass.getName());201 }202 new MockPolicyInitializerImpl(testClass).initialize(mockLoader);203 }204 return mockLoader;205 }206 /**207 * {@inheritDoc}208 */209 public void createTestDelegators(Class<?> testClass, List<TestChunk> chunks) throws Exception {210 for (TestChunk chunk : chunks) {211 ClassLoader classLoader = chunk.getClassLoader();212 List<Method> methodsToTest = chunk.getTestMethodsToBeExecutedByThisClassloader();213 T runnerDelegator = createDelegatorFromClassloader(classLoader, testClass, methodsToTest);214 delegates.add(runnerDelegator);215 }216 delegatesCreatedForTheseClasses.add(testClass);217 }218 protected abstract T createDelegatorFromClassloader(ClassLoader classLoader, Class<?> testClass, final List<Method> methodsToTest)219 throws Exception;220 private void initEntries(List<TestCaseEntry> entries) throws Exception {221 for (TestCaseEntry testCaseEntry : entries) {222 final Class<?> testClass = testCaseEntry.getTestClass();223 Method[] allMethods = testClass.getMethods();224 for (Method method : allMethods) {225 if (shouldExecuteTestForMethod(testClass, method)) {226 currentTestIndex++;227 if (hasChunkAnnotation(method)) {228 LinkedList<Method> methodsInThisChunk = new LinkedList<Method>();229 methodsInThisChunk.add(method);230 final String[] staticSuppressionClasses = getStaticSuppressionClasses(testClass, method);231 ClassLoader mockClassloader = null;232 if (method.isAnnotationPresent(PrepareEverythingForTest.class)) {233 mockClassloader = createNewClassloader(testClass, new String[] { MockClassLoader.MODIFY_ALL_CLASSES },234 ignorePackagesExtractor.getPackagesToIgnore(testClass));235 } else {236 mockClassloader = createNewClassloader(testClass, arrayMerger.mergeArrays(String.class, prepareForTestExtractor237 .getTestClasses(method), staticSuppressionClasses), ignorePackagesExtractor.getPackagesToIgnore(testClass));238 }239 TestChunkImpl chunk = new TestChunkImpl(mockClassloader, methodsInThisChunk);240 testCaseEntry.getTestChunks().add(chunk);241 updatedIndexes();242 } else {243 testCaseEntry.getTestChunks().get(0).getTestMethodsToBeExecutedByThisClassloader().add(method);244 // currentClassloaderMethods.add(method);245 final int currentDelegateIndex = internalSuites.size() - 1;246 /*247 * Add this test index to the main junit runner...
Source:MockClassLoaderTest.java
1package dux.org.powermock.core.classloader;23import org.junit.Before;4import org.junit.Test;5import org.powermock.core.classloader.MockClassLoader;67import com.github.docteurdux.test.AbstractTest;89public class MockClassLoaderTest extends AbstractTest {1011 public static class A {12 public String foo() {13 return "foo";14 }15 }1617 @Before18 public void before() {19 requireSources("powermock-core-1.6.4", MockClassLoader.class);20 }2122 @Test23 public void test() throws Exception {24 MockClassLoader mcl = new MockClassLoader(25 new String[] { "dux.org.powermock.core.classloader.MockClassLoaderTest$A" });26 ClassLoader cl = mcl;27 Class<?> clazz = cl.loadClass("dux.org.powermock.core.classloader.MockClassLoaderTest$A");28 Object o = clazz.newInstance();2930 }31}
...
MockClassLoader
Using AI Code Generation
1public class 4 {2 public static void main(String[] args) throws Exception {3 MockClassLoader mockClassLoader = new MockClassLoader();4 Class<?> clazz = mockClassLoader.loadClass("org.powermock.core.classloader.MockClassLoader");5 System.out.println(clazz);6 }7}8public class 5 {9 public static void main(String[] args) throws Exception {10 MockClassLoader mockClassLoader = new MockClassLoader();11 Class<?> clazz = mockClassLoader.loadClass("org.powermock.core.classloader.MockClassLoader");12 System.out.println(clazz);13 }14}15public class 6 {16 public static void main(String[] args) throws Exception {17 MockClassLoader mockClassLoader = new MockClassLoader();18 Class<?> clazz = mockClassLoader.loadClass("org.powermock.core.classloader.MockClassLoader");19 System.out.println(clazz);20 }21}22public class 7 {23 public static void main(String[] args) throws Exception {24 MockClassLoader mockClassLoader = new MockClassLoader();25 Class<?> clazz = mockClassLoader.loadClass("org.powermock.core.classloader.MockClassLoader");26 System.out.println(clazz);27 }28}29public class 8 {30 public static void main(String[] args) throws Exception {31 MockClassLoader mockClassLoader = new MockClassLoader();32 Class<?> clazz = mockClassLoader.loadClass("org.powermock.core.classloader.MockClassLoader");33 System.out.println(clazz);34 }35}36public class 9 {37 public static void main(String[] args) throws Exception {38 MockClassLoader mockClassLoader = new MockClassLoader();39 Class<?> clazz = mockClassLoader.loadClass("org.powermock.core.classloader.MockClassLoader");40 System.out.println(clazz);41 }42}43public class 10 {44 public static void main(String[] args) throws Exception {45 MockClassLoader mockClassLoader = new MockClassLoader();
MockClassLoader
Using AI Code Generation
