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How to use transform method of org.powermock.core.classloader.MockClassLoaderTest class

Best Powermock code snippet using org.powermock.core.classloader.MockClassLoaderTest.transform

Source:MockClassLoaderTest.java

...30import org.powermock.core.classloader.annotations.UseClassPathAdjuster;31import org.powermock.core.classloader.javassist.ClassPathAdjuster;32import org.powermock.core.classloader.javassist.JavassistMockClassLoader;33import org.powermock.core.test.MockClassLoaderFactory;34import org.powermock.core.transformers.ClassWrapper;35import org.powermock.core.transformers.MockTransformer;36import org.powermock.core.transformers.MockTransformerChain;37import org.powermock.core.transformers.support.DefaultMockTransformerChain;38import org.powermock.reflect.Whitebox;39@RunWith(Parameterized.class)40public class MockClassLoaderTest {41    private final MockClassLoaderFactory mockClassLoaderFactory;42    private final Class<? extends MockClassLoader> clazz;43    private final MockTransformerChain mockTransformerChain;44    public MockClassLoaderTest(Class<? extends MockClassLoader> clazz, MockTransformer transformer) {45        this.mockClassLoaderFactory = new MockClassLoaderFactory(clazz);46        this.clazz = clazz;47        this.mockTransformerChain = DefaultMockTransformerChain.newBuilder().append(transformer).build();48    }49    @Test50    public void should_load_and_modify_class_from_package_which_specified() throws Exception {51        String className = "powermock.test.support.ClassForMockClassLoaderTestCase";52        MockClassLoader mockClassLoader = mockClassLoaderFactory.getInstance(new String[]{ className });53        mockClassLoader.setMockTransformerChain(mockTransformerChain);54        Class<?> clazz = Class.forName(className, false, mockClassLoader);55        assertClassIsLoaded(clazz, mockClassLoader);56        assertThatInstanceCouldBeCreateAndMethodReturnMockedValue(clazz);57    }58    @Test59    public void should_load_and_not_modify_class_from_package_which_are_not_specified_as_ignored_or_class_to_mock() throws Exception {60        String className = "powermock.test.support.ClassForMockClassLoaderTestCase";61        MockClassLoader mockClassLoader = mockClassLoaderFactory.getInstance(new String[0]);62        mockClassLoader.setMockTransformerChain(mockTransformerChain);63        Class<?> clazz = Class.forName(className, false, mockClassLoader);64        assertClassIsLoaded(clazz, mockClassLoader);65        assertThatInstanceCouldBeCreateAndMethodReturnNotMockedValue(clazz);66    }67    @Test68    public void should_load_system_classes() throws Exception {69        MockClassLoader mockClassLoader = mockClassLoaderFactory.getInstance(new String[]{ "org.mytest.myclass" });70        Class<?> clazz = Class.forName("java.lang.String", false, mockClassLoader);71        assertThat(clazz).as("System class is loaded").isEqualTo(String.class);72    }73    @Test74    public void should_load_defined_class() throws Exception {75        final String className = "my.ABCTestClass";76        final MockClassLoader mockClassLoader = mockClassLoaderFactory.getInstance(new String[]{ className });77        Whitebox.invokeMethod(mockClassLoader, "defineClass", className, MockClassLoaderTest.DynamicClassHolder.classBytes, 0, MockClassLoaderTest.DynamicClassHolder.classBytes.length, this.getClass().getProtectionDomain());78        Class<?> clazz = Class.forName(className, false, mockClassLoader);79        assertThat(clazz).as("Defined class is loaded").isNotNull();80    }81    @Test82    public void should_ignore_pagackage_added_powerMockIgnore_Annotated() throws Exception {83        MockClassLoader mockClassLoader = mockClassLoaderFactory.getInstance(new String[]{ "org.ikk.Jux" });84        MockClassLoaderConfiguration configuration = mockClassLoader.getConfiguration();85        Whitebox.setInternalState(configuration, "deferPackages", new String[]{ "*mytest*" }, MockClassLoaderConfiguration.class);86        Assert.assertFalse(configuration.shouldModify("org.mytest.myclass"));87    }88    @Test89    public void powerMockIgnoreAnnotatedPackagesHavePrecedenceOverPrepareEverythingForTest() throws Exception {90        MockClassLoader mockClassLoader = mockClassLoaderFactory.getInstance(new String[]{ MockClassLoader.MODIFY_ALL_CLASSES });91        MockClassLoaderConfiguration configuration = mockClassLoader.getConfiguration();92        Whitebox.setInternalState(configuration, "deferPackages", new String[]{ "*mytest*" }, MockClassLoaderConfiguration.class);93        Assert.assertFalse(configuration.shouldModify("org.mytest.myclass"));94    }95    @Test96    public void should_find_and_return_a_one_resource_which_exist() throws Exception {97        final MockClassLoader mockClassLoader = mockClassLoaderFactory.getInstance(new String[0]);98        // Force a ClassLoader that can find 'foo/bar/baz/test.txt' into99        // mockClassLoader.deferTo.100        mockClassLoader.deferTo = new ResourcePrefixClassLoader(getClass().getClassLoader(), "org/powermock/core/classloader/");101        // MockClassLoader will only be able to find 'foo/bar/baz/test.txt' if it102        // properly defers the resource lookup to its deferTo ClassLoader.103        URL resource = mockClassLoader.getResource("foo/bar/baz/test.txt");104        assertThat(resource).isNotNull();105        assertThat(resource.getPath()).endsWith("test.txt");106    }107    @Test108    public void should_find_and_return_resources_which_exist() throws Exception {109        final MockClassLoader mockClassLoader = mockClassLoaderFactory.getInstance(new String[0]);110        // Force a ClassLoader that can find 'foo/bar/baz/test.txt' into111        // mockClassLoader.deferTo.112        mockClassLoader.deferTo = new