/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* Copyright (C) 2006-2007 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package java.lang;
import dalvik.system.VMStack;
import java.io.InputStream;
import java.io.Serializable;
import java.lang.annotation.Annotation;
import java.lang.annotation.Inherited;
import java.lang.reflect.AnnotatedElement;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.GenericDeclaration;
import java.lang.reflect.Member;
import java.lang.reflect.Method;
import java.lang.reflect.Modifier;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.net.URL;
import java.security.ProtectionDomain;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashMap;
import java.util.List;
import libcore.util.CollectionUtils;
import libcore.util.EmptyArray;
import org.apache.harmony.kernel.vm.StringUtils;
import org.apache.harmony.luni.lang.reflect.GenericSignatureParser;
import org.apache.harmony.luni.lang.reflect.Types;
/**
* The in-memory representation of a Java class. This representation serves as
* the starting point for querying class-related information, a process usually
* called "reflection". There are basically three types of {@code Class}
* instances: those representing real classes and interfaces, those representing
* primitive types, and those representing array classes.
*
* <h4>Class instances representing object types (classes or interfaces)</h4>
* <p>
* These represent an ordinary class or interface as found in the class
* hierarchy. The name associated with these {@code Class} instances is simply
* the fully qualified class name of the class or interface that it represents.
* In addition to this human-readable name, each class is also associated by a
* so-called <em>signature</em>, which is the letter "L", followed by the
* class name and a semicolon (";"). The signature is what the runtime system
* uses internally for identifying the class (for example in a DEX file).
* </p>
* <h4>Classes representing primitive types</h4>
* <p>
* These represent the standard Java primitive types and hence share their
* names (for example "int" for the {@code int} primitive type). Although it is
* not possible to create new instances based on these {@code Class} instances,
* they are still useful for providing reflection information, and as the
* component type of array classes. There is one {@code Class} instance for each
* primitive type, and their signatures are:
* </p>
* <ul>
* <li>{@code B} representing the {@code byte} primitive type</li>
* <li>{@code S} representing the {@code short} primitive type</li>
* <li>{@code I} representing the {@code int} primitive type</li>
* <li>{@code J} representing the {@code long} primitive type</li>
* <li>{@code F} representing the {@code float} primitive type</li>
* <li>{@code D} representing the {@code double} primitive type</li>
* <li>{@code C} representing the {@code char} primitive type</li>
* <li>{@code Z} representing the {@code boolean} primitive type</li>
* <li>{@code V} representing void function return values</li>
* </ul>
* <p>
* <h4>Classes representing array classes</h4>
* <p>
* These represent the classes of Java arrays. There is one such {@code Class}
* instance per combination of array leaf component type and arity (number of
* dimensions). In this case, the name associated with the {@code Class}
* consists of one or more left square brackets (one per dimension in the array)
* followed by the signature of the class representing the leaf component type,
* which can be either an object type or a primitive type. The signature of a
* {@code Class} representing an array type is the same as its name. Examples
* of array class signatures are:
* </p>
* <ul>
* <li>{@code [I} representing the {@code int[]} type</li>
* <li>{@code [Ljava/lang/String;} representing the {@code String[]} type</li>
* <li>{@code [[[C} representing the {@code char[][][]} type (three dimensions!)</li>
* </ul>
*/
public final class Class<T> implements Serializable, AnnotatedElement, GenericDeclaration, Type {
private static final long serialVersionUID = 3206093459760846163L;
/**
* Lazily computed name of this class; always prefer calling getName().
*/
private transient String name;
private Class() {
// Prevent this class to be instantiated, instance
// should be created by JVM only
}
/**
* Get the Signature attribute for this class. Returns null if not found.
*/
private String getSignatureAttribute() {
Object[] annotation = getSignatureAnnotation();
if (annotation == null) {
return null;
}
return StringUtils.combineStrings(annotation);
}
/**
* Get the Signature annotation for this class. Returns null if not found.
*/
native private Object[] getSignatureAnnotation();
/**
* Returns a {@code Class} object which represents the class with the
* specified name. The name should be the name of a class as described in
* the {@link Class class definition}; however, {@code Class}es representing
* primitive types can not be found using this method.
* <p>
* If the class has not been loaded so far, it is being loaded and linked
* first. This is done through either the class loader of the calling class
* or one of its parent class loaders. The class is also being initialized,
* which means that a possible static initializer block is executed.
*
* @param className
* the name of the non-primitive-type class to find.
* @return the named {@code Class} instance.
* @throws ClassNotFoundException
* if the requested class can not be found.
* @throws LinkageError
* if an error occurs during linkage
* @throws ExceptionInInitializerError
* if an exception occurs during static initialization of a
* class.
*/
public static Class<?> forName(String className) throws ClassNotFoundException {
return forName(className, true, VMStack.getCallingClassLoader());
}
/**
* Returns a {@code Class} object which represents the class with the
* specified name. The name should be the name of a class as described in
* the {@link Class class definition}, however {@code Class}es representing
* primitive types can not be found using this method. Security rules will
* be obeyed.
* <p>
* If the class has not been loaded so far, it is being loaded and linked
* first. This is done through either the specified class loader or one of
* its parent class loaders. The caller can also request the class to be
* initialized, which means that a possible static initializer block is
* executed.
