根据key或value将map容器进行排序

java中的HashMap是无序的，有序容器可用LinkedHashMap
在cmopare接口中，Integer或者Date通过compareTo方法进行对象比较时，“比较对象” 比 “被比较对象” 大时返回-1，相等时返回0，小则返回1。

public class ContainerHelper {/*** 将容器按照日期、数字等类型的键，排序** @param map* @param orderRule 0为升序，1为降序* @param keyType   0为数字类型  1为日期类型  2为时间格式的字符串* @return*/public static Map containerSortByKey(Map map, Integer keyType, Integer orderRule) {if (ConstantHelper.NUMBER_0 == keyType) {List<Map.Entry<Integer, Object>> keyList = new ArrayList<Map.Entry<Integer, Object>>(map.entrySet());Collections.sort(keyList, new Comparator<Map.Entry<Integer, Object>>() {@Overridepublic int compare(Map.Entry<Integer, Object> o1, Map.Entry<Integer, Object> o2) {return ConstantHelper.NUMBER_0 == orderRule ? o1.getKey().compareTo(o2.getKey()) : o2.getKey().compareTo(o1.getKey());}});HashMap<Integer, Object> resultMap = new LinkedHashMap<>();for (Map.Entry<Integer, Object> entry : keyList) {resultMap.put(entry.getKey(), entry.getValue());}return resultMap;} else if (ConstantHelper.NUMBER_1 == keyType) {List<Map.Entry<Date, Object>> keyList = new ArrayList<Map.Entry<Date, Object>>(map.entrySet());Collections.sort(keyList, new Comparator<Map.Entry<Date, Object>>() {@Overridepublic int compare(Map.Entry<Date, Object> o1, Map.Entry<Date, Object> o2) {return ConstantHelper.NUMBER_0 == orderRule ? o1.getKey().compareTo(o2.getKey()) : o2.getKey().compareTo(o1.getKey());}});HashMap<Date, Object> resultMap = new LinkedHashMap<>();for (Map.Entry<Date, Object> entry : keyList) {resultMap.put(entry.getKey(), entry.getValue());}return resultMap;} else if (ConstantHelper.NUMBER_2 == keyType) {List<Map.Entry<String, Object>> keyList = new ArrayList<Map.Entry<String, Object>>(map.entrySet());Collections.sort(keyList, new Comparator<Map.Entry<String, Object>>() {@Overridepublic int compare(Map.Entry<String, Object> o1, Map.Entry<String, Object> o2) {String timeStamp01 = o1.getKey();String timeStamp02 = o2.getKey();return ConstantHelper.NUMBER_0 == orderRule ? DateHelper.getDateByStr(timeStamp01, DateHelper.DATE_PATTERN_03).compareTo(DateHelper.getDateByStr(timeStamp02, DateHelper.DATE_PATTERN_03)): DateHelper.getDateByStr(timeStamp02, DateHelper.DATE_PATTERN_03).compareTo(DateHelper.getDateByStr(timeStamp01, DateHelper.DATE_PATTERN_03));}});HashMap<String, Object> resultMap = new LinkedHashMap<>();for (Map.Entry<String, Object> entry : keyList) {resultMap.put(entry.getKey(), entry.getValue());}return resultMap;}return null;}/*** 将容器按照日期、数字等类型的值，排序** @param map* @param valueType 0为数字类型  1为日期类型* @param orderRule 0为升序，1为降序* @return*/public static Map containerSortByValue(Map map, Integer valueType, Integer orderRule) {if (ConstantHelper.NUMBER_0 == valueType) {List<Map.Entry<Object, Integer>> valueList = new LinkedList<Map.Entry<Object, Integer>>(map.entrySet());Collections.sort(valueList, new Comparator<Map.Entry<Object, Integer>>() {@Overridepublic int compare(Map.Entry<Object, Integer> o1, Map.Entry<Object, Integer> o2) {return ConstantHelper.NUMBER_0 == orderRule ? o1.getValue().compareTo(o2.getValue()) : o2.getValue().compareTo(o1.getValue());}});HashMap<Object, Integer> resultMap = new LinkedHashMap<>();for (Map.Entry<Object, Integer> entry : valueList) {resultMap.put(entry.getKey(), entry.getValue());}return resultMap;} else if (ConstantHelper.NUMBER_1 == valueType) {List<Map.Entry<Object, Date>> valueList = new LinkedList<Map.Entry<Object, Date>>(map.entrySet());Collections.sort(valueList, new Comparator<Map.Entry<Object, Date>>() {@Overridepublic int compare(Map.Entry<Object, Date> o1, Map.Entry<Object, Date> o2) {return ConstantHelper.NUMBER_0 == orderRule ? (o1.getValue().compareTo(o2.getValue())) : (o2.getValue().compareTo(o1.getValue()));}});HashMap<Object, Date> resultMap = new LinkedHashMap<>();for (Map.Entry<Object, Date> entry : valueList) {resultMap.put(entry.getKey(), entry.getValue());}return resultMap;} else if (ConstantHelper.NUMBER_2 == valueType) {List<Map.Entry<Object, String>> keyList = new ArrayList<Map.Entry<Object, String>>(map.entrySet());Collections.sort(keyList, new Comparator<Map.Entry<Object, String>>() {@Overridepublic int compare(Map.Entry<Object, String> o1, Map.Entry<Object, String> o2) {String timeStamp01 = o1.getValue();String timeStamp02 = o2.getValue();return ConstantHelper.NUMBER_0 == orderRule ? DateHelper.getDateByStr(timeStamp01, DateHelper.DATE_PATTERN_03).compareTo(DateHelper.getDateByStr(timeStamp02, DateHelper.DATE_PATTERN_03)): DateHelper.getDateByStr(timeStamp02, DateHelper.DATE_PATTERN_03).compareTo(DateHelper.getDateByStr(timeStamp01, DateHelper.DATE_PATTERN_03));}});HashMap<Object, String> resultMap = new LinkedHashMap<>();for (Map.Entry<Object, String> entry : keyList) {resultMap.put(entry.getKey(), entry.getValue());}return resultMap;}return null;}
}

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根据key或value将map容器进行排序

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