ResourcePrefixClassLoader(getClass().getClassLoader(), "org/powermock/core/classloader/");113        // MockClassLoader will only be able to find 'foo/bar/baz/test.txt' if it114        // properly defers the resources lookup to its deferTo ClassLoader.115        Enumeration<URL> resources = mockClassLoader.getResources("foo/bar/baz/test.txt");116        assertThat(resources.nextElement().getPath()).endsWith("test.txt");117    }118    @Test119    public void resourcesNotDoubled() throws Exception {120        final MockClassLoader mockClassLoader = mockClassLoaderFactory.getInstance(new String[0]);121        // mockClassLoader.setMockTransformerChain(transformerChain);122        // MockClassLoader will only be able to find 'foo/bar/baz/test.txt' if it123        // properly defers the resources lookup to its deferTo ClassLoader.124        Enumeration<URL> resources = mockClassLoader.getResources("org/powermock/core/classloader/foo/bar/baz/test.txt");125        assertThat(resources.nextElement().getPath()).endsWith("test.txt");126        assertThat(resources.hasMoreElements()).isFalse();127    }128    @Test129    public void canFindDynamicClassFromAdjustedClasspath() throws Exception {130        Assume.assumeThat(clazz.getName(), CoreMatchers.equalTo(JavassistMockClassLoader.class.getName()));131        // Construct MockClassLoader with @UseClassPathAdjuster annotation.132        // It activates our MyClassPathAdjuster class which appends our dynamic133        // class to the MockClassLoader's classpool.134        UseClassPathAdjuster useClassPathAdjuster = new MockClassLoaderTest.TestUseClassPathAdjuster();135        final MockClassLoader mockClassLoader = mockClassLoaderFactory.getInstance(new String[0], useClassPathAdjuster);136        // setup custom classloader providing our dynamic class, for MockClassLoader to defer to137        mockClassLoader.deferTo = new ClassLoader(getClass().getClassLoader()) {138            @Override139            public Class<?> loadClass(String name) throws ClassNotFoundException {140                if (name.equals(MockClassLoaderTest.DynamicClassHolder.clazz.getName())) {141                    return MockClassLoaderTest.DynamicClassHolder.clazz;142                }143                return super.loadClass(name);144            }145        };146        // verify that MockClassLoader can successfully load the class147        Class<?> dynamicTestClass = Class.forName(MockClassLoaderTest.DynamicClassHolder.clazz.getName(), false, mockClassLoader);148        assertThat(dynamicTestClass).isNotSameAs(MockClassLoaderTest.DynamicClassHolder.clazz);149    }150    @Test151    public void should_autobox_primitive_values() throws Exception {152        String name = (this.getClass().getPackage().getName()) + ".HardToTransform";153        final MockClassLoader mockClassLoader = mockClassLoaderFactory.getInstance(new String[]{ name });154        Class<?> c = mockClassLoader.loadClass(name);155        Object object = c.newInstance();156        Whitebox.invokeMethod(object, "run");157        assertThat(5).isEqualTo(Whitebox.invokeMethod(object, "testInt"));158        assertThat(5L).isEqualTo(Whitebox.invokeMethod(object, "testLong"));159        assertThat(5.0F).isEqualTo(Whitebox.invokeMethod(object, "testFloat"));160        assertThat(5.0).isEqualTo(Whitebox.invokeMethod(object, "testDouble"));161        assertThat(new Short("5")).isEqualTo(Whitebox.invokeMethod(object, "testShort"));162        assertThat(new Byte("5")).isEqualTo(Whitebox.invokeMethod(object, "testByte"));163        assertThat(true).isEqualTo(Whitebox.invokeMethod(object, "testBoolean"));164        assertThat('5').isEqualTo(Whitebox.invokeMethod(object, "testChar"));165        assertThat("5").isEqualTo(Whitebox.invokeMethod(object, "testString"));166    }167    // helper class for canFindDynamicClassFromAdjustedClasspath()168    public static class MyClassPathAdjuster implements ClassPathAdjuster {169        public void adjustClassPath(ClassPool classPool) {170            classPool.appendClassPath(new ByteArrayClassPath(MockClassLoaderTest.DynamicClassHolder.clazz.getName(), MockClassLoaderTest.DynamicClassHolder.classBytes));171        }172    }173    // helper class for canFindDynamicClassFromAdjustedClasspath()174    static class DynamicClassHolder {175        static final byte[] classBytes;176        static final Class<?> clazz;177        static {178            try {179                // construct a new class dynamically180                ClassPool cp = ClassPool.getDefault();181                final CtClass ctClass = cp.makeClass("my.ABCTestClass");182                classBytes = ctClass.toBytecode();183                clazz = ctClass.toClass();184            } catch (Exception e) {185                throw new RuntimeException("Problem constructing custom class", e);186            }187        }188    }189    public static class TestUseClassPathAdjuster implements UseClassPathAdjuster {190        public Class<? extends Annotation> annotationType() {191            return UseClassPathAdjuster.class;192        }193        public Class<? extends ClassPathAdjuster> value() {194            return MockClassLoaderTest.MyClassPathAdjuster.class;195        }196    }197    private static class JavassistMockTransformer implements MockTransformer<CtClass> {198        @Override199        public ClassWrapper<CtClass> transform(final ClassWrapper<CtClass> clazz) throws Exception {200            CtClass ctClass = clazz.unwrap();201            for (CtMethod ctMethod : ctClass.getMethods()) {202                CtClass returnType = ctMethod.getReturnType();203                if (returnType.getName().equals(String.class.getName())) {204                    ctMethod.setBody("return null;");205                }206            }207            return clazz;208        }209    }210}...