*
* @param className
* the name of the non-primitive-type class to find.
* @param initializeBoolean
* indicates whether the class should be initialized.
* @param classLoader
* the class loader to use to load the class.
* @return the named {@code Class} instance.
* @throws ClassNotFoundException
* if the requested class can not be found.
* @throws LinkageError
* if an error occurs during linkage
* @throws ExceptionInInitializerError
* if an exception occurs during static initialization of a
* class.
*/
public static Class<?> forName(String className, boolean initializeBoolean,
ClassLoader classLoader) throws ClassNotFoundException {
if (classLoader == null) {
classLoader = ClassLoader.getSystemClassLoader();
}
// Catch an Exception thrown by the underlying native code. It wraps
// up everything inside a ClassNotFoundException, even if e.g. an
// Error occurred during initialization. This as a workaround for
// an ExceptionInInitilaizerError that's also wrapped. It is actually
// expected to be thrown. Maybe the same goes for other errors.
// Not wrapping up all the errors will break android though.
Class<?> result;
try {
result = classForName(className, initializeBoolean,
classLoader);
} catch (ClassNotFoundException e) {
Throwable cause = e.getCause();
if (cause instanceof ExceptionInInitializerError) {
throw (ExceptionInInitializerError) cause;
}
throw e;
}
return result;
}
/*
* Returns a class by name without any security checks.
*
* @param className The name of the non-primitive type class to find
* @param initializeBoolean A boolean indicating whether the class should be
* initialized
* @param classLoader The class loader to use to load the class
* @return the named class.
* @throws ClassNotFoundException If the class could not be found
*/
static native Class<?> classForName(String className, boolean initializeBoolean,
ClassLoader classLoader) throws ClassNotFoundException;
/**
* Returns an array containing {@code Class} objects for all public classes
* and interfaces that are members of this class. This includes public
* members inherited from super classes and interfaces. If there are no such
* class members or if this object represents a primitive type then an array
* of length 0 is returned.
*
* @return the public class members of the class represented by this object.
*/
public Class<?>[] getClasses() {
return getFullListOfClasses(true);
}
@Override public <A extends Annotation> A getAnnotation(Class<A> annotationType) {
if (annotationType == null) {
throw new NullPointerException("annotationType == null");
}
A annotation = getDeclaredAnnotation(annotationType);
if (annotation != null) {
return annotation;
}
if (annotationType.isAnnotationPresent(Inherited.class)) {
for (Class<?> sup = getSuperclass(); sup != null; sup = sup.getSuperclass()) {
annotation = sup.getDeclaredAnnotation(annotationType);
if (annotation != null) {
return annotation;
}
}
}
return null;
}
/**
* Returns all the annotations of this class. If there are no annotations
* then an empty array is returned.
*
* @return a copy of the array containing this class' annotations.
* @see #getDeclaredAnnotations()
*/
public Annotation[] getAnnotations() {
/*
* We need to get the annotations declared on this class, plus the
* annotations from superclasses that have the "@Inherited" annotation
* set. We create a temporary map to use while we accumulate the
* annotations and convert it to an array at the end.
*
* It's possible to have duplicates when annotations are inherited.
* We use a Map to filter those out.
*
* HashMap might be overkill here.
*/
HashMap<Class, Annotation> map = new HashMap<Class, Annotation>();
Annotation[] declaredAnnotations = getDeclaredAnnotations();
for (int i = declaredAnnotations.length-1; i >= 0; --i) {
map.put(declaredAnnotations[i].annotationType(), declaredAnnotations[i]);
}
for (Class<?> sup = getSuperclass(); sup != null; sup = sup.getSuperclass()) {
declaredAnnotations = sup.getDeclaredAnnotations();
for (int i = declaredAnnotations.length-1; i >= 0; --i) {
Class<?> clazz = declaredAnnotations[i].annotationType();
if (!map.containsKey(clazz) && clazz.isAnnotationPresent(Inherited.class)) {
map.put(clazz, declaredAnnotations[i]);
}
}
}
/* convert annotation values from HashMap to array */
Collection<Annotation> coll = map.values();
return coll.toArray(new Annotation[coll.size()]);
}
/**
* Returns the canonical name of this class. If this class does not have a
* canonical name as defined in the Java Language Specification, then the
* method returns {@code null}.
*
* @return this class' canonical name, or {@code null} if it does not have a
* canonical name.
*/
public String getCanonicalName() {
if (isLocalClass() || isAnonymousClass())
return null;
if (isArray()) {
/*
* The canonical name of an array type depends on the (existence of)
* the component type's canonical name.
*/
String name = getComponentType().getCanonicalName();
if (name != null) {
return name + "[]";
}
} else if (isMemberClass()) {
/*
* The canonical name of an inner class depends on the (existence
* of) the declaring class' canonical name.
*/
String name = getDeclaringClass().getCanonicalName();
if (name != null) {
return name + "." + getSimpleName();
}
} else {
/*
* The canonical name of a top-level class or primitive type is
* equal to the fully qualified name.
*/
return getName();
}
/*
* Other classes don't have a canonical name.
