/*
* JBoss, Home of Professional Open Source
* Copyright 2010, Red Hat, Inc. and/or its affiliates, and individual contributors
* by the @authors tag. See the copyright.txt in the distribution for a
* full listing of individual contributors.
*
* 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 org.hibernate.validator.util;
import java.beans.Introspector;
import java.lang.annotation.Annotation;
import java.lang.annotation.ElementType;
import java.lang.reflect.Constructor;
import java.lang.reflect.Field;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Member;
import java.lang.reflect.Method;
import java.lang.reflect.ParameterizedType;
import java.lang.reflect.Type;
import java.lang.reflect.TypeVariable;
import java.lang.reflect.WildcardType;
import java.security.AccessController;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.HashSet;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Set;
import javax.validation.ValidationException;
import com.googlecode.jtype.TypeUtils;
import org.hibernate.validator.util.privilegedactions.ConstructorInstance;
import org.hibernate.validator.util.privilegedactions.GetAnnotationParameter;
import org.hibernate.validator.util.privilegedactions.GetClassLoader;
import org.hibernate.validator.util.privilegedactions.GetConstructor;
import org.hibernate.validator.util.privilegedactions.GetDeclaredField;
import org.hibernate.validator.util.privilegedactions.GetDeclaredFields;
import org.hibernate.validator.util.privilegedactions.GetDeclaredMethod;
import org.hibernate.validator.util.privilegedactions.GetDeclaredMethods;
import org.hibernate.validator.util.privilegedactions.GetMethod;
import org.hibernate.validator.util.privilegedactions.GetMethodFromPropertyName;
import org.hibernate.validator.util.privilegedactions.GetMethods;
import org.hibernate.validator.util.privilegedactions.LoadClass;
import org.hibernate.validator.util.privilegedactions.NewInstance;
import org.hibernate.validator.util.privilegedactions.SetAccessibility;
/**
* Some reflection utility methods. Where necessary calls will be performed as {@code PrivilegedAction} which is necessary
* for situations where a security manager is in place.
*
* @author Hardy Ferentschik
* @author Gunnar Morling
* @author Kevin Pollet - SERLI - (kevin.pollet@serli.com)
*/
public final class ReflectionHelper {
private static String[] PROPERTY_ACCESSOR_PREFIXES = { "is", "get", "has" };
/**
* Private constructor in order to avoid instantiation.
*/
private ReflectionHelper() {
}
public static ClassLoader getClassLoaderFromContext() {
ClassLoader loader;
GetClassLoader action = GetClassLoader.fromContext();
if ( System.getSecurityManager() != null ) {
loader = AccessController.doPrivileged( action );
}
else {
loader = action.run();
}
return loader;
}
public static ClassLoader getClassLoaderFromClass(Class<?> clazz) {
ClassLoader loader;
GetClassLoader action = GetClassLoader.fromClass( clazz );
if ( System.getSecurityManager() != null ) {
loader = AccessController.doPrivileged( action );
}
else {
loader = action.run();
}
return loader;
}
public static Class<?> loadClass(String className, Class<?> caller) {
LoadClass action = LoadClass.action( className, caller );
if ( System.getSecurityManager() != null ) {
return AccessController.doPrivileged( action );
}
else {
return action.run();
}
}
public static <T> Constructor<T> getConstructor(Class<T> clazz, Class<?>... params) {
Constructor<T> constructor;
GetConstructor<T> action = GetConstructor.action( clazz, params );
if ( System.getSecurityManager() != null ) {
constructor = AccessController.doPrivileged( action );
}
else {
constructor = action.run();
}
return constructor;
}
public static <T> T newInstance(Class<T> clazz, String message) {
T instance;
NewInstance<T> newInstance = NewInstance.action( clazz, message );
if ( System.getSecurityManager() != null ) {
instance = AccessController.doPrivileged( newInstance );
}
else {
instance = newInstance.run();
}
return instance;
}
public static <T> T newConstructorInstance(Constructor<T> constructor, Object... initArgs) {
T instance;
ConstructorInstance<T> newInstance = ConstructorInstance.action( constructor, initArgs );
if ( System.getSecurityManager() != null ) {
instance = AccessController.doPrivileged( newInstance );
}
else {
instance = newInstance.run();
}
return instance;
}
public static <T> T getAnnotationParameter(Annotation annotation, String parameterName, Class<T> type) {
T result;
GetAnnotationParameter<T> action = GetAnnotationParameter.action( annotation, parameterName, type );
if ( System.getSecurityManager() != null ) {
result = AccessController.doPrivileged( action );
}
else {
result = action.run();
}
return result;
}
/**
* Process bean properties getter by applying the JavaBean naming conventions.
