KaneAI - World’s First E2E Software Testing Agent.Book a Demo Join TestMu Conference

How to use BytecodeGenerator class of org.mockito.internal.creation.bytebuddy package

Best Mockito code snippet using org.mockito.internal.creation.bytebuddy.BytecodeGenerator

Source:InlineByteBuddyMockMaker.java

...21import java.lang.reflect.Modifier;22import java.util.jar.JarEntry;23import java.util.jar.JarFile;24import java.util.jar.JarOutputStream;25import static org.mockito.internal.creation.bytebuddy.InlineBytecodeGenerator.EXCLUDES;26import static org.mockito.internal.util.StringUtil.join;27/**28 * Agent and subclass based mock maker.29 * <p>30 * This mock maker which uses a combination of the Java instrumentation API and sub-classing rather than creating31 * a new sub-class to create a mock. This way, it becomes possible to mock final types and methods. This mock32 * maker <strong>must to be activated explicitly</strong> for supporting mocking final types and methods:33 * <p>34 * <p>35 * This mock maker can be activated by creating the file <code>/mockito-extensions/org.mockito.plugins.MockMaker</code>36 * containing the text <code>mock-maker-inline</code> or <code>org.mockito.internal.creation.bytebuddy.InlineByteBuddyMockMaker</code>.37 * <p>38 * <p>39 * This mock maker will make a best effort to avoid subclass creation when creating a mock. Otherwise it will use the40 * <code>org.mockito.internal.creation.bytebuddy.SubclassByteBuddyMockMaker</code> to create the mock class. That means41 * that the following condition is true42 * <p>43 * <pre class="code"><code class="java">44 * class Foo { }45 * assert mock(Foo.class).getClass() == Foo.class;46 * </pre></code>47 * <p>48 * unless any of the following conditions is met, in such case the mock maker <em>fall backs</em> to the49 * the creation of a subclass.50 * <p>51 * <ul>52 * <li>the type to mock is an abstract class.</li>53 * <li>the mock is set to require additional interfaces.</li>54 * <li>the mock is <a href="#20">explicitly set to support serialization</a>.</li>55 * </ul>56 * <p>57 * <p>58 * Some type of the JDK cannot be mocked, this includes <code>Class</code>, <code>String</code>, and wrapper types.59 * <p>60 * <p>61 * Nevertheless, final methods of such types are mocked when using the inlining mock maker. Mocking final types and enums62 * does however remain impossible when explicitly requiring serialization support or when adding ancillary interfaces.63 * <p>64 * <p>65 * Important behavioral changes when using inline-mocks:66 * <ul>67 * <li>Mockito is capable of mocking package-private methods even if they are defined in different packages than68 * the mocked type. Mockito voluntarily never mocks package-visible methods within <code>java.*</code> packages.</li>69 * <li>Additionally to final types, Mockito can now mock types that are not visible for extension; such types70 * include private types in a protected package.</li>71 * <li>Mockito can no longer mock <code>native</code> methods. Inline mocks require byte code manipulation of a72 * method where native methods do not offer any byte code to manipulate.</li>73 * <li>Mockito cannot longer strip <code>synchronized</code> modifiers from mocked instances.</li>74 * </ul>75 * <p>76 * <p>77 * Note that inline mocks require a Java agent to be attached. Mockito will attempt an attachment of a Java agent upon78 * loading the mock maker for creating inline mocks. Such runtime attachment is only possible when using a JVM that79 * is part of a JDK or when using a Java 9 VM. When running on a non-JDK VM prior to Java 9, it is however possible to80 * manually add the <a href="http://bytebuddy.net">Byte Buddy Java agent jar</a> using the <code>-javaagent</code>81 * parameter upon starting the JVM. Furthermore, the inlining mock maker requires the VM to support class retransformation82 * (also known as HotSwap). All major VM distributions such as HotSpot (OpenJDK), J9 (IBM/Websphere) or Zing (Azul)83 * support this feature.84 */85@Incubating86public class InlineByteBuddyMockMaker implements ClassCreatingMockMaker {87    private static final Instrumentation INSTRUMENTATION;88    private static final Throwable INITIALIZATION_ERROR;89    static {90        Instrumentation instrumentation;91        Throwable initializationError = null;92        try {93            try {94                instrumentation = ByteBuddyAgent.install();95                if (!instrumentation.isRetransformClassesSupported()) {96                    throw new IllegalStateException(join(97                            "Byte Buddy requires retransformation for creating inline mocks. This feature is unavailable on the current VM.",98                            "",99                            "You cannot use this mock maker on this VM"));100                }101                File boot = File.createTempFile("mockitoboot", ".jar");102                boot.deleteOnExit();103                JarOutputStream outputStream = new JarOutputStream(new FileOutputStream(boot));104                try {105                    String source = "org/mockito/internal/creation/bytebuddy/MockMethodDispatcher";106                    InputStream inputStream = InlineByteBuddyMockMaker.class.getClassLoader().getResourceAsStream(source + ".raw");107                    if (inputStream == null) {108                        throw new IllegalStateException(join(109                                "The MockMethodDispatcher class file is not locatable: " + source + ".raw",110                                "",111                                "The class loader responsible for looking up the resource: " + InlineByteBuddyMockMaker.class.getClassLoader()112                        ));113                    }114                    outputStream.putNextEntry(new JarEntry(source + ".class"));115                    try {116                        int length;117                        byte[] buffer = new byte[1024];118                        while ((length = inputStream.read(buffer)) != -1) {119                            outputStream.write(buffer, 0, length);120                        }121                    } finally {122                        inputStream.close();123                    }124                    outputStream.closeEntry();125                } finally {126                    outputStream.close();127                }128                instrumentation.appendToBootstrapClassLoaderSearch(new JarFile(boot));129                try {130                    Class<?> dispatcher = Class.forName("org.mockito.internal.creation.bytebuddy.MockMethodDispatcher");131                    if (dispatcher.getClassLoader() != null) {132                        throw new IllegalStateException(join(133                                "The MockMethodDispatcher must not be loaded manually but must be injected into the bootstrap class loader.",134                                "",135                                "The dispatcher class was already loaded by: " + dispatcher.getClassLoader()));136                    }137                } catch (ClassNotFoundException cnfe) {138                    throw new IllegalStateException(join(139                            "Mockito failed to inject the MockMethodDispatcher class into the bootstrap class loader",140                            "",141                            "It seems like your current VM does not support the instrumentation API correctly."), cnfe);142                }143            } catch (IOException ioe) {144                throw new IllegalStateException(join(145                        "Mockito could not self-attach a Java agent to the current VM. This feature is required for inline mocking.",146                        "This error occured due to an I/O error during the creation of this agent: " + ioe,147                        "",148                        "Potentially, the current VM does not support the instrumentation API correctly"), ioe);149            }150        } catch (Throwable throwable) {151            instrumentation = null;152            initializationError = throwable;153        }154        INSTRUMENTATION = instrumentation;155        INITIALIZATION_ERROR = initializationError;156    }157    private final BytecodeGenerator bytecodeGenerator;158    private final WeakConcurrentMap<Object, MockMethodInterceptor> mocks = new WeakConcurrentMap.WithInlinedExpunction<Object, MockMethodInterceptor>();159    public InlineByteBuddyMockMaker() {160        if (INITIALIZATION_ERROR != null) {161            throw new MockitoInitializationException(join(162                    "Could not initialize inline Byte Buddy mock maker. (This mock maker is not supported on Android.)",163                    "",164                    Platform.describe()), INITIALIZATION_ERROR);165        }166        bytecodeGenerator = new TypeCachingBytecodeGenerator(new InlineBytecodeGenerator(INSTRUMENTATION, mocks), true);167    }168    @Override169    public <T> T createMock(MockCreationSettings<T> settings, MockHandler handler) {170        Class<? extends T> type = createMockType(settings);171        Instantiator instantiator = Plugins.getInstantiatorProvider().getInstantiator(settings);172        try {173            T instance = instantiator.newInstance(type);174            MockMethodInterceptor mockMethodInterceptor = new MockMethodInterceptor(handler, settings);175            mocks.put(instance, mockMethodInterceptor);176            if (instance instanceof MockAccess) {177                ((MockAccess) instance).setMockitoInterceptor(mockMethodInterceptor);178            }179            return instance;180        } catch (org.mockito.internal.creation.instance.InstantiationException e) {...