*/
return null;
}
/**
* Returns the class loader which was used to load the class represented by
* this {@code Class}. Implementations are free to return {@code null} for
* classes that were loaded by the bootstrap class loader. The Android
* reference implementation, though, returns a reference to an actual
* representation of the bootstrap class loader.
*
* @return the class loader for the represented class.
* @see ClassLoader
*/
public ClassLoader getClassLoader() {
if (this.isPrimitive()) {
return null;
}
ClassLoader loader = getClassLoaderImpl();
if (loader == null) {
loader = BootClassLoader.getInstance();
}
return loader;
}
/**
* This must be provided by the VM vendor, as it is used by other provided
* class implementations in this package. Outside of this class, it is used
* by SecurityManager.classLoaderDepth(),
* currentClassLoader() and currentLoadedClass(). Return the ClassLoader for
* this Class without doing any security checks. The bootstrap ClassLoader
* is returned, unlike getClassLoader() which returns null in place of the
* bootstrap ClassLoader.
*
* @return the ClassLoader
*/
ClassLoader getClassLoaderImpl() {
ClassLoader loader = getClassLoader(this);
return loader == null ? BootClassLoader.getInstance() : loader;
}
/*
* Returns the defining class loader for the given class.
*
* @param clazz the class the class loader of which we want
* @return the class loader
*/
private static native ClassLoader getClassLoader(Class<?> clazz);
/**
* Returns a {@code Class} object which represents the component type if
* this class represents an array type. Returns {@code null} if this class
* does not represent an array type. The component type of an array type is
* the type of the elements of the array.
*
* @return the component type of this class.
*/
public native Class<?> getComponentType();
/**
* Returns a {@code Constructor} object which represents the public
* constructor matching the specified parameter types.
*
* @param parameterTypes
* the parameter types of the requested constructor.
* {@code (Class[]) null} is equivalent to the empty array.
* @return the constructor described by {@code parameterTypes}.
* @throws NoSuchMethodException
* if the constructor can not be found.
* @see #getDeclaredConstructor(Class[])
*/
@SuppressWarnings("unchecked")
public Constructor<T> getConstructor(Class<?>... parameterTypes) throws NoSuchMethodException {
return (Constructor) getConstructorOrMethod("<init>", false, true, parameterTypes);
}
/**
* Returns a constructor or method with the specified name.
*
* @param name the method name, or "<init>" to return a constructor.
* @param recursive true to search supertypes.
*/
private Member getConstructorOrMethod(String name, boolean recursive,
boolean publicOnly, Class<?>[] parameterTypes) throws NoSuchMethodException {
if (recursive && !publicOnly) {
throw new AssertionError(); // can't lookup non-public members recursively
}
if (name == null) {
throw new NullPointerException("name == null");
}
if (parameterTypes == null) {
parameterTypes = EmptyArray.CLASS;
}
for (Class<?> c : parameterTypes) {
if (c == null) {
throw new NoSuchMethodException("parameter type is null");
}
}
Member result = recursive
? getPublicConstructorOrMethodRecursive(name, parameterTypes)
: Class.getDeclaredConstructorOrMethod(this, name, parameterTypes);
if (result == null || publicOnly && (result.getModifiers() & Modifier.PUBLIC) == 0) {
throw new NoSuchMethodException(name + " " + Arrays.toString(parameterTypes));
}
return result;
}
private Member getPublicConstructorOrMethodRecursive(String name, Class<?>[] parameterTypes) {
// search superclasses
for (Class<?> c = this; c != null; c = c.getSuperclass()) {
Member result = Class.getDeclaredConstructorOrMethod(c, name, parameterTypes);
if (result != null && (result.getModifiers() & Modifier.PUBLIC) != 0) {
return result;
}
}
// search implemented interfaces
for (Class<?> c = this; c != null; c = c.getSuperclass()) {
for (Class<?> ifc : c.getInterfaces()) {
Member result = ifc.getPublicConstructorOrMethodRecursive(name, parameterTypes);
if (result != null && (result.getModifiers() & Modifier.PUBLIC) != 0) {
return result;
}
}
}
return null;
}
/**
* Returns an array containing {@code Constructor} objects for all public
* constructors for the class represented by this {@code Class}. If there
* are no public constructors or if this {@code Class} represents an array
* class, a primitive type or void then an empty array is returned.
*
* @return an array with the public constructors of the class represented by
* this {@code Class}.
* @see #getDeclaredConstructors()
*/
public Constructor<?>[] getConstructors() {
return getDeclaredConstructors(this, true);
}
/**
* Returns the annotations that are directly defined on the class
* represented by this {@code Class}. Annotations that are inherited are not
* included in the result. If there are no annotations at all, an empty
* array is returned.
*
* @return a copy of the array containing the annotations defined for the
* class that this {@code Class} represents.
* @see #getAnnotations()
*/
native public Annotation[] getDeclaredAnnotations();
/**
* Returns the annotation if it exists.
*/
native private <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass);
/**
* Returns true if the annotation exists.
*/
native private boolean isDeclaredAnnotationPresent(Class<? extends Annotation> annotationClass);
/**
* Returns an array containing {@code Class} objects for all classes and
* interfaces that are declared as members of the class which this {@code
* Class} represents. If there are no classes or interfaces declared or if
* this class represents an array class, a primitive type or void, then an
* empty array is returned.
