如何通过剪切重复代码来优化程序

Question

在我的程序代码中，我总是使用以下构造，但它非常重复。你能告诉我如何优化吗？谢谢

switch(PublicPar.StoredNumberTypeForUI){
  case NumberOfReceiver:
    break;
  case NumberOfOnly:
    break;
  case NumberOfExcept:
      finish(); 
    break;
}

我的程序代码

public class StepList extends ListActivity{
    private ListNumberAdapter mListNumberAdapter=null;
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.sms_step_list); 
        SetTitle();
        IniControl();   
        IniListView();      
    }
    protected void onActivityResult(int requestCode, int resultCode, Intent data) {
        switch (requestCode) {
        case 50:
            if (resultCode == RESULT_OK) {
                List<String> s=null;
                switch(PublicPar.StoredNumberTypeForUI){
                  case NumberOfReceiver:
                      s=PublicPar.SharedRule.receiverNumberList;     
                    break;
                  case NumberOfOnly:
                      s=PublicPar.SharedRule.onlyNumberList;    
                    break;
                  case NumberOfExcept:
                      s=PublicPar.SharedRule.exceptNumberList;  
                    break;
                }                                   
            }
            break;
        default:
            break;
        }
    }   
    private void SetTitle(){
        TextView tvTitle=((TextView)findViewById(R.id.tvTitle));
        switch(PublicPar.StoredNumberTypeForUI){
          case NumberOfReceiver:
              tvTitle.setText(getString(R.string.TitleOfReceiverNumber));
            break;
          case NumberOfOnly:
              tvTitle.setText(getString(R.string.TitleOfOnlyNumber));
            break;
          case NumberOfExcept:
              tvTitle.setText(getString(R.string.TitleOfExceptNumber));
            break;
        }
    }

    private void AddTelNumber(){
        switch(PublicPar.StoredNumberTypeForUI){
          case NumberOfReceiver:
              PublicPar.SharedRule.receiverNumberList.add(" ");  
            break;
          case NumberOfOnly:
              PublicPar.SharedRule.onlyNumberList.add(" "); 
            break;
          case NumberOfExcept:
              PublicPar.SharedRule.exceptNumberList.add(" ");   
            break;
        }   
        mListNumberAdapter.notifyDataSetChanged();
    }

    private void FillListView(){
        switch(PublicPar.StoredNumberTypeForUI){
          case NumberOfReceiver:
              if (PublicPar.SharedRule.receiverNumberList.size()<1){
                  PublicPar.SharedRule.receiverNumberList.add(" ");
                  mListNumberAdapter=new ListNumberAdapter(this,PublicPar.SharedRule.receiverNumberList);
              }
            break;
          case NumberOfOnly:
              if (PublicPar.SharedRule.onlyNumberList.size()<1){
                  PublicPar.SharedRule.onlyNumberList.add(" ");
                  mListNumberAdapter=new ListNumberAdapter(this,PublicPar.SharedRule.onlyNumberList);
              }           
            break;
          case NumberOfExcept:
              if (PublicPar.SharedRule.exceptNumberList.size()<1){
                  PublicPar.SharedRule.exceptNumberList.add(" ");
                  mListNumberAdapter=new ListNumberAdapter(this,PublicPar.SharedRule.exceptNumberList);
              }               
            break;
        }           
    }
    private void HandleNext(){
        switch(PublicPar.StoredNumberTypeForUI){
          case NumberOfReceiver:
                Intent intent = new Intent().setClass(getApplicationContext(),ui.StepOption.class);
                startActivity(intent);
                finish();
            break;
          case NumberOfOnly:
             finish();
            break;
          case NumberOfExcept:
              finish(); 
            break;
        }               
    }

    private void HanleBack(){
        switch(PublicPar.StoredNumberTypeForUI){
          case NumberOfReceiver:            
                Intent intent = new Intent().setClass(getApplicationContext(),ui.StepName.class);
                startActivity(intent);
                finish();
            break;
          case NumberOfOnly:
              Intent intent1 = new Intent().setClass(getApplicationContext(),ui.StepOption.class);
              startActivity(intent1);
              finish();
            break;
          case NumberOfExcept:
              Intent intent2 = new Intent().setClass(getApplicationContext(),ui.StepOption.class);
              startActivity(intent2);
              finish(); 
            break;
        }       
    }

    private void IniControl(){  
        findViewById(R.id.btnBack).setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {
                HanleBack();
            }
        }); 
        findViewById(R.id.btnNext).setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {   
                HandleNext();
            }
        });
        findViewById(R.id.btnCancel).setOnClickListener(new OnClickListener() {
            @Override
            public void onClick(View v) {               
                finish();
            }
        });             
    }

}

Answer 1

原则上，枚举可能有方法。

enum MyEnum {
    FIRST{String xyz(){return "x";}}, SECOND{String xyz(){return "y";}}, THIRD{String xyz(){return "z";}};
    abstract String xyz();
}
public class A {
    public static void main(String[] p) {
        for (MyEnum m : MyEnum.values()) {
            System.out.println(" "+m+" ==> "+m.xyz());
        }
    }
}

而不是写

void doThis() {
    switch(x) {
    case FIRST: doX(); break;
    case SECOND: doY(); break;
    case THIRD: doZ(); break;
    }
}

你可以写

void doThis() { x.doThis(MyActivity.this); } // or whatever data you really need there

前提是在每个枚举值中定义doThis(MyActivity a)。但这不会使代码变得更短，它将提供不同的观点。

如果你只是想让代码看起来更短，像我在这里做的那样删除不必要的换行符。（我必须注意的是，在实践中，人们更倾向于用工具重新格式化代码，然后指责它不可读，而不是认为异常格式化背后可能有原因。）