/*

 * Copyright 1999-2008 Sun Microsystems, Inc.  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.  Sun designates this

 * particular file as subject to the "Classpath" exception as provided

 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

package com.sun.tools.doclets.internal.toolkit.util;

import com.sun.javadoc.*;

import com.sun.tools.doclets.internal.toolkit.Configuration;

import java.util.*;

/**

 * For a given class method, build an array of interface methods which it

 * implements.

 *

 * This code is not part of an API.

 * It is implementation that is subject to change.

 * Do not use it as an API

 *

 * @author Atul M Dambalkar

 */

public class ImplementedMethods {

    private Map<MethodDoc,Type> interfaces = new HashMap<MethodDoc,Type>();

    private List<MethodDoc> methlist = new ArrayList<MethodDoc>();

    private Configuration configuration;

    private final ClassDoc classdoc;

    private final MethodDoc method;

    public ImplementedMethods(MethodDoc method, Configuration configuration) {

        this.method = method;

        this.configuration = configuration;

        classdoc = method.containingClass();

    }

    /**

     * Return the array of interface methods which the method passed in the

     * constructor is implementing. The search/build order is as follows:

     * <pre>

     * 1. Search in all the immediate interfaces which this method's class is

     *    implementing. Do it recursively for the superinterfaces as well.

     * 2. Traverse all the superclasses and search recursively in the

     *    interfaces which those superclasses implement.

     *</pre>

     *

     * @return MethodDoc[] Array of implemented methods.

     */

    public MethodDoc[] build(boolean sort) {

        buildImplementedMethodList(sort);

        return methlist.toArray(new MethodDoc[methlist.size()]);

    }

    public MethodDoc[] build() {

        return build(true);

    }

    public Type getMethodHolder(MethodDoc methodDoc) {

        return interfaces.get(methodDoc);

    }

    /**

     * Search for the method in the array of interfaces. If found check if it is

     * overridden by any other subinterface method which this class

     * implements. If it is not overidden, add it in the method list.

     * Do this recursively for all the extended interfaces for each interface

     * from the array passed.

     */

    private void buildImplementedMethodList(boolean sort) {

            MethodDoc found = Util.findMethod(interfaceType.asClassDoc(), method);

            if (found != null) {

                removeOverriddenMethod(found);

                if (!overridingMethodFound(found)) {

                    methlist.add(found);

                    interfaces.put(found, interfaceType);

                }

            }

        }

    }

    /**

     * Search in the method list and check if it contains a method which

     * is overridden by the method as parameter.  If found, remove the

     * overridden method from the method list.

     *

     * @param method Is this method overriding a method in the method list.

     */

    private void removeOverriddenMethod(MethodDoc method) {

        ClassDoc overriddenClass = method.overriddenClass();

        if (overriddenClass != null) {

            for (int i = 0; i < methlist.size(); i++) {

                ClassDoc cd = methlist.get(i).containingClass();

                if (cd == overriddenClass || overriddenClass.subclassOf(cd)) {

                    methlist.remove(i);  // remove overridden method

                    return;

                }

            }

        }

    }

    /**

     * Search in the already found methods' list and check if it contains

     * a method which is overriding the method parameter or is the method

     * parameter itself.

     *

     * @param method MethodDoc Method to be searched in the Method List for

     * an overriding method.

     */

    private boolean overridingMethodFound(MethodDoc method) {

        ClassDoc containingClass = method.containingClass();

        for (int i = 0; i < methlist.size(); i++) {

            MethodDoc listmethod = methlist.get(i);

            if (containingClass == listmethod.containingClass()) {

                // it's the same method.

                return true;

            }

            ClassDoc cd = listmethod.overriddenClass();

            if (cd == null) {

                continue;

            }

            if (cd == containingClass || cd.subclassOf(containingClass)) {

                return true;

            }

        }

        return false;

    }

}