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How to use transform method of org.powermock.core.transformers.javassist.AbstractJavaAssistMockTransformer class

Best Powermock code snippet using org.powermock.core.transformers.javassist.AbstractJavaAssistMockTransformer.transform

Source:MockTransformerTestHelper.java

...14 *   See the License for the specific language governing permissions and15 *   limitations under the License.16 *17 */18package org.powermock.core.transformers;19import org.powermock.core.MockGateway;20import org.powermock.core.classloader.javassist.JavassistMockClassLoader;21import org.powermock.core.test.MockClassLoaderFactory;22import org.powermock.core.transformers.javassist.AbstractJavaAssistMockTransformer;23import org.powermock.core.transformers.support.DefaultMockTransformerChain;24import org.powermock.reflect.internal.WhiteboxImpl;25import java.lang.reflect.Constructor;26import java.lang.reflect.Field;27import java.util.ArrayList;28import java.util.Collection;29import java.util.List;30class MockTransformerTestHelper {31    32    static Collection<Object[]> createTransformerTestData(final Class<?>... transformerClass) {33        return createTransformerTestDataWithMockGateway(MockGateway.class, transformerClass);34    }35    36    static Collection<Object[]> createTransformerTestDataWithMockGateway(final Class<?> mockGateway, final Class<?>... transformerClass) {37        List<Object[]> data = new ArrayList<Object[]>();38        39        for (TransformStrategy strategy : TransformStrategy.values()) {40            List<MockTransformerChain> transformerChains = createTransformers(mockGateway, strategy, transformerClass);41            42            for (MockTransformerChain mockTransformer : transformerChains) {43                data.add(new Object[]{44                    strategy,45                    mockTransformer,46                    createClassLoaderFactory(transformerClass[0])47                });48            }49        }50        51        return data;52    }53    54    static Collection<Object[]> createOneTransformerTestData(final Class<?> transformerClass) {55        return createOneTransformerTestData(MockGateway.class, transformerClass);56    }57    58    static Collection<Object[]> createOneTransformerTestData(final Class<?> mockGateway, final Class<?> transformerClass) {59        List<Object[]> data = new ArrayList<Object[]>();60        61        for (TransformStrategy strategy : TransformStrategy.values()) {62            MockTransformer transformer = getInstance(mockGateway, strategy, transformerClass);63            64            data.add(new Object[]{65                strategy,66                transformer,67                createClassLoaderFactory(transformerClass)68            });69        }70        71        return data;72    }73    74    private static MockClassLoaderFactory createClassLoaderFactory(final Class<?> transformerClass) {75        if (AbstractJavaAssistMockTransformer.class.isAssignableFrom(transformerClass)){76            return new MockClassLoaderFactory(JavassistMockClassLoader.class);77        }78        throw new UnsupportedOperationException();79    }80    81    private static List<MockTransformerChain> createTransformers(final Class<?> mockGateway, final TransformStrategy strategy, final Class<?>... classes) {82        List<MockTransformerChain> transformers = new ArrayList<MockTransformerChain>();83        84        for (Class<?> transformerClass : classes) {85            MockTransformer transformer = getInstance(mockGateway, strategy, transformerClass);86            transformers.add(createChainFrom(transformer));87        }88        89        return transformers;90    }91    92    private static MockTransformer getInstance(final Class<?> mockGateway, final TransformStrategy strategy, final Class<?> transformerClass) {93        try {94            Constructor<?> constructor = transformerClass.getConstructor(TransformStrategy.class);95            Object instance = constructor.newInstance(strategy);96    97            Field mockGetawayClassField = null;98            try {99                mockGetawayClassField = WhiteboxImpl.getField(transformerClass, "mockGetawayClass");100            } catch (Exception e) {101                // do nothing102            }103    104            if (mockGetawayClassField != null){105                mockGetawayClassField.setAccessible(true);106                mockGetawayClassField.set(instance, mockGateway);107            }108    109            return (MockTransformer) instance;110        } catch (Exception e) {111            throw new RuntimeException("Cannot create an instance of transformer.", e);112        }113    }114    115    private static MockTransformerChain createChainFrom(final MockTransformer transformer) {116        return DefaultMockTransformerChain.newBuilder()117                                          .append(transformer)118                                          .build();119    }120}...

