org.mockito.internal.creation.jmock.ClassImposterizer Maven / Gradle / Ivy
/*
* Copyright (c) 2007 Mockito contributors
* This program is made available under the terms of the MIT License.
*/
package org.mockito.internal.creation.jmock;
import java.lang.reflect.*;
import java.util.List;
import org.mockito.cglib.core.*;
import org.mockito.cglib.proxy.*;
import org.mockito.exceptions.base.MockitoException;
import org.mockito.internal.creation.cglib.MockitoNamingPolicy;
import org.objenesis.ObjenesisStd;
/**
* Thanks to jMock guys for this handy class that wraps all the cglib magic.
*/
public class ClassImposterizer {
public static final ClassImposterizer INSTANCE = new ClassImposterizer();
private ClassImposterizer() {}
//TODO: after 1.8, in order to provide decent exception message when objenesis is not found,
//have a constructor in this class that tries to instantiate ObjenesisStd and if it fails then show decent exception that dependency is missing
//TODO: after 1.8, for the same reason catch and give better feedback when hamcrest core is not found.
private ObjenesisStd objenesis = new ObjenesisStd();
private static final NamingPolicy NAMING_POLICY_THAT_ALLOWS_IMPOSTERISATION_OF_CLASSES_IN_SIGNED_PACKAGES = new MockitoNamingPolicy() {
@Override
public String getClassName(String prefix, String source, Object key, Predicate names) {
return "codegen." + super.getClassName(prefix, source, key, names);
}
};
private static final CallbackFilter IGNORE_BRIDGE_METHODS = new CallbackFilter() {
public int accept(Method method) {
return method.isBridge() ? 1 : 0;
}
};
public boolean canImposterise(Class type) {
return !type.isPrimitive() && !Modifier.isFinal(type.getModifiers());
}
public T imposterise(final MethodInterceptor interceptor, Class mockedType, Class... ancillaryTypes) {
try {
setConstructorsAccessible(mockedType, true);
Class proxyClass = createProxyClass(mockedType, ancillaryTypes);
return mockedType.cast(createProxy(proxyClass, interceptor));
} finally {
setConstructorsAccessible(mockedType, false);
}
}
private void setConstructorsAccessible(Class mockedType, boolean accessible) {
for (Constructor constructor : mockedType.getDeclaredConstructors()) {
constructor.setAccessible(accessible);
}
}
private Class createProxyClass(Class mockedType, Class...interfaces) {
if (mockedType == Object.class) {
mockedType = ClassWithSuperclassToWorkAroundCglibBug.class;
}
Enhancer enhancer = new Enhancer() {
@Override
@SuppressWarnings("unchecked")
protected void filterConstructors(Class sc, List constructors) {
// Don't filter
}
};
enhancer.setClassLoader(SearchingClassLoader.combineLoadersOf(mockedType));
enhancer.setUseFactory(true);
if (mockedType.isInterface()) {
enhancer.setSuperclass(Object.class);
enhancer.setInterfaces(prepend(mockedType, interfaces));
} else {
enhancer.setSuperclass(mockedType);
enhancer.setInterfaces(interfaces);
}
enhancer.setCallbackTypes(new Class[]{MethodInterceptor.class, NoOp.class});
enhancer.setCallbackFilter(IGNORE_BRIDGE_METHODS);
if (mockedType.getSigners() != null) {
enhancer.setNamingPolicy(NAMING_POLICY_THAT_ALLOWS_IMPOSTERISATION_OF_CLASSES_IN_SIGNED_PACKAGES);
} else {
enhancer.setNamingPolicy(MockitoNamingPolicy.INSTANCE);
}
try {
return enhancer.createClass();
} catch (CodeGenerationException e) {
if (Modifier.isPrivate(mockedType.getModifiers())) {
throw new MockitoException("\n"
+ "Mockito cannot mock this class: " + mockedType
+ ".\n"
+ "Most likely it is a private class that is not visible by Mockito");
}
throw new MockitoException("\n"
+ "Mockito cannot mock this class: " + mockedType
+ "\n"
+ "Mockito can only mock visible & non-final classes."
+ "\n"
+ "If you're not sure why you're getting this error, please report to the mailing list.", e);
}
}
private Object createProxy(Class proxyClass, final MethodInterceptor interceptor) {
Factory proxy = (Factory) objenesis.newInstance(proxyClass);
proxy.setCallbacks(new Callback[] {interceptor, SerializableNoOp.SERIALIZABLE_INSTANCE });
return proxy;
}
private Class[] prepend(Class first, Class... rest) {
Class[] all = new Class[rest.length+1];
all[0] = first;
System.arraycopy(rest, 0, all, 1, rest.length);
return all;
}
public static class ClassWithSuperclassToWorkAroundCglibBug {}
}