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 * 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

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package jdk.javadoc.internal.doclets.toolkit.util;

import java.util.*;

import javax.lang.model.element.ModuleElement;

import javax.lang.model.element.PackageElement;

import jdk.javadoc.internal.doclets.toolkit.Messages;

/**

 * Process and manage grouping of elements, as specified by "-group" option on

 * the command line.

 * <p>

 * For example, if user has used -group option as

 * -group "Core Packages" "java.*" -group "CORBA Packages" "org.omg.*", then

 * the packages specified on the command line will be grouped according to their

 * names starting with either "java." or "org.omg.". All the other packages

 * which do not fall in the user given groups, are grouped in default group,

 * named as either "Other Packages" or "Packages" depending upon if "-group"

 * option used or not at all used respectively.

 * </p>

 * <p>

 * Also the packages are grouped according to the longest possible match of

 * their names with the grouping information provided. For example, if there

 * are two groups, like -group "Lang" "java.lang" and -group "Core" "java.*",

 * will put the package java.lang in the group "Lang" and not in group "Core".

 * </p>

 *

 *  <p><b>This is NOT part of any supported API.

 *  If you write code that depends on this, you do so at your own risk.

 *  This code and its internal interfaces are subject to change or

 *  deletion without notice.</b>

 *

 * @author Atul M Dambalkar

 */

public class Group {

    /**

     * Map of regular expressions with the corresponding group name.

     */

    private Map<String,String> regExpGroupMap = new HashMap<>();

    /**

     * List of regular expressions sorted according to the length. Regular

     * expression with longest length will be first in the sorted order.

     */

    private List<String> sortedRegExpList = new ArrayList<>();

    /**

     * List of group names in the same order as given on the command line.

     */

    private List<String> groupList = new ArrayList<>();

    /**

     * Map of non-regular expressions(possible package or module names) with the

     * corresponding group name.

     */

    private Map<String,String> elementNameGroupMap = new HashMap<>();

    /**

     * The global configuration information for this run.

     */

    private Messages messages;

    /**

     * Since we need to sort the keys in the reverse order(longest key first),

     * the compare method in the implementing class is doing the reverse

     * comparison.

     */

    private static class MapKeyComparator implements Comparator<String> {

        public int compare(String key1, String key2) {

            return key2.length() - key1.length();

        }

    }

        this.configuration = configuration;

        messages = configuration.getMessages();

    }

    /**

     * Depending upon the format of the module name provided in the "-group"

     * option, generate two separate maps. There will be a map for mapping

     * regular expression(only meta character allowed is '*' and that is at the

     * end of the regular expression) on to the group name. And another map

     * for mapping (possible) module names(if the name format doesn't contain

     * meta character '*', then it is assumed to be a module name) on to the

     * group name. This will also sort all the regular expressions found in the

     * reverse order of their lengths, i.e. longest regular expression will be

     * first in the sorted list.

     *

     * @param groupname       The name of the group from -group option.

     * @param moduleNameFormList List of the module name formats.

     */

    public boolean checkModuleGroups(String groupname, String moduleNameFormList) {

        String[] mdlPatterns = moduleNameFormList.split(":");

        if (groupList.contains(groupname)) {

            initMessages();

            messages.warning("doclet.Groupname_already_used", groupname);

            return false;

        }

        groupList.add(groupname);

        for (String mdlPattern : mdlPatterns) {

            if (mdlPattern.length() == 0) {

                initMessages();

                messages.warning("doclet.Error_in_grouplist", groupname, moduleNameFormList);

                return false;

            }

            if (mdlPattern.endsWith("*")) {

                mdlPattern = mdlPattern.substring(0, mdlPattern.length() - 1);

                if (foundGroupFormat(regExpGroupMap, mdlPattern)) {

                    return false;

                }

                regExpGroupMap.put(mdlPattern, groupname);

                sortedRegExpList.add(mdlPattern);

            } else {

                if (foundGroupFormat(elementNameGroupMap, mdlPattern)) {

                    return false;

                }

                elementNameGroupMap.put(mdlPattern, groupname);

            }

        }

        Collections.sort(sortedRegExpList, new MapKeyComparator());

        return true;

    }

    /**

     * Depending upon the format of the package name provided in the "-group"

     * option, generate two separate maps. There will be a map for mapping

     * regular expression(only meta character allowed is '*' and that is at the

     * end of the regular expression) on to the group name. And another map

     * for mapping (possible) package names(if the name format doesn't contain

     * meta character '*', then it is assumed to be a package name) on to the

     * group name. This will also sort all the regular expressions found in the

     * reverse order of their lengths, i.e. longest regular expression will be

     * first in the sorted list.

     *

     * @param groupname       The name of the group from -group option.

     * @param pkgNameFormList List of the package name formats.

     */

    public boolean checkPackageGroups(String groupname, String pkgNameFormList) {

        String[] pkgPatterns = pkgNameFormList.split(":");

        if (groupList.contains(groupname)) {

            initMessages();

            messages.warning("doclet.Groupname_already_used", groupname);

            return false;

        }

        groupList.add(groupname);

        for (String pkgPattern : pkgPatterns) {

            if (pkgPattern.length() == 0) {

                initMessages();

                messages.warning("doclet.Error_in_grouplist", groupname, pkgNameFormList);

                return false;

            }

            if (pkgPattern.endsWith("*")) {

                pkgPattern = pkgPattern.substring(0, pkgPattern.length() - 1);

                if (foundGroupFormat(regExpGroupMap, pkgPattern)) {

                    return false;

                }

                regExpGroupMap.put(pkgPattern, groupname);

                sortedRegExpList.add(pkgPattern);

            } else {

                if (foundGroupFormat(elementNameGroupMap, pkgPattern)) {

                    return false;

                }

                elementNameGroupMap.put(pkgPattern, groupname);

            }

        }

        Collections.sort(sortedRegExpList, new MapKeyComparator());

        return true;

    }

    // Lazy init of the messages for now, because Group is created

    private void initMessages() {

        if (messages == null) {

            messages = configuration.getMessages();

        }

    }

    /**

     * Search if the given map has the given element format.