*
* @return an array with {@code Class} objects for all the classes and
* interfaces that are used in member declarations.
*/
public Class<?>[] getDeclaredClasses() {
return getDeclaredClasses(this, false);
}
/*
* Returns the list of member classes without performing any security checks
* first. This includes the member classes inherited from superclasses. If no
* member classes exist at all, an empty array is returned.
*
* @param publicOnly reflects whether we want only public members or all of them
* @return the list of classes
*/
private Class<?>[] getFullListOfClasses(boolean publicOnly) {
Class<?>[] result = getDeclaredClasses(this, publicOnly);
// Traverse all superclasses
Class<?> clazz = this.getSuperclass();
while (clazz != null) {
Class<?>[] temp = getDeclaredClasses(clazz, publicOnly);
if (temp.length != 0) {
result = arraycopy(new Class[result.length + temp.length], result, temp);
}
clazz = clazz.getSuperclass();
}
return result;
}
/*
* Returns the list of member classes of the given class. No security checks
* are performed. If no members exist, an empty array is returned.
*
* @param clazz the class the members of which we want
* @param publicOnly reflects whether we want only public member or all of them
* @return the class' class members
*/
private static native Class<?>[] getDeclaredClasses(Class<?> clazz, boolean publicOnly);
/**
* Returns a {@code Constructor} object which represents the constructor
* matching the specified parameter types that is declared by the class
* represented by this {@code Class}.
*
* @param parameterTypes
* the parameter types of the requested constructor.
* {@code (Class[]) null} is equivalent to the empty array.
* @return the constructor described by {@code parameterTypes}.
* @throws NoSuchMethodException
* if the requested constructor can not be found.
* @see #getConstructor(Class[])
*/
@SuppressWarnings("unchecked")
public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
throws NoSuchMethodException {
return (Constructor) getConstructorOrMethod("<init>", false, false, parameterTypes);
}
/**
* Returns an array containing {@code Constructor} objects for all
* constructors declared in the class represented by this {@code Class}. If
* there are no constructors or if this {@code Class} represents an array
* class, a primitive type or void then an empty array is returned.
*
* @return an array with the constructors declared in the class represented
* by this {@code Class}.
* @see #getConstructors()
*/
public Constructor<?>[] getDeclaredConstructors() {
return getDeclaredConstructors(this, false);
}
/*
* Returns the list of constructors without performing any security checks
* first. If no constructors exist, an empty array is returned.
*
* @param clazz the class of interest
* @param publicOnly reflects whether we want only public constructors or all of them
* @return the list of constructors
*/
private static native <T> Constructor<T>[] getDeclaredConstructors(
Class<T> clazz, boolean publicOnly);
/**
* Returns a {@code Field} object for the field with the specified name
* which is declared in the class represented by this {@code Class}.
*
* @param name the name of the requested field.
* @return the requested field in the class represented by this class.
* @throws NoSuchFieldException if the requested field can not be found.
* @see #getField(String)
*/
public Field getDeclaredField(String name) throws NoSuchFieldException {
if (name == null) {
throw new NullPointerException("name == null");
}
Field result = getDeclaredField(this, name);
if (result == null) {
throw new NoSuchFieldException(name);
}
return result;
}
/**
* Returns an array containing {@code Field} objects for all fields declared
* in the class represented by this {@code Class}. If there are no fields or
* if this {@code Class} represents an array class, a primitive type or void
* then an empty array is returned.
*
* @return an array with the fields declared in the class represented by
* this class.
* @see #getFields()
*/
public Field[] getDeclaredFields() {
return getDeclaredFields(this, false);
}
/*
* Returns the list of fields without performing any security checks
* first. If no fields exist at all, an empty array is returned.
*
* @param clazz the class of interest
* @param publicOnly reflects whether we want only public fields or all of them
* @return the list of fields
*/
static native Field[] getDeclaredFields(Class<?> clazz, boolean publicOnly);
/**
* Returns the field if it is defined by {@code clazz}; null otherwise. This
* may return a non-public member.
*/
static native Field getDeclaredField(Class<?> clazz, String name);
/**
* Returns a {@code Method} object which represents the method matching the
* specified name and parameter types that is declared by the class
* represented by this {@code Class}.
*
* @param name
* the requested method's name.
* @param parameterTypes
* the parameter types of the requested method.
* {@code (Class[]) null} is equivalent to the empty array.
* @return the method described by {@code name} and {@code parameterTypes}.
* @throws NoSuchMethodException
* if the requested constructor can not be found.
* @throws NullPointerException
* if {@code name} is {@code null}.
* @see #getMethod(String, Class[])
*/
public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
throws NoSuchMethodException {
Member member = getConstructorOrMethod(name, false, false, parameterTypes);
if (member instanceof Constructor) {
throw new NoSuchMethodException(name);
}
return (Method) member;
}
/**
* Returns an array containing {@code Method} objects for all methods
* declared in the class represented by this {@code Class}. If there are no
* methods or if this {@code Class} represents an array class, a primitive
* type or void then an empty array is returned.
*
* @return an array with the methods declared in the class represented by
* this {@code Class}.
