Java類使用未經檢查或不安全的操作

Question

我有一個名爲LB_Adapter.java的類來幫助在ListView中顯示我的數據庫。我的計劃做工精細的所有功能，但我仍然得到一個警告錯誤每次我編譯的時候，說

Note: Project/LB_Adapter.java uses unchecked or unsafe operations. 
Note: Recompile with -Xlint:unchecked for details. 

從谷歌上搜索我理解錯誤來自我的ArrayList，但我試過實現的ArrayList（），它沒有按沒有工作。有沒有辦法擺脫錯誤，或者它甚至不重要，因爲它不影響任何東西？

相關代碼：

public class LB_Adapter extends ArrayAdapter<Object> { 
List<Object> list = new ArrayList<>(); 

public LB_Adapter(Context context, int resource){ 
    super(context, resource); 
} 

public void add(LB object){ 
    list.add(object); 
    super.add(object); 
} 

@Override 
public int getCount(){ 
    return list.size(); 
} 

@Override 
public Object getItem(int position){ 
    return list.get(position); 
} 

@Override 
public View getView(int position, View convertView, ViewGroup parent) { 
    View row = convertView; 
    LBHolder lbholder; 

    if(row==null){ 
     LayoutInflater layoutinflater = (LayoutInflater) this.getContext().getSystemService(getContext().LAYOUT_INFLATER_SERVICE); 
     row = layoutinflater.inflate(R.layout.display_leaderboard_row, parent, false); 
     lbholder = new LBHolder(); 
     lbholder.lb_rank = (TextView) row.findViewById(R.id.lb_rank); 
     lbholder.lb_score = (TextView) row.findViewById(R.id.lb_score); 
     lbholder.lb_time = (TextView) row.findViewById(R.id.lb_time); 
     row.setTag(lbholder); 
    } 
    else { 
     lbholder = (LBHolder) row.getTag(); 
    } 
    LB leaderboard = (LB) getItem(position); 
    lbholder.lb_rank.setText(leaderboard.getRank().toString()); 
    lbholder.lb_score.setText(Integer.toString(leaderboard.getScore())); 
    lbholder.lb_time.setText(leaderboard.getTime().toString()); 

    return row; 
} 

static class LBHolder{ 
    TextView lb_rank, lb_score, lb_time; 
} 
} 

Answer 1

使用原始類型已經氣餒，因爲泛型是在Java 5中引入了你應該只需要輸入參數的ArrayAdapter和ArrayList您同時使用：

public class LB_Adapter extends ArrayAdapter<LB> { 
    // Here --------------------------------^ 

    // And here: 
    List<LB> list = new ArrayList<>(); 

    public LB_Adapter(Context context, int resource){ 
     super(context, resource); 
    } 

    public void add(LB object){ 
     list.add(object); 
     super.add(object); 
    } 
}