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// 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 jodd.net.URLDecoder;

import java.io.File;
import java.io.IOException;
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.net.URL;
import java.security.AccessController;
import java.security.PrivilegedAction;
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;
import java.util.jar.JarFile;

/**
 * Class utilities.
 */
public class ClassUtil {

	/** Empty class array. */
	public static final Class[] EMPTY_CLASS_ARRAY = new Class[0];

	@SuppressWarnings("unchecked")
	public static  Class[] emptyClassArray() {
		return EMPTY_CLASS_ARRAY;
	}

	public static final String METHOD_GET_PREFIX = "get";
	public static final String METHOD_IS_PREFIX = "is";
	public static final String METHOD_SET_PREFIX = "set";

	// ---------------------------------------------------------------- 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(final Class c, final String methodName) {
		return findDeclaredMethod(c, methodName, true);
	}

	/**
	 * @see #findMethod(Class, String)
	 */
	public static Method findDeclaredMethod(final Class c, final String methodName) {
		return findDeclaredMethod(c, methodName, false);
	}

	private static Method findDeclaredMethod(final Class c, final String methodName, final 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  Constructor findConstructor(final Class clazz, final Class... parameterTypes) {
		final Constructor[] constructors = clazz.getConstructors();

		Class[] pts;

		for (Constructor constructor : constructors) {
			pts = constructor.getParameterTypes();

			if (isAllAssignableFrom(pts, parameterTypes)) {
				return (Constructor) constructor;
			}
		}
		return null;
	}

	/**
	 * Returns {@code true} if all types are assignable from the other array of types.
	 */
	public static boolean isAllAssignableFrom(final Class[] typesTarget, final 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(final 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 isAssignableFrom method that
	 * returns false if one of the arguments is null.
	 */
	public static boolean isTypeOf(final Class lookupClass, final Class targetClass) {
		if (targetClass == null || lookupClass == null) {
			return false;
		}
		return targetClass.isAssignableFrom(lookupClass);
	}

	/**
	 * Safe version of isInstance, returns false
	 * if any of the arguments is null.
	 */
	public static boolean isInstanceOf(final Object object, final 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(final Class type) {
		Set bag = new LinkedHashSet<>();
		_resolveAllInterfaces(type, bag);

		return bag.toArray(new Class[0]);
	}

	private static void _resolveAllInterfaces(final Class type, final Set 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. Object
	 * class is not included in the list.
	 */
	public static Class[] resolveAllSuperclasses(Class type) {
		List list = new ArrayList<>();

		while (true) {
			type = type.getSuperclass();

			if ((type == null) || (type == Object.class)) {
				break;
			}
			list.add(type);
		}

		return list.toArray(new Class[0]);
	}

	// ---------------------------------------------------------------- accessible methods


	/**
	 * Returns array of all methods that are accessible from given class.
	 * @see #getAccessibleMethods(Class, Class)
	 */
	public static Method[] getAccessibleMethods(final Class clazz) {
		return getAccessibleMethods(clazz, Object.class);
	}

	/**
	 * Returns array of all methods that are accessible from given class, upto limit
	 * (usually Object.class). Abstract methods are ignored.
	 */
	public static Method[] getAccessibleMethods(Class clazz, final Class limit) {
		Package topPackage = clazz.getPackage();
		List 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(final List allMethods, final Method newMethod) {
		for (Method m : allMethods) {
			if (compareSignatures(m, newMethod)) {
				return;
			}
		}
		allMethods.add(newMethod);
	}

	// ---------------------------------------------------------------- accessible fields


	public static Field[] getAccessibleFields(final Class clazz) {
		return getAccessibleFields(clazz, Object.class);
	}

	public static Field[] getAccessibleFields(Class clazz, final Class limit) {
		Package topPackage = clazz.getPackage();
		List 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(final List allFields, final Field newField) {
		for (Field f : allFields) {
			if (compareSignatures(f, newField)) {
				return;
			}
		}
		allFields.add(newField);
	}


	// ---------------------------------------------------------------- supported methods


	public static Method[] getSupportedMethods(final Class clazz) {
		return getSupportedMethods(clazz, Object.class);
	}

	/**
	 * Returns a Method 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 java.lang.Object. If limit is null then all
	 * methods are returned.
	 */
	public static Method[] getSupportedMethods(final Class clazz, final Class limit) {
		ArrayList 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[0]);
	}


	public static Field[] getSupportedFields(final Class clazz) {
		return getSupportedFields(clazz, Object.class);
	}

	public static Field[] getSupportedFields(final Class clazz, final Class limit) {
		ArrayList 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[0]);
	}


	// ---------------------------------------------------------------- compare

	/**
	 * Compares method declarations: signature and return types.
	 */
	public static boolean compareDeclarations(final Method first, final Method second) {
		if (first.getReturnType() != second.getReturnType()) {
			return false;
		}
		return compareSignatures(first, second);
	}

	/**
	 * Compares method signatures: names and parameters.
	 */
	public static boolean compareSignatures(final Method first, final 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(final Constructor first, final Constructor second) {
		if (!first.getName().equals(second.getName())) {
			return false;
		}
		return compareParameters(first.getParameterTypes(), second.getParameterTypes());
	}

	public static boolean compareSignatures(final Field first, final Field second) {
		return first.getName().equals(second.getName());
	}