     *

     * @param map Map to be searched.

     * @param elementFormat The format to search.

     *

     * @return true if element name format found in the map, else false.

     */

    boolean foundGroupFormat(Map<String,?> map, String elementFormat) {

        if (map.containsKey(elementFormat)) {

            initMessages();

            messages.error("doclet.Same_element_name_used", elementFormat);

            return true;

        }

        return false;

    }

    /**

     * Group the modules according the grouping information provided on the

     * command line. Given a list of modules, search each module name in

     * regular expression map as well as module name map to get the

     * corresponding group name. Create another map with mapping of group name

     * to the module list, which will fall under the specified group. If any

     * module doesn't belong to any specified group on the command line, then

     * a new group named "Other Modules" will be created for it. If there are

     * no groups found, in other words if "-group" option is not at all used,

     * then all the modules will be grouped under group "Modules".

     *

     * @param modules Specified modules.

     * @return map of group names and set of module elements.

     */

    public Map<String, SortedSet<ModuleElement>> groupModules(Set<ModuleElement> modules) {

        Map<String, SortedSet<ModuleElement>> groupModuleMap = new HashMap<>();

        String defaultGroupName =

            (elementNameGroupMap.isEmpty() && regExpGroupMap.isEmpty())?

                configuration.getResources().getText("doclet.Modules") :

                configuration.getResources().getText("doclet.Other_Modules");

        // if the user has not used the default group name, add it

        if (!groupList.contains(defaultGroupName)) {

            groupList.add(defaultGroupName);

        }

        for (ModuleElement mdl : modules) {

            String moduleName = mdl.isUnnamed() ? null : mdl.getQualifiedName().toString();

            String groupName = mdl.isUnnamed() ? null : elementNameGroupMap.get(moduleName);

            // if this module is not explicitly assigned to a group,

            // try matching it to group specified by regular expression

            if (groupName == null) {

                groupName = regExpGroupName(moduleName);

            }

            // if it is in neither group map, put it in the default

            // group

            if (groupName == null) {

                groupName = defaultGroupName;

            }

            getModuleList(groupModuleMap, groupName).add(mdl);

        }

        return groupModuleMap;

    }

    /**

     * Group the packages according the grouping information provided on the

     * command line. Given a list of packages, search each package name in

     * regular expression map as well as package name map to get the

     * corresponding group name. Create another map with mapping of group name

     * to the package list, which will fall under the specified group. If any

     * package doesn't belong to any specified group on the command line, then

     * a new group named "Other Packages" will be created for it. If there are

     * no groups found, in other words if "-group" option is not at all used,

     * then all the packages will be grouped under group "Packages".

     *

     * @param packages Packages specified on the command line.

     * @return map of group names and set of package elements

     */

    public Map<String, SortedSet<PackageElement>> groupPackages(Set<PackageElement> packages) {

        Map<String, SortedSet<PackageElement>> groupPackageMap = new HashMap<>();

        String defaultGroupName =

            (elementNameGroupMap.isEmpty() && regExpGroupMap.isEmpty())?

                configuration.getResources().getText("doclet.Packages") :

                configuration.getResources().getText("doclet.Other_Packages");

        // if the user has not used the default group name, add it

        if (!groupList.contains(defaultGroupName)) {

            groupList.add(defaultGroupName);

        }

        for (PackageElement pkg : packages) {

            String pkgName = pkg.isUnnamed() ? null : configuration.utils.getPackageName(pkg);

            String groupName = pkg.isUnnamed() ? null : elementNameGroupMap.get(pkgName);

            // if this package is not explicitly assigned to a group,

            // try matching it to group specified by regular expression

            if (groupName == null) {

                groupName = regExpGroupName(pkgName);

            }

            // if it is in neither group map, put it in the default

            // group

            if (groupName == null) {

                groupName = defaultGroupName;

            }

            getPkgList(groupPackageMap, groupName).add(pkg);

        }

        return groupPackageMap;

    }

    /**

     * Search for element name in the sorted regular expression

     * list, if found return the group name.  If not, return null.

     *

     * @param elementName Name of element to be found in the regular

     * expression list.

     */

    String regExpGroupName(String elementName) {

        for (String regexp : sortedRegExpList) {

            if (elementName.startsWith(regexp)) {

                return regExpGroupMap.get(regexp);

            }

        }

        return null;

    }

    /**

     * For the given group name, return the package list, on which it is mapped.

     * Create a new list, if not found.

     *

     * @param map Map to be searched for group name.

     * @param groupname Group name to search.

     */

    SortedSet<PackageElement> getPkgList(Map<String, SortedSet<PackageElement>> map,

            String groupname) {

        return map.computeIfAbsent(groupname, g -> new TreeSet<>(configuration.utils.makePackageComparator()));

    }

    /**

     * For the given group name, return the module list, on which it is mapped.

     * Create a new list, if not found.

     *

     * @param map Map to be searched for group name.

     * @param groupname Group name to search.

     */

    SortedSet<ModuleElement> getModuleList(Map<String, SortedSet<ModuleElement>> map,

            String groupname) {

        return map.computeIfAbsent(groupname, g -> new TreeSet<>(configuration.utils.makeModuleComparator()));

    }

    /**

     * Return the list of groups, in the same order as specified

     * on the command line.

     */

    public List<String> getGroupList() {

        return groupList;

    }

}