org.robolectric.internal.bytecode.ShadowWrangler Maven / Gradle / Ivy
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package org.robolectric.internal.bytecode;
import static java.lang.invoke.MethodHandles.constant;
import static java.lang.invoke.MethodHandles.dropArguments;
import static java.lang.invoke.MethodHandles.foldArguments;
import static java.lang.invoke.MethodHandles.identity;
import static java.lang.invoke.MethodType.methodType;
import static org.robolectric.util.reflector.Reflector.reflector;
import com.google.auto.service.AutoService;
import com.google.errorprone.annotations.Keep;
import java.lang.invoke.MethodHandle;
import java.lang.invoke.MethodHandles;
import java.lang.invoke.MethodType;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Parameter;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import javax.annotation.Nonnull;
import javax.annotation.Priority;
import org.robolectric.annotation.ClassName;
import org.robolectric.annotation.Implementation;
import org.robolectric.annotation.RealObject;
import org.robolectric.annotation.ReflectorObject;
import org.robolectric.sandbox.ShadowMatcher;
import org.robolectric.util.Function;
import org.robolectric.util.PerfStatsCollector;
/**
* ShadowWrangler matches shadowed classes up with corresponding shadows based on a {@link
* ShadowMap}.
*
* ShadowWrangler has no specific knowledge of Android SDK levels or other peculiarities of the
* affected classes and shadows.
*
*
To apply additional rules about which shadow classes and methods are considered matches, pass
* in a {@link ShadowMatcher}.
*
*
ShadowWrangler is Robolectric's default {@link ClassHandler} implementation. To inject your
* own, create a subclass and annotate it with {@link AutoService}(ClassHandler).
*/
@SuppressWarnings("NewApi")
@AutoService(ClassHandler.class)
@Priority(Integer.MIN_VALUE)
public class ShadowWrangler implements ClassHandler {
public static final Function DO_NOTHING_HANDLER =
new Function() {
@Override
public Object call(Class theClass, Object value, Object[] params) {
return null;
}
};
public static final Method CALL_REAL_CODE = null;
public static final MethodHandle DO_NOTHING =
constant(Void.class, null).asType(methodType(void.class));
public static final Method DO_NOTHING_METHOD;
static {
try {
DO_NOTHING_METHOD = ShadowWrangler.class.getDeclaredMethod("doNothing");
DO_NOTHING_METHOD.setAccessible(true);
} catch (NoSuchMethodException e) {
throw new RuntimeException(e);
}
}
private static final MethodHandles.Lookup LOOKUP = MethodHandles.lookup();
private static final Class[] NO_ARGS = new Class[0];
static final Object NO_SHADOW = new Object();
private static final MethodHandle NO_SHADOW_HANDLE = constant(Object.class, NO_SHADOW);
private final ShadowMap shadowMap;
private final Interceptors interceptors;
private final ShadowMatcher shadowMatcher;
private final MethodHandle reflectorHandle;
/** key is instrumented class */
private final ClassValueMap cachedShadowInfos =
new ClassValueMap() {
@Override
protected ShadowInfo computeValue(Class type) {
return shadowMap.getShadowInfo(type, shadowMatcher);
}
};
/** key is shadow class */
private final ClassValueMap cachedShadowMetadata =
new ClassValueMap() {
@Nonnull
@Override
protected ShadowMetadata computeValue(Class type) {
return new ShadowMetadata(type);
}
};
public ShadowWrangler(
ShadowMap shadowMap, ShadowMatcher shadowMatcher, Interceptors interceptors) {
this.shadowMap = shadowMap;
this.shadowMatcher = shadowMatcher;
this.interceptors = interceptors;
try {
this.reflectorHandle =
LOOKUP
.findVirtual(
ShadowWrangler.class,
"injectReflectorObjectOn",
methodType(void.class, Object.class, Object.class))
.bindTo(this);
} catch (IllegalAccessException | NoSuchMethodException e) {
throw new RuntimeException(
"Could not instantiate MethodHandle for ReflectorObject injection.", e);
}
}
@SuppressWarnings("ReferenceEquality")
@Override
public void classInitializing(Class clazz) {
try {
Method method =
pickShadowMethod(clazz, ShadowConstants.STATIC_INITIALIZER_METHOD_NAME, NO_ARGS);
// if we got back DO_NOTHING_METHOD that means the shadow is {@code callThroughByDefault =
// false};
// for backwards compatibility we'll still perform static initialization though for now.
