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 the original author or authors. 014 */ 015 package org.fest.util; 016 017 import static org.fest.util.Strings.quote; 018 019 import java.util.Iterator; 020 import java.util.Map; 021 import java.util.Map.Entry; 022 023 /** 024 * Understands utility methods related to maps. 025 * 026 * @author Yvonne Wang 027 * @author Alex Ruiz 028 */ 029 public class Maps { 030 031 /** 032 * Returns <code>true</code> if the given map is <code>null</code> or empty. 033 * @param map the map to check. 034 * @return <code>true</code> if the given map is <code>null</code> or empty, otherwise <code>false</code>. 035 */ 036 public static boolean isEmpty(Map<?, ?> map) { 037 return map == null || map.isEmpty(); 038 } 039 040 /** 041 * Returns the <code>String</code> representation of the given map, or <code>null</code> if the given map is 042 * <code>null</code>. 043 * @param map the map to format. 044 * @return the <code>String</code> representation of the given map. 045 */ 046 public static String format(Map<?, ?> map) { 047 if (map == null) return null; 048 Iterator<?> i = map.entrySet().iterator(); 049 if (!i.hasNext()) return "{}"; 050 StringBuilder b = new StringBuilder(); 051 b.append("{"); 052 for (;;) { 053 Entry<?, ?> e = (Entry<?, ?>)i.next(); 054 b.append(format(map, e.getKey())); 055 b.append('='); 056 b.append(format(map, e.getValue())); 057 if (!i.hasNext()) return b.append("}").toString(); 058 b.append(", "); 059 } 060 } 061 062 private static Object format(Map<?, ?> map, Object o) { 063 return o == map ? "(this Map)" : quote(o); 064 } 065 066 private Maps() {} 067 }