// Copyright (c) 2003-present, Jodd Team (http://jodd.org) // All rights reserved. // // Redistribution and use in source and binary forms, with or without // modification, are permitted provided that the following conditions are met: // // 1. Redistributions of source code must retain the above copyright notice, // this list of conditions and the following disclaimer. // // 2. Redistributions in binary form must reproduce the above copyright // notice, this list of conditions and the following disclaimer in the // documentation and/or other materials provided with the distribution. // // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" // AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE // IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE // ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE // LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR // CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF // SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS // INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN // CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) // ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE // POSSIBILITY OF SUCH DAMAGE. package jodd.util; import jodd.util.cl.ClassLoaderStrategy; import java.lang.annotation.Annotation; import java.lang.reflect.AccessibleObject; import java.lang.reflect.Array; import java.lang.reflect.Constructor; import java.lang.reflect.Field; import java.lang.reflect.GenericArrayType; import java.lang.reflect.InvocationTargetException; import java.lang.reflect.Member; import java.lang.reflect.Method; import java.lang.reflect.Modifier; import java.lang.reflect.ParameterizedType; import java.lang.reflect.Type; import java.lang.reflect.TypeVariable; import java.lang.reflect.WildcardType; import java.util.ArrayList; import java.util.Collection; import java.util.Collections; import java.util.HashMap; import java.util.HashSet; import java.util.LinkedHashSet; import java.util.List; import java.util.Map; import java.util.Set; /** * Class utilities. */ public class ClassUtil { /** Empty class array. */ public static final Class[] EMPTY_CLASS_ARRAY = new Class[0]; public static final String METHOD_GET_PREFIX = "get"; public static final String METHOD_IS_PREFIX = "is"; public static final String METHOD_SET_PREFIX = "set"; // ---------------------------------------------------------------- method0 private static Method _getMethod0; static { try { _getMethod0 = Class.class.getDeclaredMethod("getMethod0", String.class, Class[].class); _getMethod0.setAccessible(true); } catch (Exception ignore) { try { _getMethod0 = Class.class.getMethod("getMethod", String.class, Class[].class); } catch (Exception ignored) { _getMethod0 = null; } } } /** * Invokes private <code>Class.getMethod0()</code> without throwing <code>NoSuchMethodException</code>. * Returns only public methods or <code>null</code> if method not found. Since no exception is * throwing, it works faster. * * @param c class to inspect * @param name name of method to find * @param parameterTypes parameter types * @return founded method, or null */ public static Method getMethod0(Class c, String name, Class... parameterTypes) { try { return (Method) _getMethod0.invoke(c, name, parameterTypes); } catch (Exception ignore) { return null; } } // ---------------------------------------------------------------- find method /** * Returns method from an object, matched by name. This may be considered as * a slow operation, since methods are matched one by one. * Returns only accessible methods. * Only first method is matched. * * @param c class to examine * @param methodName Full name of the method. * @return null if method not found */ public static Method findMethod(Class c, String methodName) { return findDeclaredMethod(c, methodName, true); } /** * @see #findMethod(Class, String) */ public static Method findDeclaredMethod(Class c, String methodName) { return findDeclaredMethod(c, methodName, false); } private static Method findDeclaredMethod(Class c, String methodName, boolean publicOnly) { if ((methodName == null) || (c == null)) { return null; } Method[] ms = publicOnly ? c.getMethods() : c.getDeclaredMethods(); for (Method m : ms) { if (m.getName().equals(methodName)) { return m; } } return null; } // ---------------------------------------------------------------- find ctor /** * Finds constructor with given parameter types. First matched ctor is returned. */ public static <T> Constructor<T> findConstructor(Class<T> clazz, Class<?