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How to use transform method of org.powermock.modules.agent.PowerMockClassTransformer class

Best Powermock code snippet using org.powermock.modules.agent.PowerMockClassTransformer.transform

Source:PowerMockClassTransformer.java

...17package org.powermock.modules.agent;18import javassist.ClassPool;19import javassist.CtClass;20import org.powermock.core.agent.JavaAgentClassRegister;21import org.powermock.core.transformers.ClassWrapper;22import org.powermock.core.transformers.ClassWrapperFactory;23import org.powermock.core.transformers.MockTransformerChain;24import org.powermock.core.transformers.TransformStrategy;25import org.powermock.core.transformers.javassist.JavassistMockTransformerChainFactory;26import org.powermock.core.transformers.javassist.support.JavaAssistClassWrapperFactory;27import java.io.ByteArrayInputStream;28import java.io.IOException;29import java.lang.instrument.ClassFileTransformer;30import java.lang.instrument.IllegalClassFormatException;31import java.security.ProtectionDomain;32import java.util.Collection;33import java.util.HashSet;34import java.util.Set;35class PowerMockClassTransformer extends AbstractClassTransformer implements ClassFileTransformer {36    37    private static final MockTransformerChain MOCK_TRANSFORMER_CHAIN = new JavassistMockTransformerChainFactory()38                                                                           .createDefaultChain(TransformStrategy.INST_REDEFINE);39    private final ClassWrapperFactory wrapperFactory;40    private volatile Set<String> classesToTransform;41    private volatile JavaAgentClassRegister javaAgentClassRegister;42    43    PowerMockClassTransformer() {44        super();45        wrapperFactory = new JavaAssistClassWrapperFactory();46    }47    48    public void setClassesToTransform(Collection<String> classesToTransform) {49        this.classesToTransform = new HashSet<String>(classesToTransform);50    }51    52    public void setJavaAgentClassRegister(JavaAgentClassRegister javaAgentClassRegister) {53        this.javaAgentClassRegister = javaAgentClassRegister;54    }55    56    public byte[] transform(57                               ClassLoader loader, String className,58                               Class<?> classBeingRedefined, ProtectionDomain protectionDomain, byte[] classfileBuffer59    ) throws IllegalClassFormatException {60        61        if (loader == null || shouldIgnore(className)) {62            return null;63        }64        try {65            String normalizedClassName = className.replace("/", ".");66            if (classesToTransform != null && classesToTransform.contains(normalizedClassName)) {67                CtClass ctClass = getCtClass(classfileBuffer);68                69                ctClass = transform(ctClass);70                /*71                 * ClassPool may cause huge memory consumption if the number of CtClass72                 * objects becomes amazingly large (this rarely happens since Javassist73                 * tries to reduce memory consumption in various ways). To avoid this74                 * problem, you can explicitly remove an unnecessary CtClass object from75                 * the ClassPool. If you call detach() on a CtClass object, then that76                 * CtClass object is removed from the ClassPool.77                 */78                ctClass.detach();79                80                javaAgentClassRegister.registerClass(loader, normalizedClassName);81                82                return ctClass.toBytecode();83            }84            85            return null;86        } catch (Exception e) {87            throw new RuntimeException("Failed to redefine class " + className, e);88        }89    }90    91    private CtClass getCtClass(final byte[] classfileBuffer) throws IOException {92        final CtClass ctClass;93        94        ByteArrayInputStream is = new ByteArrayInputStream(classfileBuffer);95        try {96            ctClass = ClassPool.getDefault().makeClass(is);97        } finally {98            is.close();99        }100        return ctClass;101    }102    103    private CtClass transform(CtClass ctClass) throws Exception {104        ClassWrapper<CtClass> wrapped = wrapperFactory.wrap(ctClass);105        wrapped = MOCK_TRANSFORMER_CHAIN.transform(wrapped);106        return wrapped.unwrap();107    }108}...

transform

Using AI Code Generation

1public class PowerMockClassTransformerTest {2    private PowerMockClassTransformer transformer = new PowerMockClassTransformer();3    public void testTransform() throws Exception {4        byte[] bytes = transformer.transform(null, "org.powermock.core.classloader.MockClassLoader",5null, null, null);6        assertThat(bytes, notNullValue());7    }8}9	at org.powermock.modules.agent.PowerMockClassTransformer.transform(PowerMockClassTransformer.java:82)10	at org.powermock.modules.agent.PowerMockClassTransformerTest.testTransform(PowerMockClassTransformerTest.java:13)

transform

Using AI Code Generation

1import org.powermock.modules.agent.PowerMockClassTransformer;2import org.powermock.modules.agent.support.internal.impl.JavaAgentClassFileTransformer;3public class TestClass {4    public static void main(String[] args) {5        PowerMockClassTransformer transformer = new PowerMockClassTransformer();6        JavaAgentClassFileTransformer transformer1 = new JavaAgentClassFileTransformer();7        transformer1.transform(null, null, null, null, null);8    }9}10    at TestClass.main(TestClass.java:8)11    at java.net.URLClassLoader.findClass(URLClassLoader.java:381)12    at java.lang.ClassLoader.loadClass(ClassLoader.java:424)13    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:331)14    at java.lang.ClassLoader.loadClass(ClassLoader.java:357)15OpenJDK Runtime Environment (build 1.8.0_232-8u232-b09-0ubuntu1~16.04.1-b09)16OpenJDK 64-Bit Server VM (build 25.232-b09, mixed mode)

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