transform

Using AI Code Generation

1package com.abc;2public class ClassToBeMocked {3    public String getString() {4        return "abc";5    }6}7package com.abc;8import org.junit.Test;9import org.junit.runner.RunWith;10import org.powermock.api.mockito.PowerMockito;11import org.powermock.core.classloader.MockClassLoader;12import org.powermock.core.classloader.annotations.PrepareForTest;13import org.powermock.modules.junit4.PowerMockRunner;14import static org.junit.Assert.assertEquals;15import static org.powermock.api.mockito.PowerMockito.when;16@RunWith(PowerMockRunner.class)17@PrepareForTest({MockClassLoader.class})18public class MockClassLoaderTest {19    public void testMockClassLoader() throws Exception {20        ClassToBeMocked mockedClass = PowerMockito.mock(ClassToBeMocked.class);21        when(mockedClass.getString()).thenReturn("xyz");22        assertEquals("xyz", mockedClass.getString());23        ClassToBeMocked classToBeMocked = (ClassToBeMocked) MockClassLoader.transform("com.abc.ClassToBeMocked");24        assertEquals("xyz", classToBeMocked.getString());25    }26}27    at org.junit.Assert.fail(Assert.java:88)28    at org.junit.Assert.failNotEquals(Assert.java:834)29    at org.junit.Assert.assertEquals(Assert.java:118)30    at org.junit.Assert.assertEquals(Assert.java:144)31    at com.abc.MockClassLoaderTest.testMockClassLoader(MockClassLoaderTest.java:24)32    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)33    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)34    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)35    at java.lang.reflect.Method.invoke(Method.java:498)36    at org.junit.runners.model.FrameworkMethod$1.runReflectiveCall(FrameworkMethod.java:50)37    at org.junit.internal.runners.model.ReflectiveCallable.run(ReflectiveCallable.java:12)38    at org.junit.runners.model.FrameworkMethod.invokeExplosively(FrameworkMethod.java:47)39    at org.junit.internal.runners.statements.InvokeMethod.evaluate(InvokeMethod.java:17)

transform

Using AI Code Generation

1    public void testTransform() throws Exception {2        final MockClassLoader mockClassLoader = new MockClassLoader();3        final Class<?> mockedClass = mockClassLoader.transform(MockClassLoaderTest.class.getClassLoader(), "org.powermock.core.classloader.MockClassLoaderTest$MockedClass");4        final Object instance = mockedClass.newInstance();5        assertThat(instance, notNullValue());6        assertThat(instance, instanceOf(MockedClass.class));7    }8}

transform

Using AI Code Generation

1import org.powermock.core.classloader.MockClassLoaderTest;2import org.powermock.core.classloader.MockClassLoaderTest$MockClass;3public class MockClassLoaderTest$MockClass {4    public static String mock() {5        return "mock";6    }7}8[INFO] --- maven-surefire-plugin:2.19.1:test (default-test) @ powermock-classloading-xstream ---

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