>... parameterTypes) { final Constructor<?>[] constructors = clazz.getConstructors(); Class<?>[] pts; for (Constructor<?> constructor : constructors) { pts = constructor.getParameterTypes(); if (isAllAssignableFrom(pts, parameterTypes)) { return (Constructor<T>) constructor; } } return null; } /** * Returns {@code true} if all types are assignable from the other array of types. */ public static boolean isAllAssignableFrom(Class<?>[] typesTarget, Class<?>[] typesFrom) { if (typesTarget.length == typesFrom.length) { for (int i = 0; i < typesTarget.length; i++) { if (!typesTarget[i].isAssignableFrom(typesFrom[i])) { return false; } } return true; } return false; } // ---------------------------------------------------------------- classes /** * Returns classes from array of objects. It accepts {@code null} * values. */ public static Class[] getClasses(Object... objects) { if (objects.length == 0) { return EMPTY_CLASS_ARRAY; } Class[] result = new Class[objects.length]; for (int i = 0; i < objects.length; i++) { if (objects[i] != null) { result[i] = objects[i].getClass(); } } return result; } // ---------------------------------------------------------------- match classes /** * Safe version of <code>isAssignableFrom</code> method that * returns <code>false</code> if one of the arguments is <code>null</code>. */ public static boolean isTypeOf(Class<?> lookupClass, Class<?> targetClass) { if (targetClass == null || lookupClass == null) { return false; } return targetClass.isAssignableFrom(lookupClass); } /** * Safe version of <code>isInstance</code>, returns <code>false</code> * if any of the arguments is <code>null</code>. */ public static boolean isInstanceOf(Object object, Class target) { if (object == null || target == null) { return false; } return target.isInstance(object); } /** * Resolves all interfaces of a type. No duplicates are returned. * Direct interfaces are prior the interfaces of subclasses in * the returned array. */ public static Class[] resolveAllInterfaces(Class type) { Set<Class> bag = new LinkedHashSet<>(); _resolveAllInterfaces(type, bag); return bag.toArray(new Class[bag.size()]); } private static void _resolveAllInterfaces(Class type, Set<Class> bag) { // add types interfaces Class[] interfaces = type.getInterfaces(); Collections.addAll(bag, interfaces); // resolve interfaces of each interface for (Class iface : interfaces) { _resolveAllInterfaces(iface, bag); } // continue with super type Class superClass = type.getSuperclass(); if (superClass == null) { return; } if (superClass == Object.class) { return; } _resolveAllInterfaces(type.getSuperclass(), bag); } /** * Resolves all super classes, from top (direct subclass) to down. <code>Object</code> * class is not included in the list. */ public static Class[] resolveAllSuperclasses(Class type) { List<Class> list = new ArrayList<>(); while (true) { type = type.getSuperclass(); if ((type == null) || (type == Object.class)) { break; } list.add(type); } return list.toArray(new Class[list.size()]); } // ---------------------------------------------------------------- accessible methods /** * Returns array of all methods that are accessible from given class. * @see #getAccessibleMethods(Class, Class) */ public static Method[] getAccessibleMethods(Class clazz) { return getAccessibleMethods(clazz, Object.class); } /** * Returns array of all methods that are accessible from given class, upto limit * (usually <code>Object.class</code>). Abstract methods are ignored. */ public static Method[] getAccessibleMethods(Class clazz, Class limit) { Package topPackage = clazz.getPackage(); List<Method> methodList = new ArrayList<>(); int topPackageHash = topPackage == null ? 