Source:TypeCachingBytecodeGenerator.java

...7import org.mockito.mock.SerializableMode;8import java.lang.ref.ReferenceQueue;9import java.util.Set;10import java.util.concurrent.Callable;11class TypeCachingBytecodeGenerator extends ReferenceQueue<ClassLoader> implements BytecodeGenerator {12    private final Object BOOTSTRAP_LOCK = new Object();13    private final BytecodeGenerator bytecodeGenerator;14    private final TypeCache<MockitoMockKey> typeCache;15    public TypeCachingBytecodeGenerator(BytecodeGenerator bytecodeGenerator, boolean weak) {16        this.bytecodeGenerator = bytecodeGenerator;17        typeCache = new TypeCache.WithInlineExpunction<MockitoMockKey>(weak ? TypeCache.Sort.WEAK : TypeCache.Sort.SOFT);18    }19    @SuppressWarnings("unchecked")20    @Override21    public <T> Class<T> mockClass(final MockFeatures<T> params) {22        try {23            ClassLoader classLoader = params.mockedType.getClassLoader();24            return (Class<T>) typeCache.findOrInsert(classLoader,25                    new MockitoMockKey(params.mockedType, params.interfaces, params.serializableMode, params.stripAnnotations),26                    new Callable<Class<?>>() {27                        @Override28                        public Class<?> call() throws Exception {29                            return bytecodeGenerator.mockClass(params);...

BytecodeGenerator

Using AI Code Generation

1import net.bytebuddy.ByteBuddy;2import net.bytebuddy.description.method.MethodDescription;3import net.bytebuddy.dynamic.DynamicType;4import net.bytebuddy.dynamic.loading.ClassLoadingStrategy;5import net.bytebuddy.implementation.InvocationHandlerAdapter;6import net.bytebuddy.matcher.ElementMatchers;7import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor;8import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.DispatcherDefaultingToRealMethod;9import java.lang.reflect.Method;10import static net.bytebuddy.matcher.ElementMatchers.any;11public class BytecodeGenerator {12    public static void main(String[] args) throws Exception {13        DynamicType.Builder<?> builder = new ByteBuddy()14                .subclass(Object.class)15                .name("foo.Bar")16                .method(any())17                .intercept(InvocationHandlerAdapter.of(new MockMethodInterceptor(new DispatcherDefaultingToRealMethod())));18        Class<?> dynamicType = builder.make()19                .load(BytecodeGenerator.class.getClassLoader(), ClassLoadingStrategy.Default.WRAPPER)20                .getLoaded();21        Object instance = dynamicType.newInstance();22        Method method = dynamicType.getMethod("toString");23        System.out.println(method.invoke(instance));24    }25}26import net.bytebuddy.ByteBuddy;27import net.bytebuddy.description.method.MethodDescription;28import net.bytebuddy.dynamic.DynamicType;29import net.bytebuddy.dynamic.loading.ClassLoadingStrategy;30import net.bytebuddy.implementation.InvocationHandlerAdapter;31import net.bytebuddy.matcher.ElementMatchers;32import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor;33import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.DispatcherDefaultingToRealMethod;34import java.lang.reflect.Method;35import static net.bytebuddy.matcher.ElementMatchers.any;36public class BytecodeGenerator {37    public static void main(String[] args) throws Exception {38        DynamicType.Builder<?> builder = new ByteBuddy()39                .subclass(Object.class)40                .name("foo.Bar")41                .method(any())42                .intercept(InvocationHandlerAdapter.of(new MockMethodInterceptor(new DispatcherDefaultingToRealMethod())));43        Class<?> dynamicType = builder.make()44                .load(BytecodeGenerator.class.getClassLoader(), ClassLoadingStrategy.Default.WRAPPER)45                .getLoaded();46        Object instance = dynamicType.newInstance();47        Method method = dynamicType.getMethod("toString");48        System.out.println(method.invoke(instance));49    }50}

BytecodeGenerator

Using AI Code Generation

1import org.mockito.internal.creation.bytebuddy.BytecodeGenerator;2import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor;3import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.DispatcherDefaultingToRealMethod;4import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.DispatcherIgnoringStubs;5import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.DispatcherNotifyingMockHandler;6import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.DispatcherSafe;7import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.DispatcherSafeWithStubs;8import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.DispatcherToRealMethod;9import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.DispatcherToRealMethodInSequence;10import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.DispatcherToReturnValues;11import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.DispatcherToThrowException;12import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.Interceptor;13import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.InterceptorSafe;14import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.InterceptorSafeWithStubs;15import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.InterceptorToRealMethod;16import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.InterceptorToRealMethodInSequence;17import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.InterceptorToReturnValues;18import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.InterceptorToThrowException;19import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.SimpleMockMethodInterceptor;20import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor.SimpleMockMethodInterceptorWithStubs;21import org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator;22import org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator.CacheProvider;23import org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator.CachedBytecodeGenerator;24import org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator.CachedBytecodeGeneratorWithMockitoClassloader;25import org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator.CachingMockitoClassloader;26import org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator.DefaultCacheProvider;27import org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator.DefaultCacheProvider.BootstrapClassLoaderProvider;28import org.mockito.internal.creation.bytebuddy.TypeCachingBytecodeGenerator.DefaultCacheProvider.BootstrapClassLoaderProvider.BootstrapClassLoader;29import org.mockito.internal.creation.bytebuddy.TypeCaching

