001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.vfs2.util;
018
019import java.text.MessageFormat;
020import java.util.MissingResourceException;
021import java.util.ResourceBundle;
022import java.util.concurrent.ConcurrentHashMap;
023import java.util.concurrent.ConcurrentMap;
024
025import org.apache.commons.lang3.ArrayUtils;
026
027/**
028 * Formats messages.
029 */
030public final class Messages {
031
032    /**
033     * Map from message code to MessageFormat object for the message.
034     */
035    private static final ConcurrentMap<String, MessageFormat> MESSAGE_MAP = new ConcurrentHashMap<>();
036    private static final ResourceBundle RESOURCES = new CombinedResources("org.apache.commons.vfs2.Resources");
037
038    /**
039     * Locates a message by its code.
040     */
041    private static MessageFormat findMessage(final String code) throws MissingResourceException {
042        // Check if the message is cached
043        return MESSAGE_MAP.computeIfAbsent(code, k -> new MessageFormat(RESOURCES.getString(k)));
044    }
045
046    /**
047     * Formats a message.
048     *
049     * @param code The message code.
050     * @return The formatted message.
051     */
052    public static String getString(final String code) {
053        return getString(code, ArrayUtils.EMPTY_OBJECT_ARRAY);
054    }
055
056    /**
057     * Formats a message.
058     *
059     * @param code The message code.
060     * @param param The message parameter.
061     * @return The formatted message.
062     * @deprecated Will be removed in 3.0 in favor of {@link #getString(String, Object[])} When removed, calls to this
063     *             method will automatically recompile to {@link #getString(String, Object[])}
064     */
065    @Deprecated
066    public static String getString(final String code, final Object param) {
067        return getString(code, new Object[] {param});
068    }
069
070    /**
071     * Formats a message.
072     *
073     * @param code The message code.
074     * @param params The message parameters.
075     * @return The formatted message.
076     */
077    public static String getString(final String code, final Object... params) {
078        try {
079            if (code == null) {
080                return null;
081            }
082            return findMessage(code).format(params);
083        } catch (final MissingResourceException mre) {
084            return "Unknown message with code \"" + code + "\".";
085        }
086    }
087
088    private Messages() {
089        // no instances.
090    }
091}