0 : topPackage.hashCode(); boolean top = true; do { if (clazz == null) { break; } Method[] declaredMethods = clazz.getDeclaredMethods(); for (Method method : declaredMethods) { if (Modifier.isVolatile(method.getModifiers())) { continue; } // if (Modifier.isAbstract(method.getModifiers())) { // continue; // } if (top) { // add all top declared methods methodList.add(method); continue; } int modifier = method.getModifiers(); if (Modifier.isPrivate(modifier)) { continue; // ignore super private methods } if (Modifier.isAbstract(modifier)) { // ignore super abstract methods continue; } if (Modifier.isPublic(modifier)) { addMethodIfNotExist(methodList, method); // add super public methods continue; } if (Modifier.isProtected(modifier)) { addMethodIfNotExist(methodList, method); // add super protected methods continue; } // add super default methods from the same package Package pckg = method.getDeclaringClass().getPackage(); int pckgHash = pckg == null ? 0 : pckg.hashCode(); if (pckgHash == topPackageHash) { addMethodIfNotExist(methodList, method); } } top = false; } while ((clazz = clazz.getSuperclass()) != limit); Method[] methods = new Method[methodList.size()]; for (int i = 0; i < methods.length; i++) { methods[i] = methodList.get(i); } return methods; } private static void addMethodIfNotExist(List<Method> allMethods, Method newMethod) { for (Method m : allMethods) { if (compareSignatures(m, newMethod)) { return; } } allMethods.add(newMethod); } // ---------------------------------------------------------------- accessible fields public static Field[] getAccessibleFields(Class clazz) { return getAccessibleFields(clazz, Object.class); } public static Field[] getAccessibleFields(Class clazz, Class limit) { Package topPackage = clazz.getPackage(); List<Field> fieldList = new ArrayList<>(); int topPackageHash = topPackage == null ? 0 : topPackage.hashCode(); boolean top = true; do { if (clazz == null) { break; } Field[] declaredFields = clazz.getDeclaredFields(); for (Field field : declaredFields) { if (top) { // add all top declared fields fieldList.add(field); continue; } int modifier = field.getModifiers(); if (Modifier.isPrivate(modifier)) { continue; // ignore super private fields } if (Modifier.isPublic(modifier)) { addFieldIfNotExist(fieldList, field); // add super public methods continue; } if (Modifier.isProtected(modifier)) { addFieldIfNotExist(fieldList, field); // add super protected methods continue; } // add super default methods from the same package Package pckg = field.getDeclaringClass().getPackage(); int pckgHash = pckg == null ? 0 : pckg.hashCode(); if (pckgHash == topPackageHash) { addFieldIfNotExist(fieldList, field); } } top = false; } while ((clazz = clazz.getSuperclass()) != limit); Field[] fields = new Field[fieldList.size()]; for (int i = 0; i < fields.length; i++) { fields[i] = fieldList.get(i); } return fields; } private static void addFieldIfNotExist(List<Field> allFields, Field newField) { for (Field f : allFields) { if (compareSignatures(f, newField)) { return; } } allFields.add(newField); } // ---------------------------------------------------------------- supported methods public static Method[] getSupportedMethods(Class clazz) { return getSupportedMethods(clazz, Object.class); } /** * Returns a <code>Method</code> array of the methods to which instances of the specified * respond except for those methods defined in the class specified by limit * or any of its superclasses. Note that limit is usually used to eliminate * them methods defined by <code>java.lang.Object</code>. If limit is <code>null</code> then all * methods are returned. */ public static Method[] getSupportedMethods(Class clazz, Class limit) { ArrayList<Method> supportedMethods = new ArrayList<>(); for (Class c = clazz; c != limit; c = c.getSuperclass()) { Method[] methods = c.getDeclaredMethods(); for (Method method : methods) { boolean found = false; for (Method supportedMethod : supportedMethods) { if (compareSignatures(method, supportedMethod)) { found = true; break; } } if (!found) { supportedMethods.add(method); } } } return supportedMethods.toArray(new Method[supportedMethods.size()]); } public static Field[] getSupportedFields(Class clazz) { return getSupportedFields(clazz, Object.class); } public static Field[] getSupportedFields(Class clazz, Class limit) { ArrayList<Field> supportedFields = new ArrayList<>(); for (Class c = clazz; c != limit; c = c.getSuperclass()) { Field[] fields = c.getDeclaredFields(); for (Field field : fields) { boolean found = false; for (Field supportedField : supportedFields) { if (compareSignatures(field, supportedField)) { found = true; break; } } if (!found) { supportedFields.add(field); } } } return supportedFields.toArray(new