	/**
	 * Compares classes, usually method or ctor parameters.
	 */
	public static boolean compareParameters(final Class[] first, final 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(final AccessibleObject accObject) {
		try {
			if (System.getSecurityManager() == null)
				accObject.setAccessible(true);
			else {
				AccessController.doPrivileged((PrivilegedAction) () -> {
					accObject.setAccessible(true);
					return null;
				});
			}
		} catch (SecurityException sex) {
			// ignore
		}
	}

	// ---------------------------------------------------------------- is public

	/**
	 * Returns true if class member is public.
	 */
	public static boolean isPublic(final Member member) {
		return Modifier.isPublic(member.getModifiers());
	}

	/**
	 * Returns true if class member is public and if its declaring class is also public.
	 */
	public static boolean isPublicPublic(final Member member) {
		if (Modifier.isPublic(member.getModifiers())) {
			if (Modifier.isPublic(member.getDeclaringClass().getModifiers())) {
				return true;
			}
		}
		return false;
	}

	/**
	 * Returns true if class is public.
	 */
	public static boolean isPublic(final Class c) {
		return Modifier.isPublic(c.getModifiers());
	}


	// ---------------------------------------------------------------- create

	/**
	 * Creates new instance of given class with given optional arguments.
	 */
	@SuppressWarnings("unchecked")
	public static  T newInstance(final Class clazz, final Object... params) throws InstantiationException, IllegalAccessException, InvocationTargetException, NoSuchMethodException {
		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 if blocks
	 * is faster then using a HashMap.
	 */
	@SuppressWarnings("unchecked")
	public static  T newInstance(final Class type) throws IllegalAccessException, InstantiationException, NoSuchMethodException, InvocationTargetException {
		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.getName().startsWith("java.")) {

			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);
		}

		Constructor declaredConstructor = type.getDeclaredConstructor();

		forceAccess(declaredConstructor);

		return declaredConstructor.newInstance();
	}


	// ---------------------------------------------------------------- misc

	/**
	 * Returns true if the first member is accessible from second one.
	 */
	public static boolean isAssignableFrom(final Member member1, final Member member2) {
		return member1.getDeclaringClass().isAssignableFrom(member2.getDeclaringClass());
	}

	/**
	 * Returns all superclasses.
	 */
	public static Class[] getSuperclasses(final 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 true if method is user defined and not defined in Object class.
	 */
	public static boolean isUserDefinedMethod(final Method method) {
		return method.getDeclaringClass() != Object.class;
	}

	/**
	 * Returns true if method defined in Object class.
	 */
	public static boolean isObjectMethod(final Method method) {
		return method.getDeclaringClass() == Object.class;
	}


	/**
	 * Returns true if method is a bean property.
	 */
	public static boolean isBeanProperty(final 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 true if method is bean getter.
	 */
	public static boolean isBeanPropertyGetter(final Method method) {
		return getBeanPropertyGetterPrefixLength(method) != 0;
	}

	private static int getBeanPropertyGetterPrefixLength(final 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 null if method is not a real getter.
	 */
	public static String getBeanPropertyGetterName(final Method method) {
		int prefixLength = getBeanPropertyGetterPrefixLength(method);
		if (prefixLength == 0) {
			return null;
		}
		String methodName = method.getName().substring(prefixLength);
		return StringUtil.decapitalize(methodName);
	}

	/**
	 * Returns true if method is bean setter.
	 */
	public static boolean isBeanPropertySetter(final Method method) {
		return getBeanPropertySetterPrefixLength(method) != 0;
	}

	private static int getBeanPropertySetterPrefixLength(final 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 null if method is not a real setter.
	 */
	public static String getBeanPropertySetterName(final 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 null if component type
	 * does not exist or if index is out of bounds.
	 *
	 * @see #getComponentTypes(java.lang.reflect.Type)
	 */
	public static Class getComponentType(final Type type, final 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 null if component type
	 * does not exist or if index is out of bounds.
	 * 

* * @see #getComponentTypes(java.lang.reflect.Type, Class) */ public static Class getComponentType(final Type type, final 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(final 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: *