if (method == DO_NOTHING_METHOD) {
method = null;
}
if (method != null) {
if (!Modifier.isStatic(method.getModifiers())) {
throw new RuntimeException(
method.getDeclaringClass().getName() + "." + method.getName() + " is not static");
}
method.invoke(null);
} else {
RobolectricInternals.performStaticInitialization(clazz);
}
} catch (InvocationTargetException | IllegalAccessException e) {
throw new RuntimeException(e);
}
}
@SuppressWarnings({"ReferenceEquality"})
@Override
public MethodHandle findShadowMethodHandle(
Class definingClass,
String name,
MethodType methodType,
boolean isStatic,
boolean isNative)
throws IllegalAccessException {
return PerfStatsCollector.getInstance()
.measure(
"find shadow method handle",
() -> {
MethodType actualType = isStatic ? methodType : methodType.dropParameterTypes(0, 1);
Class[] paramTypes = actualType.parameterArray();
Method shadowMethod = pickShadowMethod(definingClass, name, paramTypes);
if (shadowMethod == CALL_REAL_CODE) {
ShadowInfo shadowInfo = getExactShadowInfo(definingClass);
if (isNative && shadowInfo != null && shadowInfo.callNativeMethodsByDefault) {
try {
Method method =
definingClass.getDeclaredMethod(
ShadowConstants.ROBO_PREFIX + name + "$nativeBinding", paramTypes);
method.setAccessible(true);
return LOOKUP.unreflect(method);
} catch (NoSuchMethodException e) {
throw new LinkageError("Missing native binding method", e);
}
}
return null;
} else if (shadowMethod == DO_NOTHING_METHOD) {
return DO_NOTHING;
}
shadowMethod.setAccessible(true);
MethodHandle mh;
if (name.equals(ShadowConstants.CONSTRUCTOR_METHOD_NAME)) {
if (Modifier.isStatic(shadowMethod.getModifiers())) {
throw new UnsupportedOperationException(
"static __constructor__ shadow methods are not supported");
}
// Use invokespecial to call constructor shadow methods. If invokevirtual is used,
// the wrong constructor may be called in situations where constructors with
// identical signatures are shadowed in object hierarchies.
mh =
MethodHandles.privateLookupIn(shadowMethod.getDeclaringClass(), LOOKUP)
.unreflectSpecial(shadowMethod, shadowMethod.getDeclaringClass());
} else {
mh = LOOKUP.unreflect(shadowMethod);
}
// Robolectric doesn't actually look for static, this for example happens
// in MessageQueue.nativeInit() which used to be void non-static in 4.2.
if (!isStatic && Modifier.isStatic(shadowMethod.getModifiers())) {
return dropArguments(mh, 0, Object.class);
} else {
return mh;
}
});
}
/**
* Return a method handle of the shadow class which matches the given function signature of the
* shadowed class.
*
* @param definingClass The shadowed class
* @param name The name of the method
* @param paramTypes The parameter list of the method
* @return A method handle of the corresponding shadow class
*/
protected Method pickShadowMethod(Class definingClass, String name, Class[] paramTypes) {
ShadowInfo shadowInfo = getExactShadowInfo(definingClass);
if (shadowInfo == null) {
return CALL_REAL_CODE;
} else {
ClassLoader classLoader = definingClass.getClassLoader();
Class shadowClass;
try {
shadowClass = Class.forName(shadowInfo.shadowClassName, false, classLoader);
} catch (ClassNotFoundException e) {
throw new IllegalStateException(e);
}
Method method = findShadowMethod(definingClass, name, paramTypes, shadowInfo, shadowClass);
if (method == null) {
return shadowInfo.callThroughByDefault ? CALL_REAL_CODE : DO_NOTHING_METHOD;
} else {
return method;
}
}
}
/**
* Searches for an {@code @Implementation} method on a given shadow class.
*
* If the shadow class allows loose signatures, search for them.
*
*
If the shadow class has function using @ClassName matches the requirement, return it
*
*
If the shadow class doesn't have such a method, but does have a superclass which implements
* the same class as it, call ourself recursively with the shadow superclass.
*/
private Method findShadowMethod(
Class definingClass,
String name,
Class[] types,
ShadowInfo shadowInfo,
Class shadowClass) {
Method method =
findShadowMethodDeclaredOnClass(shadowClass, name, types, shadowInfo.looseSignatures);
if (method != null) {
return method;
} else {
// if the shadow's superclass shadows the same class as this shadow, then recurse.