* @see #getMethods()
*/
public Method[] getDeclaredMethods() {
return getDeclaredMethods(this, false);
}
/**
* Returns the list of methods without performing any security checks
* first. If no methods exist, an empty array is returned.
*/
static native Method[] getDeclaredMethods(Class<?> clazz, boolean publicOnly);
/**
* Returns the constructor or method if it is defined by {@code clazz}; null
* otherwise. This may return a non-public member.
*
* @param name the method name, or "<init>" to get a constructor.
*/
static native Member getDeclaredConstructorOrMethod(Class clazz, String name, Class[] args);
/**
* Returns the declaring {@code Class} of this {@code Class}. Returns
* {@code null} if the class is not a member of another class or if this
* {@code Class} represents an array class, a primitive type or void.
*
* @return the declaring {@code Class} or {@code null}.
*/
native public Class<?> getDeclaringClass();
/**
* Returns the enclosing {@code Class} of this {@code Class}. If there is no
* enclosing class the method returns {@code null}.
*
* @return the enclosing {@code Class} or {@code null}.
*/
native public Class<?> getEnclosingClass();
/**
* Gets the enclosing {@code Constructor} of this {@code Class}, if it is an
* anonymous or local/automatic class; otherwise {@code null}.
*
* @return the enclosing {@code Constructor} instance or {@code null}.
*/
native public Constructor<?> getEnclosingConstructor();
/**
* Gets the enclosing {@code Method} of this {@code Class}, if it is an
* anonymous or local/automatic class; otherwise {@code null}.
*
* @return the enclosing {@code Method} instance or {@code null}.
*/
native public Method getEnclosingMethod();
/**
* Gets the {@code enum} constants associated with this {@code Class}.
* Returns {@code null} if this {@code Class} does not represent an {@code
* enum} type.
*
* @return an array with the {@code enum} constants or {@code null}.
*/
@SuppressWarnings("unchecked") // we only cast after confirming that this class is an enum
public T[] getEnumConstants() {
if (!isEnum()) {
return null;
}
return (T[]) Enum.getSharedConstants((Class) this).clone();
}
/**
* Returns a {@code Field} object which represents the public field with the
* specified name. This method first searches the class C represented by
* this {@code Class}, then the interfaces implemented by C and finally the
* superclasses of C.
*
* @param name
* the name of the requested field.
* @return the public field specified by {@code name}.
* @throws NoSuchFieldException
* if the field can not be found.
* @see #getDeclaredField(String)
*/
public Field getField(String name) throws NoSuchFieldException {
if (name == null) {
throw new NullPointerException("name == null");
}
Field result = getPublicFieldRecursive(name);
if (result == null) {
throw new NoSuchFieldException(name);
}
return result;
}
private Field getPublicFieldRecursive(String name) {
// search superclasses
for (Class<?> c = this; c != null; c = c.getSuperclass()) {
Field result = Class.getDeclaredField(c, name);
if (result != null && (result.getModifiers() & Modifier.PUBLIC) != 0) {
return result;
}
}
// search implemented interfaces
for (Class<?> c = this; c != null; c = c.getSuperclass()) {
for (Class<?> ifc : c.getInterfaces()) {
Field result = ifc.getPublicFieldRecursive(name);
if (result != null && (result.getModifiers() & Modifier.PUBLIC) != 0) {
return result;
}
}
}
return null;
}
/**
* Returns an array containing {@code Field} objects for all public fields
* for the class C represented by this {@code Class}. Fields may be declared
* in C, the interfaces it implements or in the superclasses of C. The
* elements in the returned array are in no particular order.
*
* <p>If there are no public fields or if this class represents an array class,
* a primitive type or {@code void} then an empty array is returned.
*
* @return an array with the public fields of the class represented by this
* {@code Class}.
* @see #getDeclaredFields()
*/
public Field[] getFields() {
List<Field> fields = new ArrayList<Field>();
getPublicFieldsRecursive(fields);
/*
* The result may include duplicates when clazz implements an interface
* through multiple paths. Remove those duplicates.
*/
CollectionUtils.removeDuplicates(fields, Field.ORDER_BY_NAME_AND_DECLARING_CLASS);
return fields.toArray(new Field[fields.size()]);
}
/**
* Populates {@code result} with public fields defined by this class, its
* superclasses, and all implemented interfaces.
*/
private void getPublicFieldsRecursive(List<Field> result) {
// search superclasses
for (Class<?> c = this; c != null; c = c.getSuperclass()) {
for (Field field : Class.getDeclaredFields(c, true)) {
result.add(field);
}
}
// search implemented interfaces
for (Class<?> c = this; c != null; c = c.getSuperclass()) {
for (Class<?> ifc : c.getInterfaces()) {
ifc.getPublicFieldsRecursive(result);
}
}
}
/**
* Gets the {@link Type}s of the interfaces that this {@code Class} directly
* implements. If the {@code Class} represents a primitive type or {@code
* void} then an empty array is returned.
*
* @return an array of {@link Type} instances directly implemented by the
* class represented by this {@code class}.
*/
public Type[] getGenericInterfaces() {
GenericSignatureParser parser = new GenericSignatureParser(getClassLoader());
parser.parseForClass(this, getSignatureAttribute());
return Types.getClonedTypeArray(parser.interfaceTypes);
}
/**
* Gets the {@code Type} that represents the superclass of this {@code
* class}.