Field[supportedFields.size()]); } // ---------------------------------------------------------------- compare /** * Compares method declarations: signature and return types. */ public static boolean compareDeclarations(Method first, Method second) { if (first.getReturnType() != second.getReturnType()) { return false; } return compareSignatures(first, second); } /** * Compares method signatures: names and parameters. */ public static boolean compareSignatures(Method first, Method second) { if (!first.getName().equals(second.getName())) { return false; } return compareParameters(first.getParameterTypes(), second.getParameterTypes()); } /** * Compares constructor signatures: names and parameters. */ public static boolean compareSignatures(Constructor first, Constructor second) { if (!first.getName().equals(second.getName())) { return false; } return compareParameters(first.getParameterTypes(), second.getParameterTypes()); } public static boolean compareSignatures(Field first, Field second) { return first.getName().equals(second.getName()); } /** * Compares classes, usually method or ctor parameters. */ public static boolean compareParameters(Class[] first, Class[] second) { if (first.length != second.length) { return false; } for (int i = 0; i < first.length; i++) { if (first[i] != second[i]) { return false; } } return true; } // ---------------------------------------------------------------- force /** * Suppress access check against a reflection object. SecurityException is silently ignored. * Checks first if the object is already accessible. */ public static void forceAccess(AccessibleObject accObject) { if (accObject.isAccessible()) { return; } try { accObject.setAccessible(true); } catch (SecurityException sex) { // ignore } } // ---------------------------------------------------------------- is public /** * Returns <code>true</code> if class member is public. */ public static boolean isPublic(Member member) { return Modifier.isPublic(member.getModifiers()); } /** * Returns <code>true</code> if class member is public and if its declaring class is also public. */ public static boolean isPublicPublic(Member member) { if (Modifier.isPublic(member.getModifiers())) { if (Modifier.isPublic(member.getDeclaringClass().getModifiers())) { return true; } } return false; } /** * Returns <code>true</code> if class is public. */ public static boolean isPublic(Class c) { return Modifier.isPublic(c.getModifiers()); } // ---------------------------------------------------------------- create /** * Creates new instance of given class with given optional arguments. */ @SuppressWarnings("unchecked") public static <T> T newInstance(Class<T> clazz, Object... params) throws InstantiationException, IllegalAccessException, InvocationTargetException { if (params.length == 0) { return newInstance(clazz); } final Class<?>[] paramTypes = getClasses(params); final Constructor<?> constructor = findConstructor(clazz, paramTypes); if (constructor == null) { throw new InstantiationException("No constructor matched parameter types."); } return (T) constructor.newInstance(params); } /** * Creates new instances including for common mutable classes that do not have a default constructor. * more user-friendly. It examines if class is a map, list, * String, Character, Boolean or a Number. Immutable instances are cached and not created again. * Arrays are also created with no elements. Note that this bunch of <code>if</code> blocks * is faster then using a <code>HashMap</code>. */ @SuppressWarnings("unchecked") public static <T> T newInstance(Class<T> type) throws IllegalAccessException, InstantiationException { if (type.isPrimitive()) { if (type == int.class) { return (T) Integer.valueOf(0); } if (type == long.class) { return (T) Long.valueOf(0); } if (type == boolean.class) { return (T) Boolean.FALSE; } if (type == float.class) { return (T) Float.valueOf(0); } if (type == double.class) { return (T) Double.valueOf(0); } if (type == byte.class) { return (T) Byte.valueOf((byte) 0); } if (type == short.class) { return (T) Short.valueOf((short) 0); } if (type == char.class) { return (T) Character.valueOf((char) 0); } throw new IllegalArgumentException("Invalid primitive: " + type); } if (type == Integer.class) { return (T) Integer.valueOf(0); } if (type == String.class) { return (T) StringPool.EMPTY; } if (type == Long.class) { return (T) Long.valueOf(0); } if (type == Boolean.class) { return (T) Boolean.FALSE; } if (type == Float.class) { return (T) Float.valueOf(0); } if (type == Double.class) { return (T) Double.valueOf(0); } if (type == Map.class) { return (T) new HashMap(); } if (type == List.class) { return (T) new ArrayList(); } if (type == Set.class) { return (T) new HashSet(); } if (type == Collection.class) { return (T) new ArrayList(); } if (type == Byte.class) { return (T) Byte.valueOf((byte) 0); } if (type == Short.class) { return (T) Short.valueOf((short) 0); } if (type == Character.class) { return (T) Character.valueOf((char) 0); } if (type.isEnum()) { return type.getEnumConstants()[0]; } if (type.isArray()) { return (T) Array.newInstance(type.getComponentType(), 0); } return type.newInstance(); } // ---------------------------------------------------------------- misc /** * Returns <code>true</code> if the first member is accessible from second one. */ public static boolean isAssignableFrom(Member member1, Member member2) { return member1.getDeclaringClass().isAssignableFrom(member2.getDeclaringClass()); } /** * Returns all superclasses. */ public static Class[] getSuperclasses(Class type) { int i = 0; for (Class x = type.getSuperclass(); x != null; x = x.getSuperclass()) { i++; } Class[] result = new Class[i]; i = 0; for (Class x = type.getSuperclass(); x != null; x = x.getSuperclass()) { result[i] = x; i++; } return result; } /** * Returns <code>true</code> if method is user defined and not defined in <code>Object</code> class. */ public static boolean isUserDefinedMethod(final Method method) { return method.getDeclaringClass() != Object.class; } /** * Returns <code>true</code> if method defined in <code>Object</code> class. */ public static boolean isObjectMethod(final Method method) { return method.getDeclaringClass() == Object.class; } /** * Returns <code>true</code> if method is a bean property. */ public static boolean isBeanProperty(Method method) { if (isObjectMethod(method)) { return false; } String methodName = method.getName(); Class returnType = method.getReturnType(); Class[] paramTypes = method.getParameterTypes(); if (methodName.startsWith(METHOD_GET_PREFIX)) { // getter method must starts with 'get' and it is not getClass() if ((returnType != null) && (paramTypes.length == 0)) { // getter must have a return type and no arguments return true; } } else if (methodName.startsWith(METHOD_IS_PREFIX)) { // ister must starts with 'is' if ((returnType != null) && (paramTypes.length == 0)) { // ister must have return type and no arguments return true; } } else if (methodName.startsWith(METHOD_SET_PREFIX)) { // setter must start with a 'set' if (paramTypes.length == 1) { // setter must have just one argument return true; } } return false; } /** * Returns <code>true</code> if method is bean getter. */ public static boolean isBeanPropertyGetter(Method method) { return getBeanPropertyGetterPrefixLength(method) != 0; } private static int getBeanPropertyGetterPrefixLength(Method method) { if (isObjectMethod(method)) { return 0; } String methodName = method.getName(); Class returnType = method.getReturnType(); Class[] paramTypes = method.getParameterTypes(); if (methodName.startsWith(METHOD_GET_PREFIX)) { // getter method must starts with 'get' and it is not getClass() if ((returnType != null) && (paramTypes.length == 0)) { // getter must have a return type and no arguments return 3; } } else if (methodName.startsWith(METHOD_IS_PREFIX)) { // ister must starts with 'is' if ((returnType != null) && (paramTypes.length == 0)) { // ister must have return type and no arguments return 2; } } return 0; } /** * Returns property name from a getter method. * Returns <code>null</code> if method is not a real getter. */ public static String getBeanPropertyGetterName(Method method) { int prefixLength = getBeanPropertyGetterPrefixLength(method); if (prefixLength == 0) { return null; } String methodName = method.getName().substring(prefixLength); return StringUtil.decapitalize(methodName); } /** * Returns <code>true</code> if method is bean setter. */ public static boolean isBeanPropertySetter(Method method) { return getBeanPropertySetterPrefixLength(method) != 0; } private static int getBeanPropertySetterPrefixLength(Method method) { if (isObjectMethod(method)) { return 0; } String methodName = method.getName(); Class[] paramTypes = method.getParameterTypes(); if (methodName.startsWith(METHOD_SET_PREFIX)) { // setter must start with a 'set' if (paramTypes.length == 1) { // setter must have just one argument return 3; } } return 0; } /** * Returns beans property setter name or <code>null</code> if method is not a real setter. */ public static String getBeanPropertySetterName(Method method) { int prefixLength = getBeanPropertySetterPrefixLength(method); if (prefixLength == 0) { return null; } String methodName = method.getName().substring(prefixLength); return StringUtil.decapitalize(methodName); } // ---------------------------------------------------------------- generics /** * Returns single component type. Index is used when type consist of many * components. If negative, index will be calculated from the end of the * returned array. Returns <code>null</code> if component type * does not exist or if index is out of bounds. * * @see #getComponentTypes(java.lang.reflect.Type) */ public static Class getComponentType(Type type, int index) { return getComponentType(type, null, index); } /** * Returns single component type for given type and implementation. * Index is used when type consist of many * components. If negative, index will be calculated from the end of the * returned array. Returns <code>null</code> if component type * does not exist or if index is out of bounds. * <p> * * @see #getComponentTypes(java.lang.reflect.Type, Class) */ public static Class getComponentType(Type type, Class implClass, int index) { Class[] componentTypes = getComponentTypes(type, implClass); if (componentTypes == null) { return null; } if (index < 0) { index += componentTypes.length; } if (index >= componentTypes.length) { return null; } return componentTypes[index]; } /** * @see #getComponentTypes(java.lang.reflect.Type, Class) */ public static Class[] getComponentTypes(Type type) { return getComponentTypes(type, null); } /** * Returns all component types of the given type. * For example the following types all have the * component-type MyClass: * <ul> * <li>MyClass[]</li> * <li>List<MyClass></li> * <li>Foo<? extends MyClass></li> * <li>Bar<? super MyClass></li> * <li><T extends MyClass> T[]</li> * </ul> */ public static Class[] getComponentTypes(Type type, Class implClass) { if (type instanceof Class) { Class clazz = (Class) type; if (clazz.isArray()) { return new Class[] {clazz.getComponentType()}; } } else if (type instanceof ParameterizedType) { ParameterizedType pt = (ParameterizedType) type; Type[] generics = pt.getActualTypeArguments(); if (generics.length == 0) { return null; } Class[] types = new Class[generics.length]; for (int i = 0; i < generics.length; i++) { types[i] = getRawType(generics[i], implClass); } return types; } else if (type instanceof GenericArrayType) { GenericArrayType gat = (GenericArrayType) type; Class rawType = getRawType(gat.getGenericComponentType(), implClass); if (rawType == null) { return null; } return new Class[] {rawType}; } return null; } /** * Shortcut for <code>getComponentTypes(type.getGenericSuperclass())</code>. * * @see #getComponentTypes(java.lang.reflect.Type) */ public static Class[] getGenericSupertypes(Class type) { return getComponentTypes(type.getGenericSuperclass()); } /** * Shortcut for <code>getComponentType(type.getGenericSuperclass())</code>. * * @see #getComponentType(java.lang.reflect.Type, int) */ public static Class getGenericSupertype(Class type, int index) { return getComponentType(type.getGenericSuperclass(), index); } /** * Returns raw class for given <code>type</code>. Use this method with both * regular and generic types. * * @param type the type to convert * @return the closest class representing the given <code>type</code> * @see #getRawType(java.lang.reflect.Type, Class) */ public static Class getRawType(Type type) { return getRawType(type, null); } /** * Returns raw class for given <code>type</code> when implementation class is known * and it makes difference. * @see #resolveVariable(java.lang.reflect.TypeVariable, Class) */ public static Class<?