1,從hbase中讀出數(shù)據(jù)并存儲在ArrayList<Map<String,String>>中，

@Overridepublic ArrayList<Map<String, Object>> getAllHistoryOrderByTime(String namespace, String tableName) {TableName tablename=TableName.valueOf(FillDataTableName(namespace,tableName));Table table = null;ArrayList<Map<String,Object>> arrayList = new ArrayList<>();try {conn = ConnectionFactory.createConnection(conf);//管理類table = conn.getTable(tablename);ResultScanner results = table.getScanner(new Scan());for (Result result : results){Map<String,Object> map = new HashMap<>();for(Cell cell : result.rawCells()){String row = Bytes.toString(cell.getRowArray(), cell.getRowOffset(), cell.getRowLength());//String family =? Bytes.toString(cell.getFamilyArray(),cell.getFamilyOffset(),cell.getFamilyLength());String colName = Bytes.toString(cell.getQualifierArray(),cell.getQualifierOffset(),cell.getQualifierLength());String value = Bytes.toString(cell.getValueArray(), cell.getValueOffset(), cell.getValueLength());map.put("modelName",row);if(colName.equals("tableName")){map.put("tableName",value);}if(colName.equals("project")){map.put("project",value);}if(colName.equals("columns")){ArrayList<String> columnsList = StringOptions.String2ArrayList(value);map.put("columns",columnsList);}if(colName.equals("preProcess")){ArrayList<String> preProcessList = StringOptions.String2ArrayList(value);map.put("preProcess",preProcessList);}if(colName.equals("result")){map.put("result",value);}if(colName.equals("params")){Map<String,String> paramsMap = StringOptions.String2Map(value);map.put("params",paramsMap);}//獲取時間戳long lTmstmp = cell.getTimestamp();Date date = new Date(lTmstmp);map.put("Date",date.toString());}arrayList.add(map);}} catch (IOException e) {e.printStackTrace();}return SortOptions.sortByTime(arrayList);} 其中ArrayList<Map<String,String>>初始化為： ArrayList<Map<String,String>> arrayList = new ArrayList<>(); arrayList.add(new HashMap<String, String>() {{put("Name","1");put("Date","Sat Sep 21 16:06:55 CST 2019"); } });

2、將ArrayList<Map<String,String>>按照時間戳進行排序

public static ArrayList<Map<String,String>> sortByTime(ArrayList<Map<String,String>> inputArrayList){Comparator c = new Comparator<Map<String,String>>() {@Overridepublic int compare(Map<String,String> o1, Map<String,String> o2) {// TODO Auto-generated method stubif(string2Date(o1.get("Date")).before(string2Date(o2.get("Date"))))return 1;//注意！！返回值必須是一對相反數(shù)，否則無效。jdk1.7以后就是這樣。//??? else return 0; //無效else return -1;}};Collections.sort(inputArrayList,c);return inputArrayList; }

3、將字符串轉(zhuǎn)換為Date類型

public static Date string2Date(String strDate) {Date date = new Date();SimpleDateFormat sdf = new SimpleDateFormat("EEE MMM dd HH:mm:ss z yyyy", java.util.Locale.US);try {date = sdf.parse(strDate.toString());} catch (ParseException e) {e.printStackTrace();}return date;}

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