// Buffalo buffalo buffalo buffalo buffalo buffalo buffalo.
Class shadowSuperclass = shadowClass.getSuperclass();
if (shadowSuperclass != null && !shadowSuperclass.equals(Object.class)) {
ShadowInfo shadowSuperclassInfo = ShadowMap.obtainShadowInfo(shadowSuperclass, true);
if (shadowSuperclassInfo != null
&& shadowSuperclassInfo.isShadowOf(definingClass)
&& shadowMatcher.matches(shadowSuperclassInfo)) {
method =
findShadowMethod(definingClass, name, types, shadowSuperclassInfo, shadowSuperclass);
}
}
}
return method;
}
private Method findShadowMethodDeclaredOnClass(
Class shadowClass, String methodName, Class[] paramClasses, boolean looseSignatures) {
Method foundMethod = null;
// Try to find shadow method with exact method name and looseSignature.
Method[] methods = shadowClass.getDeclaredMethods();
for (Method method : methods) {
if (!method.getName().equals(methodName)
|| method.getParameterCount() != paramClasses.length) {
continue;
}
if (!Modifier.isPublic(method.getModifiers())
&& !Modifier.isProtected(method.getModifiers())) {
continue;
}
if (!shadowMatcher.matches(method)) {
continue;
}
if (Arrays.equals(method.getParameterTypes(), paramClasses)) {
// Found an exact match, we can exit early.
foundMethod = method;
break;
}
if (looseSignatures) {
boolean allParameterTypesAreObject = true;
for (Class paramClass : method.getParameterTypes()) {
if (!paramClass.equals(Object.class)) {
allParameterTypesAreObject = false;
break;
}
}
if (allParameterTypesAreObject) {
// Found a looseSignatures match, but continue looking for an exact match.
foundMethod = method;
}
} else {
// Or maybe support @ClassName.
if (parameterClassNameMatch(method, paramClasses)) {
// Found a @ClassName match, but continue looking for an exact match.
foundMethod = method;
}
}
}
if (foundMethod == null) {
// Try to find shadow method with Implementation#methodName's mapping name
for (Method method : methods) {
Implementation implementation = method.getAnnotation(Implementation.class);
if (implementation == null) {
continue;
}
String mappedMethodName = implementation.methodName().trim();
if (mappedMethodName.isEmpty() || !mappedMethodName.equals(methodName)) {
continue;
}
if (!shadowMatcher.matches(method)) {
continue;
}
if (Arrays.equals(method.getParameterTypes(), paramClasses)
|| parameterClassNameMatch(method, paramClasses)) {
foundMethod = method;
break;
}
}
}
if (foundMethod != null) {
foundMethod.setAccessible(true);
return foundMethod;
} else {
return null;
}
}
/**
* Check whether the parameters (which could be @ClassName annotated) of the {@code method}
* matches {@code paramClasses}.
*/
private boolean parameterClassNameMatch(Method method, Class[] paramClasses) {
Parameter[] params = method.getParameters();
if (params.length != paramClasses.length) {
return false;
}
for (int i = 0; i < params.length; ++i) {
if (params[i].getType().equals(paramClasses[i])) {
continue;
}
if (!params[i].getType().equals(Object.class)) {
return false; // @ClassName only applicable to parameter of Object type
}
ClassName className = params[i].getAnnotation(ClassName.class);
if (className == null || !className.value().equals(paramClasses[i].getName())) {
return false;
}
}
return true;
}
@Override
public Object intercept(String signature, Object instance, Object[] params, Class theClass)
throws Throwable {
final MethodSignature methodSignature = MethodSignature.parse(signature);
return interceptors.getInterceptionHandler(methodSignature).call(theClass, instance, params);
}
@Override
public T stripStackTrace(T throwable) {
StackTraceElement[] elements = throwable.getStackTrace();
if (elements != null) {
List stackTrace = new ArrayList<>();
String previousClassName = null;
String previousMethodName = null;
String previousFileName = null;
for (StackTraceElement stackTraceElement : elements) {
String methodName = stackTraceElement.getMethodName();
String className = stackTraceElement.getClassName();
String fileName = stackTraceElement.getFileName();
if (methodName.equals(previousMethodName)
&& className.equals(previousClassName)
&& fileName != null
&& fileName.equals(previousFileName)
