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	/*
	* Copyright (c) 2008, 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
	* This code is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 only, as
	* published by the Free Software Foundation. Oracle designates this
	* particular file as subject to the "Classpath" exception as provided
	* by Oracle in the LICENSE file that accompanied this code.
	*
	* This code is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	* version 2 for more details (a copy is included in the LICENSE file that
	* accompanied this code).
	*
	* You should have received a copy of the GNU General Public License version
	* 2 along with this work; if not, write to the Free Software Foundation,
	* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
	*
	* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
	* or visit www.oracle.com if you need additional information or have any
	* questions.
	*/
	package com.sun.beans.finder;

	import com.sun.beans.TypeResolver;
	import com.sun.beans.util.Cache;

	import java.lang.reflect.Method;
	import java.lang.reflect.Modifier;
	import java.lang.reflect.ParameterizedType;
	import java.lang.reflect.Type;
	import java.util.Arrays;

	import static com.sun.beans.util.Cache.Kind.SOFT;
	import static sun.reflect.misc.ReflectUtil.isPackageAccessible;

	/**
	* This utility class provides {@code static} methods
	* to find a public method with specified name and parameter types
	* in specified class.
	*
	* @since 1.7
	*
	* @author Sergey A. Malenkov
	*/
	public final class MethodFinder extends AbstractFinder<Method> {
	private static final Cache<Signature, Method> CACHE = new Cache<Signature, Method>(SOFT, SOFT) {
	@Override
	public Method create(Signature signature) {
	try {
	MethodFinder finder = new MethodFinder(signature.getName(), signature.getArgs());
	return findAccessibleMethod(finder.find(signature.getType().getMethods()));
	}
	catch (Exception exception) {
	throw new SignatureException(exception);
	}
	}
	};

	/**
	* Finds public method (static or non-static)
	* that is accessible from public class.
	*
	* @param type the class that can have method
	* @param name the name of method to find
	* @param args parameter types that is used to find method
	* @return object that represents found method
	* @throws NoSuchMethodException if method could not be found
	* or some methods are found
	*/
	public static Method findMethod(Class<?> type, String name, Class<?>...args) throws NoSuchMethodException {
	if (name == null) {
	throw new IllegalArgumentException("Method name is not set");
	}
	PrimitiveWrapperMap.replacePrimitivesWithWrappers(args);
	Signature signature = new Signature(type, name, args);

	try {
	Method method = CACHE.get(signature);
	return (method == null) \|\| isPackageAccessible(method.getDeclaringClass()) ? method : CACHE.create(signature);
	}
	catch (SignatureException exception) {
	throw exception.toNoSuchMethodException("Method '" + name + "' is not found");
	}
	}

	/**
	* Finds public non-static method
	* that is accessible from public class.
	*
	* @param type the class that can have method
	* @param name the name of method to find
	* @param args parameter types that is used to find method
	* @return object that represents found method
	* @throws NoSuchMethodException if method could not be found
	* or some methods are found
	*/
	public static Method findInstanceMethod(Class<?> type, String name, Class<?>... args) throws NoSuchMethodException {
	Method method = findMethod(type, name, args);
	if (Modifier.isStatic(method.getModifiers())) {
	throw new NoSuchMethodException("Method '" + name + "' is static");
	}
	return method;
	}

	/**
	* Finds public static method
	* that is accessible from public class.
	*
	* @param type the class that can have method
	* @param name the name of method to find
	* @param args parameter types that is used to find method
	* @return object that represents found method
	* @throws NoSuchMethodException if method could not be found
	* or some methods are found
	*/
	public static Method findStaticMethod(Class<?> type, String name, Class<?>...args) throws NoSuchMethodException {
	Method method = findMethod(type, name, args);
	if (!Modifier.isStatic(method.getModifiers())) {
	throw new NoSuchMethodException("Method '" + name + "' is not static");
	}
	return method;
	}

	/**
	* Finds method that is accessible from public class or interface through class hierarchy.
	*
	* @param method object that represents found method
	* @return object that represents accessible method
	* @throws NoSuchMethodException if method is not accessible or is not found
	* in specified superclass or interface
	*/
	public static Method findAccessibleMethod(Method method) throws NoSuchMethodException {
	Class<?> type = method.getDeclaringClass();
	if (Modifier.isPublic(type.getModifiers()) && isPackageAccessible(type)) {
	return method;
	}
	if (Modifier.isStatic(method.getModifiers())) {
	throw new NoSuchMethodException("Method '" + method.getName() + "' is not accessible");
	}
	for (Type generic : type.getGenericInterfaces()) {
	try {
	return findAccessibleMethod(method, generic);
	}
	catch (NoSuchMethodException exception) {
	// try to find in superclass or another interface
	}
	}
	return findAccessibleMethod(method, type.getGenericSuperclass());
	}

	/**
	* Finds method that accessible from specified class.
	*
	* @param method object that represents found method
	* @param generic generic type that is used to find accessible method
	* @return object that represents accessible method
	* @throws NoSuchMethodException if method is not accessible or is not found
	* in specified superclass or interface
	*/
	private static Method findAccessibleMethod(Method method, Type generic) throws NoSuchMethodException {
	String name = method.getName();
	Class<?>[] params = method.getParameterTypes();
	if (generic instanceof Class) {
	Class<?> type = (Class<?>) generic;
	return findAccessibleMethod(type.getMethod(name, params));
	}
	if (generic instanceof ParameterizedType) {
	ParameterizedType pt = (ParameterizedType) generic;
	Class<?> type = (Class<?>) pt.getRawType();
	for (Method m : type.getMethods()) {
	if (m.getName().equals(name)) {
	Class<?>[] pts = m.getParameterTypes();
	if (pts.length == params.length) {
	if (Arrays.equals(params, pts)) {
	return findAccessibleMethod(m);
	}
	Type[] gpts = m.getGenericParameterTypes();
	if (params.length == gpts.length) {
	if (Arrays.equals(params, TypeResolver.erase(TypeResolver.resolve(pt, gpts)))) {
	return findAccessibleMethod(m);
	}
	}
	}
	}
	}
	}
	throw new NoSuchMethodException("Method '" + name + "' is not accessible");
	}


	private final String name;

	/**
	* Creates method finder with specified array of parameter types.
	*
	* @param name the name of method to find
	* @param args the array of parameter types
	*/
	private MethodFinder(String name, Class<?>[] args) {
	super(args);
	this.name = name;
	}

	/**
	* Checks validness of the method.
	* The valid method should be public and
	* should have the specified name.
	*
	* @param method the object that represents method
	* @return {@code true} if the method is valid,
	* {@code false} otherwise
	*/
	@Override
	protected boolean isValid(Method method) {
	return super.isValid(method) && method.getName().equals(this.name);
	}
	}

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