Some refactor of Reflect class

This commit is contained in:
Marc Baloup 2022-02-07 12:42:14 +01:00
parent 66cbf8097c
commit 774b5f9e47

View File

@ -12,8 +12,6 @@ import java.util.Map;
import java.util.Objects;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.TimeUnit;
import java.util.function.Consumer;
import java.util.function.Predicate;
import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
@ -106,7 +104,7 @@ public class Reflect {
public static class ReflectClass<T> {
private Class<T> clazz;
private final Class<T> clazz;
private final Map<MethodIdentifier, ReflectMethod<T>> methodCache = Collections.synchronizedMap(new HashMap<>());
private final Map<ConstructorIdentifier, ReflectConstructor<T>> constructorCache = Collections.synchronizedMap(new HashMap<>());
@ -116,24 +114,62 @@ public class Reflect {
this.clazz = clazz;
}
private ReflectMethod<T> method(MethodIdentifier key) {
return methodCache.computeIfAbsent(key, k -> new ReflectMethod<>(this, k));
/**
* Returns the class wrapped by this ReflectClass instance.
*/
public Class<T> get() {
return clazz;
}
public ReflectMethod<T> method(String name, Class<?>... paramTypes) {
return method(new MethodIdentifier(name, paramTypes));
private ReflectMethod<T> method(MethodIdentifier key, boolean bypassFilter) throws NoSuchMethodException {
ReflectMethod<T> method = methodCache.get(key);
if (method == null) {
method = new ReflectMethod<>(this, key, bypassFilter);
methodCache.put(key, method);
}
return method;
}
private ReflectConstructor<T> constructor(ConstructorIdentifier key) {
return constructorCache.computeIfAbsent(key, k -> new ReflectConstructor<>(this, k));
public ReflectMethod<T> method(String name, Class<?>... paramTypes) throws NoSuchMethodException {
return method(new MethodIdentifier(name, paramTypes), false);
}
public ReflectConstructor<T> constructor(Class<?>... paramTypes) {
return constructor(new ConstructorIdentifier(paramTypes));
public ReflectMethod<T> filteredMethod(String name, Class<?>... paramTypes) throws NoSuchMethodException {
return method(new MethodIdentifier(name, paramTypes), true);
}
public ReflectField<T> field(String name) {
return fieldCache.computeIfAbsent(name, n -> new ReflectField<>(this, n));
private ReflectConstructor<T> constructor(ConstructorIdentifier key, boolean bypassFilter) throws NoSuchMethodException {
ReflectConstructor<T> constructor = constructorCache.get(key);
if (constructor == null) {
constructor = new ReflectConstructor<>(this, key, bypassFilter);
constructorCache.put(key, constructor);
}
return constructor;
}
public ReflectConstructor<T> constructor(Class<?>... paramTypes) throws NoSuchMethodException {
return constructor(new ConstructorIdentifier(paramTypes), false);
}
public ReflectConstructor<T> filteredConstructor(Class<?>... paramTypes) throws NoSuchMethodException {
return constructor(new ConstructorIdentifier(paramTypes), true);
}
private ReflectField<T> field0(String name, boolean bypassFilter) throws NoSuchFieldException {
ReflectField<T> constructor = fieldCache.get(name);
if (constructor == null) {
constructor = new ReflectField<>(this, name, bypassFilter);
fieldCache.put(name, constructor);
}
return constructor;
}
public ReflectField<T> field(String name) throws NoSuchFieldException {
return field0(name, false);
}
public ReflectField<T> filteredField(String name) throws NoSuchFieldException {
return field0(name, true);
}
}
@ -159,45 +195,127 @@ public class Reflect {
public static abstract class ReflectClassEl<T> {
public static abstract class ReflectMember<T, EL, EX extends ReflectiveOperationException> {
ReflectClass<T> reflectClass;
protected EL cached;
protected ReflectClassEl(ReflectClass<T> c) {
protected ReflectMember(ReflectClass<T> c, boolean bypassFilter) throws EX {
reflectClass = c;
cached = (bypassFilter) ? fetchFiltered() : get();
}
protected EL fetch() throws EX {
EX ex = null;
// get element in current class
try {