    *
  • MyClass[]
  • *
  • List<MyClass>
  • *
  • Foo<? extends MyClass>
  • *
  • Bar<? super MyClass>
  • *
  • <T extends MyClass> T[]
  • *
*/ public static Class[] getComponentTypes(final Type type, final 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 getComponentTypes(type.getGenericSuperclass()). * * @see #getComponentTypes(java.lang.reflect.Type) */ public static Class[] getGenericSupertypes(final Class type) { return getComponentTypes(type.getGenericSuperclass()); } /** * Shortcut for getComponentType(type.getGenericSuperclass()). * * @see #getComponentType(java.lang.reflect.Type, int) */ public static Class getGenericSupertype(final Class type, final int index) { return getComponentType(type.getGenericSuperclass(), index); } /** * Returns raw class for given type. Use this method with both * regular and generic types. * * @param type the type to convert * @return the closest class representing the given type * @see #getRawType(java.lang.reflect.Type, Class) */ public static Class getRawType(final Type type) { return getRawType(type, null); } /** * Returns raw class for given type when implementation class is known * and it makes difference. * @see #resolveVariable(java.lang.reflect.TypeVariable, Class) */ public static Class getRawType(final Type type, final 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 TypeVariable with given implementation class. */ public static Type resolveVariable(final 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 Type to a String. Supports successor interfaces: *
    *
  • java.lang.Class - represents usual class
  • *
  • java.lang.reflect.ParameterizedType - class with generic parameter (e.g. List)
  • *
  • java.lang.reflect.TypeVariable - generic type literal (e.g. List, T - type variable)
  • *
  • java.lang.reflect.WildcardType - wildcard type (List<? extends Number>, "? extends Number - wildcard type)
  • *
  • java.lang.reflect.GenericArrayType - type for generic array (e.g. T[], T - array type)
  • *
*/ public static String typeToString(final Type type) { StringBuilder sb = new StringBuilder(); typeToString(sb, type, new HashSet()); return sb.toString(); } private static void typeToString(final StringBuilder sb, final Type type, final Set 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: & super MyInterface>) // - Multiple bounds are not supported (for instance, this is not allowed: & 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: > 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 null on error * (e.g. when value name not found). */ public static Object readAnnotationValue(final Annotation annotation, final 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(final int callStackDepth) { return getClassContext()[callStackDepth + 1]; } } private static ReflectUtilSecurityManager SECURITY_MANAGER; static { try { SECURITY_MANAGER = new ReflectUtilSecurityManager(); } catch (Exception ex) { SECURITY_MANAGER = null; } } /** * Emulates Reflection.getCallerClass using standard API. * This implementation uses custom SecurityManager * and it is the fastest. Other implementations are: *
    *
  • new Throwable().getStackTrace()[callStackDepth]
  • *
  • Thread.currentThread().getStackTrace()[callStackDepth] (the slowest)
  • *
*

* In case when usage of SecurityManager is not allowed, * this method fails back to the second implementation. *

* Note that original Reflection.getCallerClass 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 enum class or null 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; } // ---------------------------------------------------------------- misc /** * Returns the class of the immediate subclass of the given parent class for * the given object instance; or null if such immediate subclass cannot be * uniquely identified for the given object instance. */ public static Class childClassOf(final Class parentClass, final Object instance) { if (instance == null || instance == Object.class) { return null; } if (parentClass != null) { if (parentClass.isInterface()) { return null; } } Class childClass = instance.getClass(); while (true) { Class parent = childClass.getSuperclass(); if (parent == parentClass) { return childClass; } if (parent == null) { return null; } childClass = parent; } } /** * Returns the jar file from which the given class is loaded; or null * if no such jar file can be located. */ public static JarFile jarFileOf(final Class klass) { URL url = klass.getResource( "/" + klass.getName().replace('.', '/') + ".class"); if (url == null) { return null; } String s = url.getFile(); int beginIndex = s.indexOf("file:") + "file:".length(); int endIndex = s.indexOf(".jar!"); if (endIndex == -1) { return null; } endIndex += ".jar".length(); String f = s.substring(beginIndex, endIndex); // decode URL string - it may contain encoded chars (e.g. whitespaces) which are not supported for file-instances f = URLDecoder.decode(f, "UTF-8"); File file = new File(f); try { return file.exists() ? new JarFile(file) : null; } catch (IOException e) { throw new IllegalStateException(e); } } // ---------------------------------------------------------------- class names /** * Resolves class file name from class name by replacing dot's with '/' separator * and adding class extension at the end. If array, component type is returned. */ public static String convertClassNameToFileName(Class clazz) { if (clazz.isArray()) { clazz = clazz.getComponentType(); } return convertClassNameToFileName(clazz.getName()); } /** * Resolves class file name from class name by replacing dot's with '/' separator. */ public static String convertClassNameToFileName(final String className) { return className.replace('.', '/') + ".class"; } /** * Returns short class name: packages are replaces with single letter. */ public static String getShortClassName(final Class clazz) { return getShortClassName(clazz, 1); } public static String getShortClassName(final Class clazz, final int shortUpTo) { final String[] chunks = StringUtil.splitc(clazz.getName(), '.'); final StringBand stringBand = new StringBand(chunks.length); int ndx = chunks.length - shortUpTo; if (ndx < 0) { ndx = 0; } for (int i = 0; i < ndx; i++) { if (i > 0) { stringBand.append('.'); } stringBand.append(chunks[i].charAt(0)); } for (int i = ndx; i < chunks.length; i++) { if (i > 0) { stringBand.append('.'); } stringBand.append(chunks[i]); } return stringBand.toString(); } // ---------------------------------------------------------------- kotlin /** * Returns {@code true} if type is a Kotlin class. */ public static boolean isKotlinClass(final Class type) { final Annotation[] annotations = type.getAnnotations(); for (Annotation annotation : annotations) { if (annotation.annotationType().getName().equals("kotlin.Metadata")) { return true; } } return false; } }





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