简化抽象 class 的多重继承 classes（内容相同）

Question

我喜欢在我的应用程序中计算多项内容并将值保存到 android sharedpreferences。一切正常，但总体上我对 class 设计不满意。

非常简单的抽象class。 Class 参数用于命名 sharedPreferences 中的键。

public abstract class Counter {

    private Context mContext;
    private Class mClass;

    Counter(Class myClass, Context context) {
        this.mClass = myClass;
        this.mContext = context;
    }

    public Integer getValue() {
        return PrefManager.with(mContext).getInt(mClass.getName(), 0);
        //return UniversalPreferences.getInstance().get(counterName, 1);
    }

    public void increment() {
        PrefManager.with(mContext).save(mClass.getName(), getValue() + 1);
        //UniversalPreferences.getInstance().put(counterName, getCurrentValue(counterName) + 1);
    }
}

到目前为止，我已经有 5 个 class 继承自 Counter，内容完全相同。

public class CounterAppLaunch extends Counter {

    @SuppressLint("StaticFieldLeak")
    private static CounterAppLaunch instance;

    private CounterAppLaunch(Context context) {
        super(CounterAppLaunch.class, context);
    }

    public static CounterAppLaunch getInstance(Context context) {
        if(CounterAppLaunch.instance == null) {
            CounterAppLaunch.instance = new CounterAppLaunch(context);
        }
        return CounterAppLaunch.instance;
    }
}

我有一些计数器，我喜欢从不同的 classes 调用并在那里递增（例如 CounterAPICall 或 CounterOnResumeCallExample）。这适用于这段代码。

Answer 1

借助依赖注入和HasA，我们可以试试，

public class CounterAppLaunch{
    @Autowired
    CounterAdapter counterAdapter;
    @SuppressLint("StaticFieldLeak")
    private static CounterAppLaunch instance;

    private CounterAppLaunch(Context context) {
        super(CounterAppLaunch.class, context);
    }

    public static CounterAppLaunch getInstance(Context context) {
        if(CounterAppLaunch.instance == null) {
            CounterAppLaunch.instance = new CounterAppLaunch(context);
        }
        return CounterAppLaunch.instance;
    }
}

CounterAdapter extends Counter{
    @Autowired
    private Context mContext;
    @Autowired
    private Class mClass;
    // getter and setter
}

public abstract class Counter {


    private Context mContext;

    private Class mClass;

    Counter(Class myClass, Context context) {
        this.mClass = myClass;
        this.mContext = context;
    }

    public Integer getValue() {
        return PrefManager.with(mContext).getInt(mClass.getName(), 0);
        //return UniversalPreferences.getInstance().get(counterName, 1);
    }

    public void increment() {
        PrefManager.with(mContext).save(mClass.getName(), getValue() + 1);
        //UniversalPreferences.getInstance().put(counterName, getCurrentValue(counterName) + 1);
    }
}

Answer 2

此代码可能有助于检索适当的计数器：

public Counter{
    private int count;

    public Counter(){
        count = 0;
    }

    public int getValue(){
        return count;
    }

    public void increment(){
        counter++;
    }
}

public CounterStorage(){
    private static HashMap<String, Counter> counterMap = new HashMap<>();

    public static Counter getInstance(String str){
        if (counterMap.containsKey(str)) return counterMap.get(str);

        Counter newCounter = new Counter();
        counterMap.add(str, newCounter);
        return newCounter;

    }
}

在这种情况下，Counter 不是抽象的 class。无论出于何种目的，您都可以为计数器命名，该名称存储在地图中。

简化抽象 class 的多重继承 classes（内容相同）

Simplify multiple inheriting classes (with all same content) of abstract class

java

inheritance

abstract-class