EL el = fetchFromClass(reflectClass.clazz);
setAccessible(el);
return el;
} catch (ReflectiveOperationException e) {
@SuppressWarnings("unchecked")
EX ee = (EX) e;
ex = ee;
}
// get parent class
Class<? super T> superClass = reflectClass.clazz.getSuperclass();
if (superClass == null)
throw ex;
// get element in parent class (will do recursion)
try {
EL el = fetchFromReflectClass(ofClass(superClass));
setAccessible(el);
return el;
} catch (ReflectiveOperationException e) {
ex.addSuppressed(e);
throw ex;
}
}
protected EL fetchFiltered() throws EX {
EX ex = null;
// get element in current class
try {
EL el = fetchFromClass(reflectClass.clazz);
setAccessible(el);
return el;
} catch (ReflectiveOperationException e) {
@SuppressWarnings("unchecked")
EX ee = (EX) e;
ex = ee;
}
// trying to bypass filtered member
try {
@SuppressWarnings("unchecked")
EL[] elements = (EL[]) Reflect.ofClassOfInstance(reflectClass.clazz)
.method(internalMethodNameElementArray(), boolean.class)
.invoke(reflectClass.clazz, false);
for (EL element : elements) {
if (isEqualOurElement(element)) {
// the values in the elements array have to be copied
// (using special private methods in reflection api) before using it
Object reflectionFactoryOfClazz = Reflect.ofClassOfInstance(reflectClass.clazz)
.method("getReflectionFactory")
.invoke(reflectClass.clazz);
@SuppressWarnings("unchecked")
EL copiedElement = (EL) Reflect.ofClassOfInstance(reflectionFactoryOfClazz)
.method(internalMethodNameCopyElement(), element.getClass())
.invoke(reflectionFactoryOfClazz, element);
EL el = copiedElement;
setAccessible(el);
return el;
}
}
} catch (ReflectiveOperationException e) {
ex.addSuppressed(e);
}
throw ex;
}
protected abstract EL fetchFromClass(Class<T> clazz) throws EX;
protected abstract EL fetchFromReflectClass(ReflectClass<?> rc) throws EX;
protected abstract boolean isEqualOurElement(EL el);
protected abstract String internalMethodNameElementArray();
protected abstract String internalMethodNameCopyElement();
protected abstract void setAccessible(EL el);
public EL get() {
return cached;
}
}
public static class ReflectField<T> extends ReflectClassEl<T> {
public static class ReflectField<T> extends ReflectMember<T, Field, NoSuchFieldException> {
String elementName;
private Field cached, cachedFiltered;
/* package */ ReflectField(ReflectClass<T> c, String name) {
super(c);
/* package */ ReflectField(ReflectClass<T> c, String name, boolean bypassFilter) throws NoSuchFieldException {
super(c, bypassFilter);
elementName = name;
}
public synchronized Field get() throws NoSuchFieldException {
if (cached == null) {
cached = getDeclaredRecursively(reflectClass.clazz,
c -> c.getDeclaredField(elementName),
c -> ofClass(c).field(elementName).get(),
f -> f.setAccessible(true));
}
return cached;
}
@Override protected Field fetchFromClass(Class<T> clazz) throws NoSuchFieldException { return clazz.getDeclaredField(elementName); };
@Override protected Field fetchFromReflectClass(ReflectClass<?> rc) throws NoSuchFieldException { return rc.field(elementName).get(); };
@Override protected boolean isEqualOurElement(Field el) { return elementName.equals(el.getName()); };
@Override protected String internalMethodNameElementArray() { return "getDeclaredFields0"; };
@Override protected String internalMethodNameCopyElement() { return "copyField"; };
@Override protected void setAccessible(Field el) { el.setAccessible(true); }
/* package */ synchronized Field getFiltered() throws NoSuchFieldException {
if (cachedFiltered == null) {
cachedFiltered = Reflect.getFiltered(reflectClass.clazz,
c -> c.getDeclaredField(elementName),
f -> f.setAccessible(true),
f -> elementName.equals(f.getName()),
"getDeclaredFields0", "copyField");
}
return cachedFiltered;
}
public Object getValue(Object instance) throws ReflectiveOperationException {
return get().get(instance);
@ -225,7 +343,7 @@ public class Reflect {
// change the modifier in the Field instance so the method #set(instance, value) doesnt throw an exception