> getRawType(Type type, Class implClass) { if (type instanceof Class) { return (Class) type; } if (type instanceof ParameterizedType) { ParameterizedType pType = (ParameterizedType) type; return getRawType(pType.getRawType(), implClass); } if (type instanceof WildcardType) { WildcardType wType = (WildcardType) type; Type[] lowerTypes = wType.getLowerBounds(); if (lowerTypes.length > 0) { return getRawType(lowerTypes[0], implClass); } Type[] upperTypes = wType.getUpperBounds(); if (upperTypes.length != 0) { return getRawType(upperTypes[0], implClass); } return Object.class; } if (type instanceof GenericArrayType) { Type genericComponentType = ((GenericArrayType) type).getGenericComponentType(); Class<?> rawType = getRawType(genericComponentType, implClass); // this is sort of stupid, but there seems no other way (consider don't creating new instances each time)... return Array.newInstance(rawType, 0).getClass(); } if (type instanceof TypeVariable) { TypeVariable<?> varType = (TypeVariable<?>) type; if (implClass != null) { Type resolvedType = resolveVariable(varType, implClass); if (resolvedType != null) { return getRawType(resolvedType, null); } } Type[] boundsTypes = varType.getBounds(); if (boundsTypes.length == 0) { return Object.class; } return getRawType(boundsTypes[0], implClass); } return null; } /** * Resolves <code>TypeVariable</code> with given implementation class. */ public static Type resolveVariable(TypeVariable variable, final Class implClass) { final Class rawType = getRawType(implClass, null); int index = ArraysUtil.indexOf(rawType.getTypeParameters(), variable); if (index >= 0) { return variable; } final Class[] interfaces = rawType.getInterfaces(); final Type[] genericInterfaces = rawType.getGenericInterfaces(); for (int i = 0; i <= interfaces.length; i++) { Class rawInterface; if (i < interfaces.length) { rawInterface = interfaces[i]; } else { rawInterface = rawType.getSuperclass(); if (rawInterface == null) { continue; } } final Type resolved = resolveVariable(variable, rawInterface); if (resolved instanceof Class || resolved instanceof ParameterizedType) { return resolved; } if (resolved instanceof TypeVariable) { final TypeVariable typeVariable = (TypeVariable) resolved; index = ArraysUtil.indexOf(rawInterface.getTypeParameters(), typeVariable); if (index < 0) { throw new IllegalArgumentException("Invalid type variable:" + typeVariable); } final Type type = i < genericInterfaces.length ? genericInterfaces[i] : rawType.getGenericSuperclass(); if (type instanceof Class) { return Object.class; } if (type instanceof ParameterizedType) { return ((ParameterizedType) type).getActualTypeArguments()[index]; } throw new IllegalArgumentException("Unsupported type: " + type); } } return null; } /** * Converts <code>Type</code> to a <code>String</code>. Supports successor interfaces: * <ul> * <li><code>java.lang.Class</code> - represents usual class</li> * <li><code>java.lang.reflect.ParameterizedType</code> - class with generic parameter (e.g. <code>List</code>)</li> * <li><code>java.lang.reflect.TypeVariable</code> - generic type literal (e.g. <code>List</code>, <code>T</code> - type variable)</li> * <li><code>java.lang.reflect.WildcardType</code> - wildcard type (<code>List<? extends Number></code>, <code>"? extends Number</code> - wildcard type)</li> * <li><code>java.lang.reflect.GenericArrayType</code> - type for generic array (e.g. <code>T[]</code>, <code>T</code> - array type)</li> * </ul> */ public static String typeToString(Type type) { StringBuilder sb = new StringBuilder(); typeToString(sb, type, new HashSet<Type>()); return sb.toString(); } private static void typeToString(StringBuilder sb, Type type, Set<Type> visited) { if (type instanceof ParameterizedType) { ParameterizedType parameterizedType = (ParameterizedType) type; final Class<?> rawType = (Class<?>) parameterizedType.getRawType(); sb.append(rawType.getName()); boolean first = true; for (Type typeArg : parameterizedType.getActualTypeArguments()) { if (first) { first = false; } else { sb.append(", "); } sb.append('<'); typeToString(sb, typeArg, visited); sb.append('>'); } } else if (type instanceof WildcardType) { WildcardType wildcardType = (WildcardType) type; sb.append('?'); // According to JLS(http://java.sun.com/docs/books/jls/third_edition/html/typesValues.html#4.5.1): // - Lower and upper can't coexist: (for instance, this is not allowed: <? extends List<String> & super MyInterface>) // - Multiple bounds are not supported (for instance, this is not allowed: <? extends List<String> & MyInterface>) final Type bound; if (wildcardType.getLowerBounds().length != 0) { sb.append(" super "); bound = wildcardType.getLowerBounds()[0]; } else { sb.append(" extends "); bound = wildcardType.getUpperBounds()[0]; } typeToString(sb, bound, visited); } else if (type instanceof TypeVariable<?