java - 将方法的复杂度降低 14

Question

Pmd 告诉我这个方法 (thirdRowsValidation) 的复杂度为 14，但我无法找到减少代码的模式。

indexBookngEnd、indexTravelStart ...所有这些变量都是在另一个循环迭代中创建的其他数组的索引(csv 文件列的标题)- Ref1

public void thirdRowsValidation(String thirdRowCsv) {
        String[] lines1 = thirdRowCsv.split(",");
        for (int i = 0; i < lines1.length; i++) {

            if (indexBookngEnd == i && "".equals(temporalValidateBookngEnd)) {
                temporalValidateBookngEnd = (" to " + lines1[i] + "\n");

            }
            if (indexBookngStart == i
                    && !("".equals(temporalValidateBookngEnd))) {
                finalOutput.append("Then it should have booking window ");

                indexBookngStart = -1;

            }

            if (indexTravelEnd == i && "".equals(temporalValidateTravelEnd)) {
                temporalValidateTravelEnd = (" to " + lines1[i] + "\n");

            }

            if (indexTravelStart == i
                    && !("".equals(temporalValidateTravelEnd))) {

                finalOutput.append("Then it should have travel window ");

                String idHeaderColumn = String.format("%1$-" + 5 + "s", "id");
                String typeHEaderColumn = String.format("%1$-" + 50 + "s","type");
                finalOutput.append("| ");
                finalOutput.append(idHeaderColumn);

                indexTravelStart = -1;
            }

            if (indexPackageDescription == i) {
                temporalPackages = String.format("%1$-" + 50 + "s", lines1[i]);

            }

            if (indexPackageCode == i
                    && !(lines1[i].matches("[+-]?\\d*(\\.\\d+)?"))
                    && indexTravelStart == -1) {

                finalOutput.append("| ");


            }

        }

    }

引用 1:

public void secondRowValidation(String secondRowCsv) {

        String[] lines1 = secondRowCsv.split(",");
        for (int i = 0; i < lines1.length; i++) {

            if ("Bookng start".equalsIgnoreCase(lines1[i])) {
                indexBookngStart = i;
            }
            if ("Bookng end".equalsIgnoreCase(lines1[i])) {
                indexBookngEnd = i;
            }

从\n 到 ","的数组

public String getStoryFromCsv(String convert) {
        String[] lines = convert.split("(\n)");
        for (int j = 0; j < lines.length; j++) {

            arrayPerRow = lines[j];
            if (j == 0) { // get marketing type and number
                firstRowValidation(arrayPerRow);
            }
            if (j == 1) { // get headers
                secondRowValidation(arrayPerRow);
            }
            if (j > 1) { // get info and append according to headers
                thirdRowsValidation(arrayPerRow);
            }

        }

所以我有: - 方法 thirdRowsValidation() 的 NPath 复杂度为 649 - 方法“thirdRowsValidation”的圈复杂度为 14。

最后我写了这样一段文字，只是为了你们有一个想法:

Then it should have booking window 8/8/16 to 10/8/16
Then it should have travel window 11/6/16 to 12/25/16
And it should have online packages:
| id    | type                                              |
| 34534 | aaa Pkg                                           |
| D434E | MKW Pkg + asdasdasdasdasdasdas                    |
| F382K | sds Pkg + Ddding                                  |
| X582F | OYL Pkg + Deluxe Dining                           |

Answer 1

该方法的复杂性很高，因为它要做很多不同的事情。尝试每种方法做一件事。

public String getStoryFromCsv(String csv) {
    StringBuilder story = new StringBuilder();
    String[] lines = csv.split("\n”);
    appendBookingWindowValidation(story, lines[0]);
    appendTravelWindowValidation(story, lines[1]);
    appendOnlinePackageValidation(story, lines);
    return story.toString();
}

private void appendBookingWindowValidation(StringBuilder story, String firstLine) {
    story.append("Then it should have booking window ");
    // extract start and end date from 'firstLine'
    // and append them to the story
}

private void appendTravelWindowValidation(StringBuilder story, String secondLine) {
    story.append("Then it should have travel window ");
    // extract start and end date from 'secondLine'
    // and append them to the story
}

private void appendOnlinePackageValidation(StringBuilder story, String[] lines) {
    story.append("And it should have online packages:\n")
         .append("| id    | type                                              |\n");
    for (int i = 2 ; i < lines.length; i++) {
      // create and append a row of the online packages table
   }
}

尝试将方法所需的所有内容作为其参数之一传递。方法不应依赖于在不同方法中设置的字段的值。这样可以降低复杂性，并使代码更易于阅读、理解和测试。

如果一个方法或类具有很高的复杂性，那么通常意味着它试图同时做太多不同的事情。退后一步，尝试确定它所做的不同事情并分别实现它们。这将自动生成复杂度较低的代码。

将内部循环提取到新方法中通常是一种快速破解方法，有助于降低单个方法的复杂性，但不会降低整个类的复杂性。