int modifiers = f.getModifiers();
if (Modifier.isFinal(modifiers)) {
ofClass(Field.class).field("modifiers").getFiltered().set(f, modifiers & ~Modifier.FINAL);
ofClass(Field.class).field("modifiers").fetchFiltered().set(f, modifiers & ~Modifier.FINAL);
}
f.set(instance, value);
}
@ -243,42 +361,31 @@ public class Reflect {
}
public static class ReflectMethod<T> extends ReflectClassEl<T> {
String elementName;
private Method cached, cachedFiltered;
public static class ReflectMethod<T> extends ReflectMember<T, Method, NoSuchMethodException> {
String elementName;
MethodIdentifier methodId;
Class<?>[] parameterTypes;
/* package */ ReflectMethod(ReflectClass<T> c, MethodIdentifier methodId) {
super(c);
/* package */ ReflectMethod(ReflectClass<T> c, MethodIdentifier methodId, boolean bypassFilter) throws NoSuchMethodException {
super(c, bypassFilter);
this.elementName = methodId.methodName;
this.methodId = methodId;
parameterTypes = methodId.parameters;
}
public Method get() throws NoSuchMethodException {
if (cached == null) {
cached = getDeclaredRecursively(reflectClass.clazz,
c -> c.getDeclaredMethod(elementName, parameterTypes),
c -> ofClass(c).method(methodId).get(),
m -> m.setAccessible(true));
}
return cached;
}
/* package */ Method getFiltered() throws NoSuchMethodException {
if (cachedFiltered == null) {
cachedFiltered = Reflect.getFiltered(reflectClass.clazz,
c -> c.getDeclaredMethod(elementName, parameterTypes),
m -> m.setAccessible(true),
m -> elementName.equals(m.getName()) && Arrays.equals(parameterTypes, m.getParameterTypes()),
"getDeclaredMethods0", "copyMethod");
}
return cachedFiltered;
}
@Override protected Method fetchFromClass(Class<T> clazz) throws NoSuchMethodException { return clazz.getDeclaredMethod(elementName, parameterTypes); };
@Override protected Method fetchFromReflectClass(ReflectClass<?> rc) throws NoSuchMethodException { return rc.method(methodId, false).get(); };
@Override protected boolean isEqualOurElement(Method el) { return elementName.equals(el.getName()) && Arrays.equals(parameterTypes, el.getParameterTypes()); };
@Override protected String internalMethodNameElementArray() { return "getDeclaredMethods0"; };
@Override protected String internalMethodNameCopyElement() { return "copyMethod"; };
@Override protected void setAccessible(Method el) { el.setAccessible(true); }
public Object invoke(Object instance, Object... values) throws ReflectiveOperationException {
return get().invoke(instance, values);
@ -289,40 +396,37 @@ public class Reflect {
}
}
public static class ReflectConstructor<T> extends ReflectClassEl<T> {
private Constructor<T> cached, cachedFiltered;
public static class ReflectConstructor<T> extends ReflectMember<T, Constructor<T>, NoSuchMethodException> {
ConstructorIdentifier constructorId;
Class<?>[] parameterTypes;
/* package */ ReflectConstructor(ReflectClass<T> c, ConstructorIdentifier constructorId) {
super(c);
/* package */ ReflectConstructor(ReflectClass<T> c, ConstructorIdentifier constructorId, boolean bypassFilter) throws NoSuchMethodException {
super(c, bypassFilter);
this.constructorId = constructorId;
parameterTypes = constructorId.parameters;
}
public Constructor<T> get() throws NoSuchMethodException {
if (cached == null) {
Constructor<T> el = null;
el = reflectClass.clazz.getDeclaredConstructor(parameterTypes);
el.setAccessible(true);
cached = el;
}
return cached;
// Override since we don't want to recursively search for a constructor
@Override
protected Constructor<T> fetch() throws NoSuchMethodException {
Constructor<T> el = null;
el = fetchFromClass(reflectClass.clazz);
setAccessible(el);
return el;
}
/* package */ Constructor<T> getFiltered() throws NoSuchMethodException {
if (cachedFiltered == null) {
cachedFiltered = Reflect.getFiltered(reflectClass.clazz,
c -> c.getDeclaredConstructor(parameterTypes),
m -> m.setAccessible(true),
m -> Arrays.equals(parameterTypes, m.getParameterTypes()),