*
* @return an instance of {@code Type} representing the superclass.
*/
public Type getGenericSuperclass() {
GenericSignatureParser parser = new GenericSignatureParser(getClassLoader());
parser.parseForClass(this, getSignatureAttribute());
return Types.getType(parser.superclassType);
}
/**
* Returns an array of {@code Class} objects that match the interfaces
* specified in the {@code implements} declaration of the class represented
* by this {@code Class}. The order of the elements in the array is
* identical to the order in the original class declaration. If the class
* does not implement any interfaces, an empty array is returned.
*
* @return an array with the interfaces of the class represented by this
* class.
*/
public native Class<?>[] getInterfaces();
/**
* Returns a {@code Method} object which represents the public method with
* the specified name and parameter types. This method first searches the
* class C represented by this {@code Class}, then the superclasses of C and
* finally the interfaces implemented by C and finally the superclasses of C
* for a method with matching name.
*
* @param name
* the requested method's name.
* @param parameterTypes
* the parameter types of the requested method.
* {@code (Class[]) null} is equivalent to the empty array.
* @return the public field specified by {@code name}.
* @throws NoSuchMethodException
* if the method can not be found.
* @see #getDeclaredMethod(String, Class[])
*/
public Method getMethod(String name, Class<?>... parameterTypes) throws NoSuchMethodException {
Member member = getConstructorOrMethod(name, true, true, parameterTypes);
if (member instanceof Constructor) {
throw new NoSuchMethodException(name);
}
return (Method) member;
}
/**
* Returns an array containing {@code Method} objects for all public methods
* for the class C represented by this {@code Class}. Methods may be
* declared in C, the interfaces it implements or in the superclasses of C.
* The elements in the returned array are in no particular order.
* <p>
* If there are no public methods or if this {@code Class} represents a
* primitive type or {@code void} then an empty array is returned.
* </p>
*
* @return an array with the methods of the class represented by this
* {@code Class}.
* @see #getDeclaredMethods()
*/
public Method[] getMethods() {
List<Method> methods = new ArrayList<Method>();
getPublicMethodsRecursive(methods);
/*
* Remove methods defined by multiple types, preferring to keep methods
* declared by derived types.
*/
CollectionUtils.removeDuplicates(methods, Method.ORDER_BY_SIGNATURE);
return methods.toArray(new Method[methods.size()]);
}
/**
* Populates {@code result} with public methods defined by {@code clazz}, its
* superclasses, and all implemented interfaces, including overridden methods.
*/
private void getPublicMethodsRecursive(List<Method> result) {
// search superclasses
for (Class<?> c = this; c != null; c = c.getSuperclass()) {
for (Method method : Class.getDeclaredMethods(c, true)) {
result.add(method);
}
}
// search implemented interfaces
for (Class<?> c = this; c != null; c = c.getSuperclass()) {
for (Class<?> ifc : c.getInterfaces()) {
ifc.getPublicMethodsRecursive(result);
}
}
}
/**
* Returns an integer that represents the modifiers of the class represented
* by this {@code Class}. The returned value is a combination of bits
* defined by constants in the {@link Modifier} class.
*
* @return the modifiers of the class represented by this {@code Class}.
*/
public int getModifiers() {
return getModifiers(this, false);
}
/*
* Return the modifiers for the given class.
*
* @param clazz the class of interest
* @ignoreInnerClassesAttrib determines whether we look for and use the
* flags from an "inner class" attribute
*/
private static native int getModifiers(Class<?> clazz, boolean ignoreInnerClassesAttrib);
/**
* Returns the name of the class represented by this {@code Class}. For a
* description of the format which is used, see the class definition of
* {@link Class}.
*
* @return the name of the class represented by this {@code Class}.
*/
public String getName() {
String result = name;
return (result == null) ? (name = getNameNative()) : result;
}
private native String getNameNative();
/**
* Returns the simple name of the class represented by this {@code Class} as
* defined in the source code. If there is no name (that is, the class is
* anonymous) then an empty string is returned. If the receiver is an array
* then the name of the underlying type with square braces appended (for
* example {@code "Integer[]"}) is returned.
*
* @return the simple name of the class represented by this {@code Class}.
*/
public String getSimpleName() {
if (isArray()) {
return getComponentType().getSimpleName() + "[]";
}
String name = getName();
if (isAnonymousClass()) {
return "";
}
if (isMemberClass() || isLocalClass()) {
return getInnerClassName();
}
int dot = name.lastIndexOf('.');
if (dot != -1) {
return name.substring(dot + 1);
}
return name;
}
/*
* Returns the simple name of a member or local class, or null otherwise.
*
* @return The name.
*/
private native String getInnerClassName();
/**
* Returns null.
*/
public ProtectionDomain getProtectionDomain() {
return null;
}
/**
* Returns the URL of the resource specified by {@code resName}. The mapping
* between the resource name and the URL is managed by the class' class
* loader.
*
* @param resName
* the name of the resource.
* @return the requested resource's {@code URL} object or {@code null} if
* the resource can not be found.