*
* @param member the member for which to get the property name.
*
* @return The bean method name with the "is" or "get" prefix stripped off, <code>null</code>
* the method name id not according to the JavaBeans standard.
*/
public static String getPropertyName(Member member) {
String name = null;
if ( member instanceof Field ) {
name = member.getName();
}
if ( member instanceof Method ) {
String methodName = member.getName();
for ( String prefix : PROPERTY_ACCESSOR_PREFIXES ) {
if ( methodName.startsWith( prefix ) ) {
name = Introspector.decapitalize( methodName.substring( prefix.length() ) );
}
}
}
return name;
}
/**
* Checks whether the given method's name is a valid JavaBeans getter name,
* meaning it starts with "is" or "has".
*
* @param member The method of interest.
*
* @return True, if the given method is a JavaBeans getter method, false
* otherwise.
*/
public static boolean isGetterMethod(Method member) {
return getPropertyName( member ) != null;
}
/**
* Checks whether the property with the specified name and type exists on the given class.
*
* @param clazz The class to check for the property. Cannot be {@code null}.
* @param property The property name without 'is', 'get' or 'has'. Cannot be {@code null} or empty.
* @param elementType The element type. Either {@code ElementType.FIELD} or {@code ElementType METHOD}.
*
* @return {@code true} is the property and can be access via the specified type, {@code false} otherwise.
*/
public static boolean propertyExists(Class<?> clazz, String property, ElementType elementType) {
return getMember( clazz, property, elementType ) != null;
}
/**
* Returns the member with the given name and type.
*
* @param clazz The class from which to retrieve the member. Cannot be {@code null}.
* @param property The property name without 'is', 'get' or 'has'. Cannot be {@code null} or empty.
* @param elementType The element type. Either {@code ElementType.FIELD} or {@code ElementType METHOD}.
*
* @return the member which matching the name and type or {@code null} if no such member exists.
*/
public static Member getMember(Class<?> clazz, String property, ElementType elementType) {
if ( clazz == null ) {
throw new IllegalArgumentException( "The class cannot be null" );
}
if ( property == null || property.length() == 0 ) {
throw new IllegalArgumentException( "Property name cannot be null or empty" );
}
if ( !( ElementType.FIELD.equals( elementType ) || ElementType.METHOD.equals( elementType ) ) ) {
throw new IllegalArgumentException( "Element type has to be FIELD or METHOD" );
}
Member member = null;
if ( ElementType.FIELD.equals( elementType ) ) {
GetDeclaredField action = GetDeclaredField.action( clazz, property );
if ( System.getSecurityManager() != null ) {
member = AccessController.doPrivileged( action );
}
else {
member = action.run();
}
}
else {
String methodName = property.substring( 0, 1 ).toUpperCase() + property.substring( 1 );
for ( String prefix : PROPERTY_ACCESSOR_PREFIXES ) {
GetMethod action = GetMethod.action( clazz, prefix + methodName );
if ( System.getSecurityManager() != null ) {
member = AccessController.doPrivileged( action );
}
else {
member = action.run();
}
if ( member != null ) {
break;
}
}
}
return member;
}
/**
* Returns the type of the field of return type of a method.
*
* @param member the member for which to get the type.
*
* @return Returns the type of the field of return type of a method.
*/
public static Class<?> getType(Member member) {
Class<?> type = null;
if ( member instanceof Field ) {
type = ( (Field) member ).getType();
}
if ( member instanceof Method ) {
type = ( (Method) member ).getReturnType();
}
return type;
}
/**
* @param member The <code>Member</code> instance for which to retrieve the type.
*
* @return Returns the <code>Type</code> of the given <code>Field</code> or <code>Method</code>.
*
* @throws IllegalArgumentException in case <code>member</code> is not a <code>Field</code> or <code>Method</code>.
*/
public static Type typeOf(Member member) {
Type type;
if ( member instanceof Field ) {
type = ( (Field) member ).getGenericType();
}
else if ( member instanceof Method ) {
type = ( (Method) member ).getGenericReturnType();
}
else {
throw new IllegalArgumentException( "Member " + member + " is neither a field nor a method" );
}
if ( type instanceof TypeVariable ) {
type = TypeUtils.getErasedType( type );
}
return type;
}
/**
* Returns the type of the parameter of the given method with the given parameter index.
*
* @param method The method of interest.
* @param parameterIndex The index of the parameter for which the type should be returned.
*
* @return The erased type.