"getDeclaredConstructors0", "copyConstructor");
}
return cachedFiltered;
}
@Override protected Constructor<T> fetchFromClass(Class<T> clazz) throws NoSuchMethodException { return clazz.getDeclaredConstructor(parameterTypes); };
@Override protected Constructor<T> fetchFromReflectClass(ReflectClass<?> rc) throws NoSuchMethodException { throw new UnsupportedOperationException(); };
@Override protected boolean isEqualOurElement(Constructor<T> el) { return Arrays.equals(parameterTypes, el.getParameterTypes()); };
@Override protected String internalMethodNameElementArray() { return "getDeclaredConstructors0"; };
@Override protected String internalMethodNameCopyElement() { return "copyConstructor"; };
@Override protected void setAccessible(Constructor<T> el) { el.setAccessible(true); }
public T instanciate(Object... values) throws ReflectiveOperationException {
return get().newInstance(values);
@ -340,124 +444,10 @@ public class Reflect {
private interface GetUncheckedClassReflectiveElement<T, E extends ReflectiveOperationException> {
public T get(Class<?> clazz) throws E;
}
private interface GetReflectiveElement<C, T, E extends ReflectiveOperationException> {
public T get(Class<C> clazz) throws E;
}
private static <C, T, E extends ReflectiveOperationException> T getDeclaredRecursively(
Class<C> clazz, GetReflectiveElement<C, T, E> jlrGetter,
GetUncheckedClassReflectiveElement<T, E> parentGetter, Consumer<T> setAccessible) throws E {
Objects.requireNonNull(clazz, "Class instance not provided");
E ex = null;
T el = null;
// get element in provided class
try {
el = jlrGetter.get(clazz);
setAccessible.accept(el);
} catch (ReflectiveOperationException e) {
@SuppressWarnings("unchecked")
E ee = (E) e;
ex = ee;
}
// get element in parent class (will do recursion)
if (el == null) {
try {
el = parentGetter.get(clazz.getSuperclass());
} catch (ReflectiveOperationException e) {
if (ex == null) {
@SuppressWarnings("unchecked")
E ee = (E) e;
ex = ee;
}
else {
ex.addSuppressed(e);
}
}
}
if (el == null)
throw ex;
return el;
}
/**
* Get a Field or Method of a class that is not accessible using {@link Class#getDeclaredField(String)}
* or using {@link Class#getDeclaredMethod(String, Class...)} because the implementation of {@link Class}
* block its direct access.
*
* This method calls an internal method of {@link Class} to retrieve the full list of field or method, then
* search in the list for the requested element.
*/
private static <C, T, E extends ReflectiveOperationException> T getFiltered(
Class<C> clazz, GetReflectiveElement<C, T, E> jlrGetter,
Consumer<T> setAccessible, Predicate<T> elementChecker,
String privateMethodName, String copyMethodName) throws E {
Objects.requireNonNull(clazz, "Class instance not provided");
T el = null;
E ex = null;
try {
el = jlrGetter.get(clazz);
} catch (ReflectiveOperationException e) {
@SuppressWarnings("unchecked")
E ee = (E) e;
ex = ee;
}
try {
@SuppressWarnings("unchecked")
T[] elements = (T[]) ofClassOfInstance(clazz).method(privateMethodName, boolean.class).invoke(clazz, false);
for (T element : elements) {
if (elementChecker.test(element)) {
// the values in the elements array have to be copied
// (using special private methods in reflection api) before using it
Object reflectionFactoryOfClazz = ofClassOfInstance(clazz).method("getReflectionFactory").invoke(clazz);
@SuppressWarnings("unchecked")
T copiedElement = (T) ofClassOfInstance(reflectionFactoryOfClazz)
.method(copyMethodName, element.getClass())
.invoke(reflectionFactoryOfClazz, element);
el = copiedElement;
break;
}
}
} catch (ReflectiveOperationException e) {
if (ex != null)
ex.addSuppressed(e);
}
if (el == null)
throw ex;
setAccessible.accept(el);
return el;
}
private static Cache<Class<?>, List<Class<?>>> subClassesLists = CacheBuilder.newBuilder()
private static Cache<Class<?>, List<Class<?>>> subClassesLists = CacheBuilder.newBuilder()
.expireAfterAccess(10, TimeUnit.MINUTES)
.build();