* @see ClassLoader
*/
public URL getResource(String resName) {
// Get absolute resource name, but without the leading slash
if (resName.startsWith("/")) {
resName = resName.substring(1);
} else {
String pkg = getName();
int dot = pkg.lastIndexOf('.');
if (dot != -1) {
pkg = pkg.substring(0, dot).replace('.', '/');
} else {
pkg = "";
}
resName = pkg + "/" + resName;
}
// Delegate to proper class loader
ClassLoader loader = getClassLoader();
if (loader != null) {
return loader.getResource(resName);
} else {
return ClassLoader.getSystemResource(resName);
}
}
/**
* Returns a read-only stream for the contents of the resource specified by
* {@code resName}. The mapping between the resource name and the stream is
* managed by the class' class loader.
*
* @param resName
* the name of the resource.
* @return a stream for the requested resource or {@code null} if no
* resource with the specified name can be found.
* @see ClassLoader
*/
public InputStream getResourceAsStream(String resName) {
// Get absolute resource name, but without the leading slash
if (resName.startsWith("/")) {
resName = resName.substring(1);
} else {
String pkg = getName();
int dot = pkg.lastIndexOf('.');
if (dot != -1) {
pkg = pkg.substring(0, dot).replace('.', '/');
} else {
pkg = "";
}
resName = pkg + "/" + resName;
}
// Delegate to proper class loader
ClassLoader loader = getClassLoader();
if (loader != null) {
return loader.getResourceAsStream(resName);
} else {
return ClassLoader.getSystemResourceAsStream(resName);
}
}
/**
* Returns null. (On Android, a {@code ClassLoader} can load classes from multiple dex files.
* All classes from any given dex file will have the same signers, but different dex
* files may have different signers. This does not fit well with the original
* {@code ClassLoader}-based model of {@code getSigners}.)
*
* @return null.
*/
public Object[] getSigners() {
// See http://code.google.com/p/android/issues/detail?id=1766.
return null;
}
/**
* Returns the {@code Class} object which represents the superclass of the
* class represented by this {@code Class}. If this {@code Class} represents
* the {@code Object} class, a primitive type, an interface or void then the
* method returns {@code null}. If this {@code Class} represents an array
* class then the {@code Object} class is returned.
*
* @return the superclass of the class represented by this {@code Class}.
*/
public native Class<? super T> getSuperclass();
/**
* Returns an array containing {@code TypeVariable} objects for type
* variables declared by the generic class represented by this {@code
* Class}. Returns an empty array if the class is not generic.
*
* @return an array with the type variables of the class represented by this
* class.
*/
@SuppressWarnings("unchecked")
public synchronized TypeVariable<Class<T>>[] getTypeParameters() {
GenericSignatureParser parser = new GenericSignatureParser(getClassLoader());
parser.parseForClass(this, getSignatureAttribute());
return parser.formalTypeParameters.clone();
}
/**
* Indicates whether this {@code Class} represents an annotation class.
*
* @return {@code true} if this {@code Class} represents an annotation
* class; {@code false} otherwise.
*/
public boolean isAnnotation() {
final int ACC_ANNOTATION = 0x2000; // not public in reflect.Modifiers
int mod = getModifiers(this, true);
return (mod & ACC_ANNOTATION) != 0;
}
@Override public boolean isAnnotationPresent(Class<? extends Annotation> annotationType) {
if (annotationType == null) {
throw new NullPointerException("annotationType == null");
}
if (isDeclaredAnnotationPresent(annotationType)) {
return true;
}
if (annotationType.isDeclaredAnnotationPresent(Inherited.class)) {
for (Class<?> sup = getSuperclass(); sup != null; sup = sup.getSuperclass()) {
if (sup.isDeclaredAnnotationPresent(annotationType)) {
return true;
}
}
}
return false;
}
/**
* Indicates whether the class represented by this {@code Class} is
* anonymously declared.
*
* @return {@code true} if the class represented by this {@code Class} is
* anonymous; {@code false} otherwise.
*/
native public boolean isAnonymousClass();
/**
* Indicates whether the class represented by this {@code Class} is an array
* class.
*
* @return {@code true} if the class represented by this {@code Class} is an
* array class; {@code false} otherwise.
*/
public boolean isArray() {
return getComponentType() != null;
}
/**
* Indicates whether the specified class type can be converted to the class
* represented by this {@code Class}. Conversion may be done via an identity
* conversion or a widening reference conversion (if either the receiver or
* the argument represent primitive types, only the identity conversion
* applies).
*
* @param cls
* the class to check.
* @return {@code true} if {@code cls} can be converted to the class
* represented by this {@code Class}; {@code false} otherwise.
* @throws NullPointerException
* if {@code cls} is {@code null}.
*/
public native boolean isAssignableFrom(Class<?> cls);
/**
* Indicates whether the class represented by this {@code Class} is an
* {@code enum}.
*
* @return {@code true} if the class represented by this {@code Class} is an
* {@code enum}; {@code false} otherwise.
*/
public boolean isEnum() {
return ((getModifiers() & 0x4000) != 0) && (getSuperclass() == Enum.class);
}
/**
* Indicates whether the specified object can be cast to the class
* represented by this {@code Class}. This is the runtime version of the
* {@code instanceof} operator.