Source:AbstractJavaAssistMockTransformer.java

...14 *   See the License for the specific language governing permissions and15 *   limitations under the License.16 *17 */18package org.powermock.core.transformers.javassist;19import javassist.CtClass;20import org.powermock.core.transformers.ClassWrapper;21import org.powermock.core.transformers.MockTransformer;22import org.powermock.core.transformers.TransformStrategy;23public abstract class AbstractJavaAssistMockTransformer implements MockTransformer<CtClass> {24    25    private final TransformStrategy strategy;26    27    public AbstractJavaAssistMockTransformer(TransformStrategy strategy) {28        this.strategy = strategy;29    }30    31    @Override32    public ClassWrapper<CtClass> transform(final ClassWrapper<CtClass> clazz) throws Exception {33        if (clazz.unwrap() instanceof  CtClass) {34            CtClass classImpl = clazz.unwrap();35        36            if (classImpl != null) {37                transform(classImpl);38            }39        }40    41        return clazz;42    }43    44    public abstract CtClass transform(CtClass clazz) throws Exception;45    46    protected TransformStrategy getStrategy() {47        return strategy;48    }49}...

transform

Using AI Code Generation

1import java.io.File;2import java.io.IOException;3import java.io.InputStream;4import java.lang.reflect.InvocationTargetException;5import java.lang.reflect.Method;6import java.net.URL;7import java.net.URLClassLoader;8import java.util.ArrayList;9import java.util.List;10import org.powermock.core.transformers.javassist.AbstractJavaAssistMockTransformer;11public class ClassLoaderTest {12    public static void main(String[] args) throws IOException, ClassNotFoundException, NoSuchMethodException, SecurityException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {13        String classPath = "/home/vishal/Downloads/4.class";14        String className = "Test";15        ClassLoader classLoader = new URLClassLoader(new URL[] { new File(classPath).toURI().toURL() });16        Class<?> clazz = classLoader.loadClass(className);17        Method method = clazz.getDeclaredMethod("main", String[].class);18        method.invoke(null, new Object[] { new String[] {} });19    }20}21public class Test {22    public static void main(String[] args) {23        System.out.println("Hello World!");24    }25}26public class ArrayUtils {27    public static int[] findMaxMin(int[] array) {28        int max = array[0];29        int min = array[0];30        for (int i = 0; i < array.length; i++) {31            if (array[i] > max) {

transform

Using AI Code Generation

1import java.io.File;2import java.io.FileOutputStream;3import java.io.IOException;4import java.lang.instrument.IllegalClassFormatException;5import java.util.Arrays;6import java.util.List;7import org.powermock.core.transformers.MockTransformer;8import org.powermock.core.transformers.javassist.AbstractJavaAssistMockTransformer;9public class TestTransform extends AbstractJavaAssistMockTransformer {10	public TestTransform(MockTransformer... transformers) {11		super(transformers);12	}13	protected byte[] transformClass(ClassLoader loader, String className, byte[] classBeingRedefined, Class<?> classBeingRedefined2, byte[] classfileBuffer)14			throws IllegalClassFormatException {15		return super.transformClass(loader, className, classBeingRedefined, classBeingRedefined2, classfileBuffer);16	}17	public static void main(String[] args) throws Exception {18		byte[] classBytes = null;19		try {20			classBytes = org.apache.commons.io.FileUtils.readFileToByteArray(new File("C:\\Users\\Pankaj\\Desktop\\4.class"));21		} catch (IOException e) {22			e.printStackTrace();23		}24		TestTransform t = new TestTransform();25		byte[] bytes = t.transformClass(null, null, null, null, classBytes);26		FileOutputStream f = new FileOutputStream(new File("C:\\Users\\Pankaj\\Desktop\\4.class"));27		f.write(bytes);28		f.close();29	}30}31public class TestTransform {32	private int a;33	private String b;34	private List<String> c;35	private int[] d;36	private int[][] e;37	public TestTransform(int a, String b, List<String> c, int[] d, int[][] e) {38		super();39		this.a = a;40		this.b = b;41		this.c = c;42		this.d = d;43		this.e = e;44	}45	public int getA() {46		return a;47	}48	public void setA(int a) {49		this.a = a;50	}51	public String getB() {52		return b;53	}54	public void setB(String b) {55		this.b = b;56	}57	public List<String> getC() {58		return c;59	}60	public void setC(List<String> c) {61		this.c = c;62	}

