Dépôt officiel du code source de l'ERP OpenConcerto

/*

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS HEADER.

 *

 * Copyright 2011-2019 OpenConcerto, by ILM Informatique. All rights reserved.

 *

 * The contents of this file are subject to the terms of the GNU General Public License Version 3

 * only ("GPL"). You may not use this file except in compliance with the License. You can obtain a

 * copy of the License at http://www.gnu.org/licenses/gpl-3.0.html See the License for the specific

 * language governing permissions and limitations under the License.

 *

 * When distributing the software, include this License Header Notice in each file.

 */

 package org.openconcerto.utils;

import java.util.ArrayList;

import java.util.Arrays;

import java.util.Collections;

import java.util.List;

import java.util.function.Function;

import java.util.regex.Pattern;

public class SystemUtils {

    /**

     * Wrap a system property and view it as a list.

     *

     * @author Sylvain CUAZ

     */

    public static final class PropertyList {

        private final String name;

        private final Pattern p;

        /**

         * Create a new instance.

         *

         * @param name name of the property, e.g. "java.protocol.handler.pkgs".

         * @param sep the separator used, e.g. "|".

         */

        public PropertyList(final String name, final String sep) {

            this.name = name;

            this.p = Pattern.compile(sep, Pattern.LITERAL);

        }

        public final String getName() {

            return this.name;

        }

        private final String getSeparator() {

            return this.p.pattern();

        }

        public final String getValue() {

            return System.getProperty(this.name);

        }

        public final List<String> getValues() {

            return getList(getValue());

        }

        private final List<String> getList(final String current) {

            if (current == null)

                return null;

            else if (current.length() == 0)

                return Collections.emptyList();

            else {

                return Arrays.asList(this.p.split(current));

            }

        }

        /**

         * Adds a value to the system property list if not already present.

         *

         * @param value the value to add, e.g. "sun.net.www.protocol".

         * @return <code>true</code> if the property was modified.

         */

        public final boolean add(final String value) {

            return this.add(value, true);

        }

        public final boolean add(final String value, boolean append) {

            if (value == null)

                throw new NullPointerException("Null value");

            final String current = getValue();

            final List<String> l = getList(current);

            final String newVal;

            if (l == null || l.size() == 0)

                newVal = value;

            else if (l.contains(value))

                newVal = null;

            else if (append)

                newVal = current + this.getSeparator() + value;

            else

                newVal = value + this.getSeparator() + current;

            if (newVal != null) {

                System.setProperty(this.name, newVal);

                return true;

            } else

                return false;

        }

        public final boolean remove(final String value) {

            return this.remove(value, true);

        }

        public final boolean remove(final String value, final boolean unsetIfEmpty) {

            if (value == null)

                throw new NullPointerException("Null value");

            final List<String> l = getValues();

            if (l == null || l.size() == 0 || !l.contains(value))

                return false;

            final List<String> newList = new ArrayList<>(l.size() - 1);

            for (final String item : l) {

                if (!item.equals(value))

                    newList.add(item);

            }

            if (unsetIfEmpty && newList.isEmpty())

                System.clearProperty(this.name);

            else

                System.setProperty(this.name, CollectionUtils.join(newList, this.getSeparator()));

            return true;

        }

    }

    static public final <T extends Enum<T>> T getEnumFromProperty(final String propName, final Class<T> clazz, final T def) {

        final String prop = System.getProperty(propName);

        if (prop == null)

            return def;

        return Enum.valueOf(clazz, propName);

    }

    static public final <T> T getProperty(final String propName, final Function<String, T> func, final T def) {

        final String prop = System.getProperty(propName);

        if (prop == null)

            return def;

        return func.apply(prop);

    }

}