Code Bad Smell 

 

Bad Code Smell 

來自重構這本書

散發異味的程式碼並不會立刻的造成功能上的損壞，但會造成系統的慢性病。

重覆的程式碼 - Duplicated Code

太長的函式 - Long Method

Example

DiningApplyBOImpl - queryOrderSummary

過大的類別 - Large Class

DiningBOImpl.java

DiningBOImpl.java

過長的參數列

 Long Parameter List

Example

  • 通常比較少發生這種狀況，大部分都被 JsonString 包住了。

// 寫法一
public String queryBiweeklyBellSetting(String jsonString) throws Exception {		
    JSONObject bellObj=JSONObject.fromObject(jsonString); 

    Personal person=settingFeeEBO.queryPersonalByEmpid(bellObj.getString("empid"));	
    	
    List<SettingFeeSummary> SettingFeeSummaryList = 
            this.querySettingBellByPeriod(person, 
                        bellObj.getString("startDate"),bellObj.getString("endDate"));
		
    return CommonUtils.getBeansJson(SettingFeeSummaryList, SettingFeeSummaryList.size());
}

SettingFeeBOImpl.java


// 寫法二
public List<SettingFeeSummary> queryBiweeklyBellSetting(String empId, 
                                       String startDate, String endDate) throws Exception {		

    Personal person=settingFeeEBO.queryPersonalByEmpid(empId);	
    	
    List<SettingFeeSummary> SettingFeeSummaryList = 
                    this.querySettingBellByPeriod(person, startDate, endDate);
		
    return SettingFeeSummaryList;
}
SettingFeeBOImpl.java

發散式變化

Divergent Chnage

  • 多個變動會改在同一支檔案或是 Class

霰彈式修改

Shotgun Surgery

  • 一個變動改多個地方


if (ouLocation == "TW")
    $("#source").html(sourceContent);
else
    $("#source").html(sourceContentS1);

資料泥團

Data Clumps

  • 總是綁在一起出現的資料

Transfer getTransfer(String empid, String sDate, String eDate) throws Exception;

List<Mealfee> queryMealfeeByStartEnd(String empid, String startDate, String endDate) throws Exception;

Integer queryMealFeeType(String empid, String startDate, String endDate) throws Exception;

List<Transfer> getTransfer_new(String applicant ,String sDate, String eDate) throws Exception;

List<BtripView> getBtripByWorkingDate(String empid, String startDate,
                                      String endDate,String lampStart) throws Exception;
String queryShiftType(String empid, String date) throws Exception;

String queryGuardShiftType(String empid, String date) throws Exception;

List<DayOfMealfee> queryDayOfMealfeeByWorkingDate (String empid,String workingDate) throws Exception ;

Double getOvertimeShift(String empid,String workDate) throws Exception;
    
Double getGuardShift(String empid,String workDate) throws Exception;

基本型別偏執

Primitive Obession

  • 勇敢的建立小型 Class

String startDate,String endDate
class Period

注釋

Comments

Gin 式注解

常常被註解掉的 Transactional

名人堂式註解

結論

  • 來試試 IDE 提供的 Refactor 功能吧 !
    • Extract Method..
    • Extract Constants...
    • Rename variable and method..
  • 記得 Java 是一門 Compile Language

有些事就像路上

看到垃圾

不撿也不會死

但撿了會比較愛地球

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