>) { TypeVariable<?> typeVariable = (TypeVariable<?>) type; sb.append(typeVariable.getName()); // prevent cycles in case: <T extends List<T>> if (!visited.contains(type)) { visited.add(type); sb.append(" extends "); boolean first = true; for (Type bound : typeVariable.getBounds()) { if (first) { first = false; } else { sb.append(" & "); } typeToString(sb, bound, visited); } visited.remove(type); } } else if (type instanceof GenericArrayType) { GenericArrayType genericArrayType = (GenericArrayType) type; typeToString(genericArrayType.getGenericComponentType()); sb.append(genericArrayType.getGenericComponentType()); sb.append("[]"); } else if (type instanceof Class) { Class<?> typeClass = (Class<?>) type; sb.append(typeClass.getName()); } else { throw new IllegalArgumentException("Unsupported type: " + type); } } // ---------------------------------------------------------------- annotations /** * Reads annotation value. Returns <code>null</code> on error * (e.g. when value name not found). */ public static Object readAnnotationValue(Annotation annotation, String name) { try { Method method = annotation.annotationType().getDeclaredMethod(name); return method.invoke(annotation); } catch (Exception ignore) { return null; } } // ---------------------------------------------------------------- caller private static class ReflectUtilSecurityManager extends SecurityManager { public Class getCallerClass(int callStackDepth) { return getClassContext()[callStackDepth + 1]; } } private static ReflectUtilSecurityManager SECURITY_MANAGER; static { try { SECURITY_MANAGER = new ReflectUtilSecurityManager(); } catch (Exception ex) { SECURITY_MANAGER = null; } } /** * Emulates <code>Reflection.getCallerClass</code> using standard API. * This implementation uses custom <code>SecurityManager</code> * and it is the fastest. Other implementations are: * <ul> * <li><code>new Throwable().getStackTrace()[callStackDepth]</code></li> * <li><code>Thread.currentThread().getStackTrace()[callStackDepth]</code> (the slowest)</li> * </ul> * <p> * In case when usage of <code>SecurityManager</code> is not allowed, * this method fails back to the second implementation. * <p> * Note that original <code>Reflection.getCallerClass</code> is way faster * then any emulation. */ public static Class getCallerClass(int framesToSkip) { if (SECURITY_MANAGER != null) { return SECURITY_MANAGER.getCallerClass(framesToSkip); } StackTraceElement[] stackTraceElements = new Throwable().getStackTrace(); if (framesToSkip >= 2) { framesToSkip += 4; } String className = stackTraceElements[framesToSkip].getClassName(); try { return Thread.currentThread().getContextClassLoader().loadClass(className); } catch (ClassNotFoundException cnfex) { throw new UnsupportedOperationException(className + " not found."); } } /** * Smart variant of {@link #getCallerClass(int)} that skips all relevant Jodd calls. * However, this one does not use the security manager. */ public static Class getCallerClass() { String className = null; StackTraceElement[] stackTraceElements = new Throwable().getStackTrace(); for (StackTraceElement stackTraceElement : stackTraceElements) { className = stackTraceElement.getClassName(); String methodName = stackTraceElement.getMethodName(); if (methodName.equals("loadClass")) { if (className.contains(ClassLoaderStrategy.class.getSimpleName())) { continue; } if (className.equals(ClassLoaderUtil.class.getName())) { continue; } } else if (methodName.equals("getCallerClass")) { continue; } break; } try { return Thread.currentThread().getContextClassLoader().loadClass(className); } catch (ClassNotFoundException cnfex) { throw new UnsupportedOperationException(className + " not found."); } } // ---------------------------------------------------------------- enum /** * Returns <code>enum</code> class or <code>null</code> if class is not an enum. */ public static Class findEnum(Class target) { if (target.isPrimitive()) { return null; } while (target != Object.class) { if (target.isEnum()) { return target; } target = target.getSuperclass(); } return null; } }