001 /*
002 * Created on Jan 25, 2008
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with
005 * the License. You may obtain a copy of the License at
006 *
007 * http://www.apache.org/licenses/LICENSE-2.0
008 *
009 * Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on
010 * an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the
011 * specific language governing permissions and limitations under the License.
012 *
013 * Copyright @2008-2011 the original author or authors.
014 */
015 package org.fest.util;
016
017 import static org.fest.util.ToString.toStringOf;
018
019 import java.util.*;
020 import java.util.Map.Entry;
021
022 /**
023 * Utility methods related to maps.
024 *
025 * @author Yvonne Wang
026 * @author Alex Ruiz
027 */
028 public class Maps {
029
030 /**
031 * Returns {@code true} if the given map is {@code null} or empty.
032 * @param map the map to check.
033 * @return {@code true} if the given map is {@code null} or empty, otherwise {@code false}.
034 */
035 public static boolean isEmpty(Map<?, ?> map) {
036 return map == null || map.isEmpty();
037 }
038
039 /**
040 * Returns the {@code String} representation of the given map, or {@code null} if the given map is {@code null}.
041 * @param map the map to format.
042 * @return the {@code String} representation of the given map.
043 */
044 public static String format(Map<?, ?> map) {
045 if (map == null) return null;
046 Iterator<?> i = map.entrySet().iterator();
047 if (!i.hasNext()) return "{}";
048 StringBuilder b = new StringBuilder();
049 b.append("{");
050 for (;;) {
051 Entry<?, ?> e = (Entry<?, ?>) i.next();
052 b.append(format(map, e.getKey()));
053 b.append('=');
054 b.append(format(map, e.getValue()));
055 if (!i.hasNext()) return b.append("}").toString();
056 b.append(", ");
057 }
058 }
059
060 private static Object format(Map<?, ?> map, Object o) {
061 return o == map ? "(this Map)" : toStringOf(o);
062 }
063
064 private Maps() {}
065 }