*/
public static Type typeOf(Method method, int parameterIndex) {
Type type = method.getGenericParameterTypes()[parameterIndex];
if ( type instanceof TypeVariable ) {
type = TypeUtils.getErasedType( type );
}
return type;
}
public static Object getValue(Member member, Object object) {
Object value = null;
if ( member instanceof Method ) {
Method method = (Method) member;
try {
value = method.invoke( object );
}
catch ( IllegalAccessException e ) {
throw new ValidationException( "Unable to access " + method.getName(), e );
}
catch ( InvocationTargetException e ) {
throw new ValidationException( "Unable to access " + method.getName(), e );
}
}
else if ( member instanceof Field ) {
Field field = (Field) member;
try {
value = field.get( object );
}
catch ( IllegalAccessException e ) {
throw new ValidationException( "Unable to access " + field.getName(), e );
}
}
return value;
}
public static void setAccessibility(Member member) {
SetAccessibility action = SetAccessibility.action( member );
if ( System.getSecurityManager() != null ) {
AccessController.doPrivileged( action );
}
else {
action.run();
}
}
/**
* Determines the type of elements of an <code>Iterable</code>, array or the value of a <code>Map</code>.
*
* @param type the type to inspect
*
* @return Returns the type of elements of an <code>Iterable</code>, array or the value of a <code>Map</code>. <code>
* null</code> is returned in case the type is not indexable (in the context of JSR 303).
*/
public static Type getIndexedType(Type type) {
Type indexedType = null;
if ( isIterable( type ) && type instanceof ParameterizedType ) {
ParameterizedType paramType = (ParameterizedType) type;
indexedType = paramType.getActualTypeArguments()[0];
}
else if ( isMap( type ) && type instanceof ParameterizedType ) {
ParameterizedType paramType = (ParameterizedType) type;
indexedType = paramType.getActualTypeArguments()[1];
}
else if ( TypeUtils.isArray( type ) ) {
indexedType = TypeUtils.getComponentType( type );
}
return indexedType;
}
/**
* @param type the type to check.
*
* @return Returns <code>true</code> if <code>type</code> is a iterable type, <code>false</code> otherwise.
*/
public static boolean isIterable(Type type) {
if ( type instanceof Class && Iterable.class.isAssignableFrom( (Class<?>) type ) ) {
return true;
}
if ( type instanceof ParameterizedType ) {
return isIterable( ( (ParameterizedType) type ).getRawType() );
}
if ( type instanceof WildcardType ) {
Type[] upperBounds = ( (WildcardType) type ).getUpperBounds();
return upperBounds.length != 0 && isIterable( upperBounds[0] );
}
return false;
}
/**
* @param type the type to check.
*
* @return Returns <code>true</code> if <code>type</code> is implementing <code>Map</code>, <code>false</code> otherwise.
*/
public static boolean isMap(Type type) {
if ( type instanceof Class && Map.class.isAssignableFrom( (Class<?>) type ) ) {
return true;
}
if ( type instanceof ParameterizedType ) {
return isMap( ( (ParameterizedType) type ).getRawType() );
}
if ( type instanceof WildcardType ) {
Type[] upperBounds = ( (WildcardType) type ).getUpperBounds();
return upperBounds.length != 0 && isMap( upperBounds[0] );
}
return false;
}
/**
* @param type the type to check.
*
* @return Returns <code>true</code> if <code>type</code> is implementing <code>List</code>, <code>false</code> otherwise.
*/
public static boolean isList(Type type) {
if ( type instanceof Class && List.class.isAssignableFrom( (Class<?>) type ) ) {
return true;
}
if ( type instanceof ParameterizedType ) {
return isList( ( (ParameterizedType) type ).getRawType() );
}
if ( type instanceof WildcardType ) {
Type[] upperBounds = ( (WildcardType) type ).getUpperBounds();
return upperBounds.length != 0 && isList( upperBounds[0] );
}
return false;
}
/**
* Tries to retrieve the indexed value from the specified object.
*
* @param value The object from which to retrieve the indexed value. The object has to be non <code>null</null> and
* either a collection or array.
* @param index The index. The index does not have to be numerical. <code>value</code> could also be a map in which
* case the index could also be a string key.
*
* @return The indexed value or <code>null</code> if <code>value</code> is <code>null</code> or not a collection or array.
* <code>null</code> is also returned in case the index does not exist.