&& stackTraceElement.getLineNumber() < 0) {
continue;
}
if (methodName.startsWith(ShadowConstants.ROBO_PREFIX)) {
methodName =
methodName.substring(
methodName.indexOf('$', ShadowConstants.ROBO_PREFIX.length() + 1) + 1);
stackTraceElement =
new StackTraceElement(
className,
methodName,
stackTraceElement.getFileName(),
stackTraceElement.getLineNumber());
}
if (className.startsWith("sun.reflect.") || className.startsWith("java.lang.reflect.")) {
continue;
}
stackTrace.add(stackTraceElement);
previousClassName = className;
previousMethodName = methodName;
previousFileName = fileName;
}
throwable.setStackTrace(stackTrace.toArray(new StackTraceElement[stackTrace.size()]));
}
return throwable;
}
private ShadowMetadata getShadowMetadata(Class shadowClass) {
return cachedShadowMetadata.get(shadowClass);
}
@Override
public MethodHandle getShadowCreator(Class theClass) {
ShadowInfo shadowInfo = getShadowInfo(theClass);
if (shadowInfo == null) return dropArguments(NO_SHADOW_HANDLE, 0, theClass);
String shadowClassName = shadowInfo.shadowClassName;
try {
Class shadowClass = Class.forName(shadowClassName, false, theClass.getClassLoader());
ShadowMetadata shadowMetadata = getShadowMetadata(shadowClass);
MethodHandle mh = identity(shadowClass); // (instance)
mh = dropArguments(mh, 1, theClass); // (instance)
for (Field field : shadowMetadata.realObjectFields) {
MethodHandle setter = LOOKUP.unreflectSetter(field);
MethodType setterType = mh.type().changeReturnType(void.class);
mh = foldArguments(mh, setter.asType(setterType));
}
MethodHandle classHandle =
reflectorHandle.asType(
reflectorHandle
.type()
.changeParameterType(0, shadowClass)
.changeParameterType(1, theClass));
mh = foldArguments(mh, classHandle);
mh =
foldArguments(
mh, LOOKUP.unreflectConstructor(shadowMetadata.constructor)); // (shadow, instance)
return mh; // (instance)
} catch (IllegalAccessException | ClassNotFoundException e) {
throw new RuntimeException(
"Could not instantiate shadow " + shadowClassName + " for " + theClass, e);
}
}
@Keep // This method is looked up using reflection.
private void injectReflectorObjectOn(Object shadow, Object instance) {
ShadowMetadata shadowMetadata = getShadowMetadata(shadow.getClass());
for (Field reflectorObjectField : shadowMetadata.reflectorObjectFields) {
setField(shadow, reflector(reflectorObjectField.getType(), instance), reflectorObjectField);
}
}
private ShadowInfo getShadowInfo(Class clazz) {
ShadowInfo shadowInfo = null;
for (; shadowInfo == null && clazz != null; clazz = clazz.getSuperclass()) {
shadowInfo = getExactShadowInfo(clazz);
}
return shadowInfo;
}
private ShadowInfo getExactShadowInfo(Class clazz) {
return cachedShadowInfos.get(clazz);
}
private static void setField(Object target, Object value, Field realObjectField) {
try {
realObjectField.set(target, value);
} catch (IllegalAccessException e) {
throw new RuntimeException(e);
}
}
private static class ShadowMetadata {
final Constructor constructor;
final List realObjectFields = new ArrayList<>();
final List reflectorObjectFields = new ArrayList<>();
public ShadowMetadata(Class shadowClass) {
try {
this.constructor = shadowClass.getConstructor();
} catch (NoSuchMethodException e) {
throw new RuntimeException("Missing public empty constructor on " + shadowClass, e);
}
while (shadowClass != null) {
for (Field field : shadowClass.getDeclaredFields()) {
if (field.isAnnotationPresent(RealObject.class)) {
if (Modifier.isStatic(field.getModifiers())) {
String message = "@RealObject must be on a non-static field, " + shadowClass;
System.err.println(message);
throw new IllegalArgumentException(message);
}
field.setAccessible(true);
realObjectFields.add(field);
}
if (field.isAnnotationPresent(ReflectorObject.class)) {
if (Modifier.isStatic(field.getModifiers())) {
String message = "@ReflectorObject must be on a non-static field, " + shadowClass;
System.err.println(message);
throw new IllegalArgumentException(message);
}
field.setAccessible(true);
reflectorObjectFields.add(field);
}
}
shadowClass = shadowClass.getSuperclass();
}
}
}
@SuppressWarnings("unused")
private static void doNothing() {}
}