如何分别减少列表的数量如何多次使用列表

Question

我有问题，以简化我的代码与许多地图和列表。

public List<Map<String, Object>> getResultFromExcelFile() throws Exception {
    ArrayList<Map<String, Object>> allResults = new ArrayList<>();


    Map<String, Object> previousYearResult = new HashMap<>();
    Map<String, Object> actYearResult = new HashMap<>();
    Map<String, Object> plusOneYearResult = new HashMap<>();
    Map<String, Object> plusTwoYearResult = new HashMap<>();


    ArrayList<Map<String, Object>> previousYearResultActList = new ArrayList<>();

    ArrayList<Map<String, Object>> actYearResultPlanList = new ArrayList<>();
    ArrayList<Map<String, Object>> actYearResultFcList = new ArrayList<>();
    ArrayList<Map<String, Object>> actYearResultActList = new ArrayList<>();

    ArrayList<Map<String, Object>> plusOneYearResultPlanList = new ArrayList<>();
    ArrayList<Map<String, Object>> plusOneYearResultFcList = new ArrayList<>();
    ArrayList<Map<String, Object>> plusOneYearResultActList = new ArrayList<>();

    ArrayList<Map<String, Object>> plusTwoYearResultPlanList = new ArrayList<>();
    ArrayList<Map<String, Object>> plusTwoYearResultFcList = new ArrayList<>();
    ArrayList<Map<String, Object>> plusTwoYearResultActList = new ArrayList<>();

    for (int i = 20; i < 67; i++) {
        for (int j = 526; j < 1141; j++) {
            if (i < BEGIN_COLUMN_YEAR_MINUS_1 + 12) {
                //act
                if (findFirstDigit(getWorkBook().getNumber(j, 1)) == 1) {
                    previousYearResultActList.add(this.buildResultMap(i, j));
                }
            }
            if (i >= BEGIN_COLUMN_YEAR_0 && i < BEGIN_COLUMN_YEAR_0 + 12) {
                //plan
                if (findFirstDigit(getWorkBook().getNumber(j, 1)) == 3) {
                    actYearResultPlanList.add(this.buildResultMap(i, j));
                }
                //fc
                if (findFirstDigit(getWorkBook().getNumber(j, 1)) == 2) {
                    actYearResultFcList.add(this.buildResultMap(i, j));
                }
                //act
                if (findFirstDigit(getWorkBook().getNumber(j, 1)) == 1) {
                    actYearResultActList.add(this.buildResultMap(i, j));
                }
            }

            if (i >= BEGIN_COLUMN_YEAR_1 && i < BEGIN_COLUMN_YEAR_1 + 12) {
                if (findFirstDigit(getWorkBook().getNumber(j, 1)) == 3) {
                    //plan
                    plusOneYearResultPlanList.add(this.buildResultMap(i, j));
                }
                if (findFirstDigit(getWorkBook().getNumber(j, 1)) == 2) {
                    //fc
                    plusOneYearResultFcList.add(this.buildResultMap(i, j));
                }
                if (findFirstDigit(getWorkBook().getNumber(j, 1)) == 1) {
                    //act
                    plusOneYearResultActList.add(this.buildResultMap(i, j));
                }
            }
            if (i >= BEGIN_COLUMN_YEAR_2 && i < BEGIN_COLUMN_YEAR_2 + 12) {
                if (findFirstDigit(getWorkBook().getNumber(j, 1)) == 3) {
                    //plan
                    plusTwoYearResultPlanList.add(this.buildResultMap(i, j));
                }
                if (findFirstDigit(getWorkBook().getNumber(j, 1)) == 2) {
                    //fc
                    plusTwoYearResultFcList.add(this.buildResultMap(i, j));
                }
                if (findFirstDigit(getWorkBook().getNumber(j, 1)) == 1) {
                    //act
                    plusTwoYearResultActList.add(this.buildResultMap(i, j));
                }
            }
        }
    }
    previousYearResult.put("actList", previousYearResultActList);

    actYearResult.put("planList", actYearResultPlanList);
    actYearResult.put("fcList", actYearResultFcList);
    actYearResult.put("actList", actYearResultActList);

    plusOneYearResult.put("planList", plusOneYearResultPlanList);
    plusOneYearResult.put("fcList", plusOneYearResultFcList);
    plusOneYearResult.put("actList", plusOneYearResultActList);

    plusTwoYearResult.put("planList", plusTwoYearResultPlanList);
    plusTwoYearResult.put("fcList", plusTwoYearResultFcList);
    plusTwoYearResult.put("actList", plusTwoYearResultActList);


    allResults.add(previousYearResult);
    allResults.add(actYearResult);
    allResults.add(plusOneYearResult);
    allResults.add(plusTwoYearResult);

    return allResults;
}

 if (i >= BEGIN_COLUMN_YEAR_0 && i < BEGIN_COLUMN_YEAR_0 + 12) {...}

我想填充3个列表，然后填充到匹配的地图。清空3个列表，并在下一个if条件中再次填充它们，然后将它们传递到匹配映射中。

有人知道我如何最好地实现这一点，从而减少列表的数量吗？谢谢你

Answer 1

似乎三种类型的代码非常相似。您应该创建一个可重用的函数

public ArrayList<Map<String, Object>> readExcel(int beginColumnYear) {
ArrayList<Map<String, Object>> list = new ArrayList<>();
for (int i = 20; i < 67; i++) {
    for (int j = 526; j < 1141; j++) {
        if (i >= beginColumnYear && i < beginColumnYear + 12) {
                if (findFirstDigit(getWorkBook().getNumber(j, 1)) == 3) {
                    list.add(this.buildResultMap(i, j));
                }
                ...
            }
    }     
}
return list;
}

...
actYearResult.put("planList", readExcel(BEGIN_COLUMN_YEAR_0));
...

此外，还应该优化代码的速度和内存使用