*
* @param object
* the object to check.
* @return {@code true} if {@code object} can be cast to the type
* represented by this {@code Class}; {@code false} if {@code
* object} is {@code null} or cannot be cast.
*/
public native boolean isInstance(Object object);
/**
* Indicates whether this {@code Class} represents an interface.
*
* @return {@code true} if this {@code Class} represents an interface;
* {@code false} otherwise.
*/
public native boolean isInterface();
/**
* Indicates whether the class represented by this {@code Class} is defined
* locally.
*
* @return {@code true} if the class represented by this {@code Class} is
* defined locally; {@code false} otherwise.
*/
public boolean isLocalClass() {
boolean enclosed = (getEnclosingMethod() != null ||
getEnclosingConstructor() != null);
return enclosed && !isAnonymousClass();
}
/**
* Indicates whether the class represented by this {@code Class} is a member
* class.
*
* @return {@code true} if the class represented by this {@code Class} is a
* member class; {@code false} otherwise.
*/
public boolean isMemberClass() {
return getDeclaringClass() != null;
}
/**
* Indicates whether this {@code Class} represents a primitive type.
*
* @return {@code true} if this {@code Class} represents a primitive type;
* {@code false} otherwise.
*/
public native boolean isPrimitive();
/**
* Indicates whether this {@code Class} represents a synthetic type.
*
* @return {@code true} if this {@code Class} represents a synthetic type;
* {@code false} otherwise.
*/
public boolean isSynthetic() {
final int ACC_SYNTHETIC = 0x1000; // not public in reflect.Modifiers
int mod = getModifiers(this, true);
return (mod & ACC_SYNTHETIC) != 0;
}
/**
* Returns a new instance of the class represented by this {@code Class},
* created by invoking the default (that is, zero-argument) constructor. If
* there is no such constructor, or if the creation fails (either because of
* a lack of available memory or because an exception is thrown by the
* constructor), an {@code InstantiationException} is thrown. If the default
* constructor exists but is not accessible from the context where this
* method is invoked, an {@code IllegalAccessException} is thrown.
*
* @return a new instance of the class represented by this {@code Class}.
* @throws IllegalAccessException
* if the default constructor is not visible.
* @throws InstantiationException
* if the instance can not be created.
*/
public T newInstance() throws InstantiationException, IllegalAccessException {
return newInstanceImpl();
}
private native T newInstanceImpl() throws IllegalAccessException, InstantiationException;
@Override
public String toString() {
if (isPrimitive()) {
return getSimpleName();
} else {
return (isInterface() ? "interface " : "class ") + getName();
}
}
/**
* Returns the {@code Package} of which the class represented by this
* {@code Class} is a member. Returns {@code null} if no {@code Package}
* object was created by the class loader of the class.
*
* @return Package the {@code Package} of which this {@code Class} is a
* member or {@code null}.
*/
public Package getPackage() {
// TODO This might be a hack, but the VM doesn't have the necessary info.
ClassLoader loader = getClassLoader();
if (loader != null) {
String name = getName();
int dot = name.lastIndexOf('.');
return (dot != -1 ? loader.getPackage(name.substring(0, dot)) : null);
}
return null;
}
/**
* Returns the assertion status for the class represented by this {@code
* Class}. Assertion is enabled / disabled based on the class loader,
* package or class default at runtime.
*
* @return the assertion status for the class represented by this {@code
* Class}.
*/
public native boolean desiredAssertionStatus();
/**
* Casts this {@code Class} to represent a subclass of the specified class.
* If successful, this {@code Class} is returned; otherwise a {@code
* ClassCastException} is thrown.
*
* @param clazz
* the required type.
* @return this {@code Class} cast as a subclass of the given type.
* @throws ClassCastException
* if this {@code Class} cannot be cast to the specified type.
*/
@SuppressWarnings("unchecked")
public <U> Class<? extends U> asSubclass(Class<U> clazz) {
if (clazz.isAssignableFrom(this)) {
return (Class<? extends U>)this;
}
String actualClassName = this.getName();
String desiredClassName = clazz.getName();
throw new ClassCastException(actualClassName + " cannot be cast to " + desiredClassName);
}
/**
* Casts the specified object to the type represented by this {@code Class}.
* If the object is {@code null} then the result is also {@code null}.
*
* @param obj
* the object to cast.
* @return the object that has been cast.
* @throws ClassCastException
* if the object cannot be cast to the specified type.
*/
@SuppressWarnings("unchecked")
public T cast(Object obj) {
if (obj == null) {
return null;
} else if (this.isInstance(obj)) {
return (T)obj;
}
String actualClassName = obj.getClass().getName();
String desiredClassName = this.getName();
throw new ClassCastException(actualClassName + " cannot be cast to " + desiredClassName);
}
/**
* Copies two arrays into one. Assumes that the destination array is large
* enough.
*
* @param result the destination array
* @param head the first source array
* @param tail the second source array
* @return the destination array, that is, result
*/
private static <T extends Object> T[] arraycopy(T[] result, T[] head, T[] tail) {
System.arraycopy(head, 0, result, 0, head.length);
System.arraycopy(tail, 0, result, head.length, tail.length);
return result;
}
}