BytecodeGenerator

Using AI Code Generation

1import org.mockito.internal.creation.bytebuddy.BytecodeGenerator;2import org.mockito.internal.creation.bytebuddy.MockAccess;3import org.mockito.internal.creation.bytebuddy.MockMethodInterceptor;4import org.mockito.internal.util.MockUtil;5import org.mockito.invocation.MockHandler;6import org.mockito.mock.MockCreationSettings;7import org.mockito.plugins.MockMaker;8import java.lang.reflect.Constructor;9import java.lang.reflect.InvocationTargetException;10import java.lang.reflect.Method;11import java.lang.reflect.Modifier;12public class ByteBuddyMockMaker implements MockMaker {13    private static final String MOCKITO_MOCKS_PACKAGE = "org.mockito.codegen";14    private final BytecodeGenerator mockBytecodeGenerator = new BytecodeGenerator();15    private final BytecodeGenerator spyBytecodeGenerator = new BytecodeGenerator();16    public <T> T createMock(MockCreationSettings<T> settings, MockHandler handler) {17        Class<T> mockedType = settings.getTypeToMock();18        ClassLoader classLoader = mockedType.getClassLoader();19        boolean isInterface = mockedType.isInterface();20        String mockName = createMockName(settings);21        Class<?> mockClass = isInterface ? createInterfaceMockClass(mockName, settings) : createClassMockClass(mockName, settings);22        Constructor<?> constructor = findConstructor(mockClass);23        try {24            T mock = (T) constructor.newInstance(handler);25            MockAccess mockAccess = (MockAccess) mock;26            mockAccess.setMockitoInterceptor(new MockMethodInterceptor(handler));27            return mock;28        } catch (InstantiationException e) {29            throw new RuntimeException(e);30        } catch (IllegalAccessException e) {31            throw new RuntimeException(e);32        } catch (InvocationTargetException e) {33            throw new RuntimeException(e);34        }35    }36    private <T> String createMockName(MockCreationSettings<T> settings) {37        String name = MockUtil.getMockName(settings);38        if (name != null) {39            return name;40        }41        Class<T> type = settings.getTypeToMock();42        return type.getSimpleName();43    }44    private <T> Class<?> createClassMockClass(String mockName, MockCreationSettings<T> settings) {45        return mockBytecodeGenerator.mockClass(MOCKITO_MOCKS_PACKAGE, mockName, settings);46    }47    private <T> Class<?> createInterfaceMockClass(String mockName, MockCreationSettings<T> settings) {48        return mockBytecodeGenerator.mockInterface(MOCKITO_MOCKS

BytecodeGenerator

Using AI Code Generation

1public class 1 {2    public static void main(String[] args) {3        System.out.println("mocking a class and calling the method of the mocked class");4        BytecodeGenerator mockBytecodeGenerator = new BytecodeGenerator();5        Class<?> mockClass = mockBytecodeGenerator.mockClass(MockedClass.class);6        MockedClass mock = (MockedClass) mockBytecodeGenerator.mock(mockClass);7        mock.mockedMethod();8    }9}10public class 2 {11    public static void main(String[] args) {12        System.out.println("mocking a class and calling the method of the mocked class");13        ByteBuddyMockMaker mockMaker = new ByteBuddyMockMaker();14        MockedClass mock = (MockedClass) mockMaker.createMock(MockingSettingsImpl.mockSettings(MockedClass.class), new MockCreationValidator());15        mock.mockedMethod();16    }17}18public class 3 {19    public static void main(String[] args) {20        System.out.println("mocking a class and calling the method of the mocked class");21        ByteBuddyMockMaker mockMaker = new ByteBuddyMockMaker();22        MockedClass mock = (MockedClass) mockMaker.createMock(MockingSettings

Automation Testing Tutorials

Learn to execute automation testing from scratch with LambdaTest Learning Hub. Right from setting up the prerequisites to run your first automation test, to following best practices and diving deeper into advanced test scenarios. LambdaTest Learning Hubs compile a list of step-by-step guides to help you be proficient with different test automation frameworks i.e. Selenium, Cypress, TestNG etc.