*/
public static Object getIndexedValue(Object value, Integer index) {
if ( value == null ) {
return null;
}
Iterator<?> iter;
Type type = value.getClass();
if ( isIterable( type ) ) {
iter = ( (Iterable<?>) value ).iterator();
}
else if ( TypeUtils.isArray( type ) ) {
List<?> arrayList = Arrays.asList( (Object) value );
iter = arrayList.iterator();
}
else {
return null;
}
int i = 0;
Object o;
while ( iter.hasNext() ) {
o = iter.next();
if ( i == index ) {
return o;
}
i++;
}
return null;
}
/**
* Tries to retrieve the mapped value from the specified object.
*
* @param value The object from which to retrieve the mapped value. The object has to be non {@code null} and
* must implement the @{code Map} interface.
* @param key The map key. index.
*
* @return The mapped value or {@code null} if {@code value} is {@code null} or not implementing @{code Map}.
*/
public static Object getMappedValue(Object value, Object key) {
if ( !( value instanceof Map ) ) {
return null;
}
Map<?, ?> map = (Map<?, ?>) value;
//noinspection SuspiciousMethodCalls
return map.get( key );
}
/**
* Returns the declared field with the specified name or {@code null} if it does not exist.
*
* @param clazz The class to check.
* @param fieldName The field name.
*
* @return Returns the declared field with the specified name or {@code null} if it does not exist.
*/
public static Field getDeclaredField(Class<?> clazz, String fieldName) {
GetDeclaredField action = GetDeclaredField.action( clazz, fieldName );
final Field field;
if ( System.getSecurityManager() != null ) {
field = AccessController.doPrivileged( action );
}
else {
field = action.run();
}
return field;
}
/**
* Checks whether the specified class contains a declared field with the given name.
*
* @param clazz The class to check.
* @param fieldName The field name.
*
* @return Returns {@code true} if the field exists, {@code false} otherwise.
*/
public static boolean containsDeclaredField(Class<?> clazz, String fieldName) {
return getDeclaredField( clazz, fieldName ) != null;
}
/**
* Returns the fields of the specified class.
*
* @param clazz The class for which to retrieve the fields.
*
* @return Returns the fields for this class.
*/
public static Field[] getDeclaredFields(Class<?> clazz) {
GetDeclaredFields action = GetDeclaredFields.action( clazz );
final Field[] fields;
if ( System.getSecurityManager() != null ) {
fields = AccessController.doPrivileged( action );
}
else {
fields = action.run();
}
return fields;
}
/**
* Returns the method with the specified property name or {@code null} if it does not exist. This method will
* prepend 'is' and 'get' to the property name and capitalize the first letter.
*
* @param clazz The class to check.
* @param methodName The property name.
*
* @return Returns the method with the specified property or {@code null} if it does not exist.
*/
public static Method getMethodFromPropertyName(Class<?> clazz, String methodName) {
Method method;
GetMethodFromPropertyName action = GetMethodFromPropertyName.action( clazz, methodName );
if ( System.getSecurityManager() != null ) {
method = AccessController.doPrivileged( action );
}
else {
method = action.run();
}
return method;
}
/**
* Checks whether the specified class contains a method for the specified property.
*
* @param clazz The class to check.
* @param property The property name.
*
* @return Returns {@code true} if the method exists, {@code false} otherwise.
*/
public static boolean containsMethodWithPropertyName(Class<?> clazz, String property) {
return getMethodFromPropertyName( clazz, property ) != null;
}
/**
* Returns the method with the specified name or {@code null} if it does not exist.
*
* @param clazz The class to check.
* @param methodName The method name.
*
* @return Returns the method with the specified property or {@code null} if it does not exist.
*/
public static Method getMethod(Class<?> clazz, String methodName) {
Method method;
GetMethod action = GetMethod.action( clazz, methodName );
if ( System.getSecurityManager() != null ) {
method = AccessController.doPrivileged( action );
}
else {
method = action.run();
}
return method;
}
/**
* Returns the declared method with the specified name and parameter types or {@code null} if
* it does not exist.
*
* @param clazz The class to check.
* @param methodName The method name.
* @param parameterTypes The method parameter types.
*
* @return Returns the declared method with the specified name or {@code null} if it does not exist.
*/
public static Method getDeclaredMethod(Class<?> clazz, String methodName, Class<?>... parameterTypes) {
Method method;
GetDeclaredMethod action = GetDeclaredMethod.action( clazz, methodName, parameterTypes );
if ( System.getSecurityManager() != null ) {
method = AccessController.doPrivileged( action );
}
else {
method = action.run();
}
return method;
}
/**
* Returns the declared methods of the specified class.
*
* @param clazz The class for which to retrieve the methods.
*
* @return Returns the declared methods for this class.