transform

Using AI Code Generation

1package com.powermock;2import java.io.ByteArrayOutputStream;3import java.io.File;4import java.io.FileInputStream;5import java.io.FileNotFoundException;6import java.io.IOException;7import java.io.InputStream;8import java.util.List;9import org.powermock.core.transformers.javassist.AbstractJavaAssistMockTransformer;10public class Transformer {11    private static String classFile = "C:\\Users\\vishal\\Desktop\\4.class";12    private static String className = "com.powermock.HelloWorld";13    public static void main(String[] args) throws IOException {14        Transformer transformer = new Transformer();15        transformer.transform();16    }17    public void transform() throws IOException {18        byte[] classBytes = getClassBytes();19        AbstractJavaAssistMockTransformer mockTransformer = new AbstractJavaAssistMockTransformer() {20            protected List<String> getFullyQualifiedNamesOfClassesToTransform() {21                return null;22            }23            protected String transformClass(String className, String classBeingRedefined,24                    throws Exception {25                return "public class " + className + " { public String sayHello() { return \"Hello World!\"; } }";26            }27        };28        byte[] transformedClassBytes = mockTransformer.transform(classBytes, className);29        System.out.println(transformedClassBytes);30    }31    private byte[] getClassBytes() throws IOException {32        File file = new File(classFile);33        InputStream inputStream = new FileInputStream(file);34        ByteArrayOutputStream outputStream = new ByteArrayOutputStream();35        int nextValue = inputStream.read();36        while (-1 != nextValue) {37            outputStream.write(nextValue);38            nextValue = inputStream.read();39        }40        return outputStream.toByteArray();41    }42}

transform

Using AI Code Generation

1import java.lang.instrument.ClassFileTransformer;2import java.security.ProtectionDomain;3import javassist.ClassPool;4import javassist.CtClass;5import javassist.CtMethod;6import org.powermock.core.transformers.javassist.AbstractJavaAssistMockTransformer;7public class AddMethodTransformer extends AbstractJavaAssistMockTransformer implements ClassFileTransformer {8    public byte[] transform(ClassLoader loader, String className, Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] classfileBuffer) throws Exception {9        ClassPool classPool = ClassPool.getDefault();10        CtClass ctClass = classPool.get(className.replace('/', '.'));11        CtMethod ctMethod = CtMethod.make("public void newMethod() { System.out.println(\"new method\"); }", ctClass);12        ctClass.addMethod(ctMethod);13        return ctClass.toBytecode();14    }15}16import java.lang.reflect.Method;17public class TestClass {18    public static void main(String[] args) throws Exception {19        ClassLoader cl = new ClassLoader() {20            public Class<?> loadClass(String name) throws ClassNotFoundException {21                if (name.equals("MyClass")) {22                    return super.defineClass(name, new AddMethodTransformer().transform(null, name, null, null, new MyClass().getBytes()), 0, new MyClass().getBytes().length);23                }24                return super.loadClass(name);25            }26        };27        Class<?> c = cl.loadClass("MyClass");28        Object o = c.newInstance();29        Method m = c.getMethod("newMethod");30        m.invoke(o);31    }32}33public class MyClass {34    public void myMethod() {35        System.out.println("my method");36    }37}

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