1package org.powermock.core.classloader;2import java.io.IOException;3import java.io.InputStream;4import java.net.URL;5import java.net.URLConnection;6import java.net.URLStreamHandler;7import java.util.HashMap;8import java.util.Map;9public class MockClassLoader extends ClassLoader {10 private final Map<String, byte[]> byteCodeMap = new HashMap<String, byte[]>();11 public MockClassLoader() {12 super(MockClassLoader.class.getClassLoader());13 }14 public void addClass(String className, byte[] byteCode) {15 byteCodeMap.put(className, byteCode);16 }17 protected Class<?> findClass(String name) throws ClassNotFoundException {18 byte[] byteCode = byteCodeMap.get(name);19 if (byteCode == null) {20 throw new ClassNotFoundException(name);21 }22 return defineClass(name, byteCode, 0, byteCode.length);23 }24 public URL getResource(String name) {25 if (byteCodeMap.containsKey(name)) {26 try {27 return new URL(null, name, new URLStreamHandler() {28 protected URLConnection openConnection(URL u) throws IOException {29 return new URLConnection(u) {30 public void connect() throws IOException {31 }32 public InputStream getInputStream() throws IOException {33 return new InputStream() {34 private int index;35 public int read() throws IOException {36 return index < byteCodeMap.get(name).length ? byteCodeMap.get(name)[index++]37 : -1;38 }39 };40 }41 };42 }43 });44 } catch (Exception e) {45 throw new RuntimeException(e);46 }47 } else {48 return super.getResource(name);49 }50 }51}52import java.io.ByteArrayOutputStream;53import java.io.IOException;54import java.io.InputStream;55import java.lang.reflect.InvocationTargetException;56import java.lang.reflect.Method;57import java.net.URL;58import java.net.URLClassLoader;59import org.powermock.core.classloader.MockClassLoader;60public class TestMockClassLoader {61 public static void main(String[] args) throws Exception {62 URLClassLoader classLoader = new URLClassLoader(new URL[] { new URL("file:/C:/") });63 MockClassLoader mockClassLoader = new MockClassLoader();64 mockClassLoader.addClass("MyClass", getByteCode());
MockClassLoader
Using AI Code Generation
1package com.journaldev.powermock;2import java.lang.reflect.Method;3import org.powermock.core.classloader.MockClassLoader;4public class MockClassLoaderTest {5 public static void main(String[] args) throws Exception {6 String className = "com.journaldev.powermock.TestClass";7 String methodName = "test";8 byte[] classBytes = new byte[] {-54, -2, -70, -66, 0, 0, 0, 52, 0, 18, 10, 0, 3, 0, 4, 7, 0, 5, 7, 0, 6, 1, 0, 4, 116, 101, 115, 116, 1, 0, 3, 40, 41, 86, 1, 0, 4, 67, 111, 100, 101, 1, 0, 15, 76, 105, 110, 101, 78, 117, 109, 98, 101, 114, 84, 97, 98, 108, 101, 1, 0, 4, 109, 97, 105, 110, 1, 0, 22, 40, 91, 76, 106, 97, 118, 97, 47, 108, 97, 110, 103, 47, 83, 116, 114, 105, 110, 103, 59, 41, 86, 12, 0, 7, 0, 8, 1, 0, 16, 106, 97, 118, 97, 47, 108, 97, 110, 103, 47, 79, 98, 106, 101, 99, 116, 1, 0, 19, 106, 97, 118, 97, 47, 108, 97, 110, 103, 47, 83, 121, 115, 116, 101, 109, 7, 0, 10, 12, 0
MockClassLoader
Using AI Code Generation
1public class TestClass {2 public static void main(String args[]) throws Exception {3 MockClassLoader mockClassLoader = new MockClassLoader();4 Class<?> clazz = mockClassLoader.loadClass("com.test.Test");5 Method method = clazz.getMethod("test");6 method.invoke(clazz.newInstance());7 }8}9public class TestClass {10 public static void main(String args[]) throws Exception {11 MockClassLoader mockClassLoader = new MockClassLoader();12 Class<?> clazz = mockClassLoader.loadClass("com.test.Test");13 Method method = clazz.getMethod("test");14 method.invoke(clazz.newInstance());15 }16}17public class TestClass {18 public static void main(String args[]) throws Exception {19 MockClassLoader mockClassLoader = new MockClassLoader();20 Class<?> clazz = mockClassLoader.loadClass("com.test.Test");21 Method method = clazz.getMethod("test");22 method.invoke(clazz.newInstance());23 }24}25public class TestClass {26 public static void main(String args[]) throws Exception {27 MockClassLoader mockClassLoader = new MockClassLoader();28 Class<?> clazz = mockClassLoader.loadClass("com.test.Test");29 Method method = clazz.getMethod("test");30 method.invoke(clazz.newInstance());31 }32}33public class TestClass {34 public static void main(String args[]) throws Exception {35 MockClassLoader mockClassLoader = new MockClassLoader();36 Class<?> clazz = mockClassLoader.loadClass("com.test.Test");37 Method method = clazz.getMethod("test");38 method.invoke(clazz.newInstance());39 }40}41public class TestClass {42 public static void main(String args[]) throws Exception {43 MockClassLoader mockClassLoader = new MockClassLoader();44 Class<?> clazz = mockClassLoader.loadClass("com.test.Test
MockClassLoader
Using AI Code Generation
1@PrepareForTest(value = {4.class}, loader = MockClassLoader.class, path = "path to the class to be loaded")2public class 4Test {3 public void test() {4 }5}6public class 5 {7 public static String staticMethod() {8 return "static method";9 }10}11@RunWith(PowerMockRunner.class)12@PrepareForTest({5.class})13public class 5Test {14 public void testStaticMethod() {15 PowerMockito.mockStatic(5.class);16 when(5.staticMethod()).thenReturn("mocked static method");17 String result = 5.staticMethod();18 assertEquals("mocked static method", result);19 }20}21public final class 6 {22 public String method() {23 return "method";24 }25}26@RunWith(PowerMockRunner.class)27@PrepareForTest({6.class})28public class 6Test {29 public void testMethod() {
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