*/
public static Method[] getDeclaredMethods(Class<?> clazz) {
GetDeclaredMethods action = GetDeclaredMethods.action( clazz );
final Method[] methods;
if ( System.getSecurityManager() != null ) {
methods = AccessController.doPrivileged( action );
}
else {
methods = action.run();
}
return methods;
}
/**
* Returns the methods of the specified class (include inherited methods).
*
* @param clazz The class for which to retrieve the methods.
*
* @return Returns the methods for this class.
*/
public static Method[] getMethods(Class<?> clazz) {
GetMethods action = GetMethods.action( clazz );
final Method[] methods;
if ( System.getSecurityManager() != null ) {
methods = AccessController.doPrivileged( action );
}
else {
methods = action.run();
}
return methods;
}
/**
* Checks, whether the given methods have the same signature, which is the
* case if they have the same name, parameter count and types.
*
* @param method1 A first method.
* @param method2 A second method.
*
* @return True, if the methods have the same signature, false otherwise.
*/
public static boolean haveSameSignature(Method method1, Method method2) {
if ( method1 == null || method2 == null ) {
throw new IllegalArgumentException( "method1 and method2 must not be null" );
}
return
method1.getName().equals( method2.getName() ) &&
Arrays.equals( method1.getGenericParameterTypes(), method2.getGenericParameterTypes() );
}
/**
* Returns the autoboxed type of a primitive type.
*
* @param primitiveType the primitive type
*
* @return the autoboxed type of a primitive type.
*
* @throws IllegalArgumentException in case the parameter {@code primitiveType} does not represent a primitive type.
*/
public static Class<?> boxedType(Type primitiveType) {
if ( !( primitiveType instanceof Class ) && !( (Class<?>) primitiveType ).isPrimitive() ) {
throw new IllegalArgumentException( primitiveType.getClass() + "has to be a primitive type" );
}
if ( primitiveType == boolean.class ) {
return Boolean.class;
}
else if ( primitiveType == char.class ) {
return Character.class;
}
else if ( primitiveType == double.class ) {
return Double.class;
}
else if ( primitiveType == float.class ) {
return Float.class;
}
else if ( primitiveType == long.class ) {
return Long.class;
}
else if ( primitiveType == int.class ) {
return Integer.class;
}
else if ( primitiveType == short.class ) {
return Short.class;
}
else if ( primitiveType == byte.class ) {
return Byte.class;
}
else {
throw new RuntimeException( "Unhandled primitive type." );
}
}
/**
* Get all superclasses and optionally interfaces recursively.
*
* @param clazz The class to start the search with.
* @param includeInterfaces whether or not to include interfaces
*
* @return List of all super classes and interfaces of {@code clazz}. The list contains the class itself! The empty
* list is returned if {@code clazz} is {@code null}.
*/
public static List<Class<?>> computeClassHierarchy(Class<?> clazz, boolean includeInterfaces) {
List<Class<?>> classes = new ArrayList<Class<?>>();
computeClassHierarchy( clazz, classes, includeInterfaces );
return classes;
}
/**
* Get all superclasses and interfaces recursively.
*
* @param clazz The class to start the search with
* @param classes List of classes to which to add all found super classes and interfaces
* @param includeInterfaces whether or not to include interfaces
*/
private static void computeClassHierarchy(Class<?> clazz, List<Class<?>> classes, boolean includeInterfaces) {
for ( Class<?> current = clazz; current != null; current = current.getSuperclass() ) {
if ( classes.contains( current ) ) {
return;
}
classes.add( current );
if ( includeInterfaces ) {
for ( Class<?> currentInterface : current.getInterfaces() ) {
computeClassHierarchy( currentInterface, classes, includeInterfaces );
}
}
}
}
/**
* Get all interfaces a class directly implements.
*
* @param clazz The class for which to find the interfaces
*
* @return Set of all interfaces {@code clazz} implements. The empty list is returned if {@code clazz} does not
* implement any interfaces or {@code clazz} is {@code null}
*/
public static Set<Class<?>> computeAllImplementedInterfaces(Class<?> clazz) {
Set<Class<?>> classes = new HashSet<Class<?>>();
computeAllImplementedInterfaces( clazz, classes );
return classes;
}
private static void computeAllImplementedInterfaces(Class<?> clazz, Set<Class<?>> classes) {
if ( clazz == null ) {
return;
}
for ( Class<?> currentInterface : clazz.getInterfaces() ) {
classes.add( currentInterface );
computeAllImplementedInterfaces( currentInterface, classes );
}
}
}